Elroy Chester v. Rick Thaler, Director

REVISED JANUARY 3, 2012
IN THE UNITED STATES COURT OF APPEALS
FOR THE FIFTH CIRCUIT United States Court of Appeals
Fifth Circuit

FILED
December 30, 2011

No. 08-70023 Lyle W. Cayce
Clerk

ELROY CHESTER,

Petitioner - Appellant
v.

RICK THALER, DIRECTOR, TEXAS DEPARTMENT OF CRIMINAL
JUSTICE, CORRECTIONAL INSTITUTIONS DIVISION,

Respondent - Appellee

Appeal from the United States District Court
for the Eastern District of Texas

Before JONES, Chief Judge, and STEWART and DENNIS, Circuit Judges.
EDITH H. JONES, Chief Judge:
Petitioner Elroy Chester (“Petitioner”) confessed and pled guilty to capital
murder and was sentenced to death by a Texas jury. His conviction and
sentence were affirmed on direct appeal. He sought post-conviction relief from
the Texas courts, alleging that he is mentally retarded, and his execution will
therefore be unconstitutional. The Texas trial court and Court of Criminal
Appeals determined that Chester was not mentally retarded. Petitioner then
applied for a writ of habeas corpus via 28 U.S.C. § 2254. The federal district
court denied relief, and he now appeals. The state’s legal conclusions neither
contradicted nor unreasonably applied federal law, nor were its factual
 No. 08-70023

conclusions unreasonable in light of the evidence presented in the state
proceedings. See 28 U.S.C. § 2254(d)(1)-(2); Riddle v. Cockrell, 288 F.3d 713, 716
(5th Cir. 2002). We therefore AFFIRM.
BACKGROUND
In 1997 and 1998, Petitioner embarked on a criminal spree too long and
too gruesome to recount here in its full detail. He perpetrated at least five
burglaries and five non-lethal assaults; worse, he left in his wake the victims,
ranging from ten to eighty-seven years old, of at least five murders and three
rapes. Petitioner’s career as a serial murderer and rapist culminated in the
events of February 6, 1998, when his final victim, Willie Ryman III, discovered
Petitioner raping his nieces, and Petitioner shot and killed Ryman.
On that evening, Erin DeLeon was at home alone with her small child.
After cutting the telephone wires and tampering with the security light between
the garage and house, Petitioner entered the house through the unlocked
kitchen door, wearing a ski-mask and gloves. With a gun to the back of Erin’s
head and her ponytail in his hand, he led her from room to room to retrieve
valuables. He then brought her to the living room and ordered her to turn off
the lights and draw the blinds. When Claire DeLeon, Erin’s sister, returned to
the home with her boyfriend Tim, Petitioner demanded their money and jewelry,
then ordered them into the bathroom. Alone again with Erin, he forced her to
undress, then blindfolded her with duct tape. He then ordered Tim to return,
forced him to strip as well, and restrained him with duct tape. Finally he
ordered Claire to enter and strip and blindfolded her with duct tape. He raped
Erin and forced other sex acts, holding a gun against her head and threatening

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to “blow her head off” if she resisted. He repeated this threat when he forced
Claire to perform sex acts.
Willie Ryman III, the DeLeon sisters’ uncle, arrived at this scene with his
girlfriend Marcia Sharp, who stayed in the car while Ryman approached the
house. Petitioner went to the back door and murdered Ryman with a single
shot. He then approached the car, where he began shooting at its locked doors.
He fired two more shots into the car before fleeing the scene.
Chester was quickly implicated and captured. He confessed to Ryman’s
murder and led police to the murder weapon. Although he lied to the police
about where it was hidden, and about the fact that it was loaded, apparently
trying to mount a violent escape, he did not succeed. He also confessed to a host
of other horrific crimes. After pleading guilty to capital murder, he was
sentenced to death by a Texas jury. His conviction and sentence were affirmed
on direct appeal. Chester sought post-conviction relief at the state and federal
levels on the grounds that he could not be executed because he is mentally
retarded. Relying on the United States Supreme Court’s opinion in Atkins v.
Virginia, 536 U.S. 304 (2002) (holding that the execution of the mentally
retarded violates the Eighth Amendment), and on the factors set forth in Ex
Parte Briseno, 135 S.W.3d 1, 5 (Tex. Crim. App. 2004) (implementing Atkins), the
use of which our court has repeatedly blessed, the Texas trial court and Texas
Court of Criminal Appeals (“TCCA”) determined that Chester was not mentally
retarded. Ex parte Chester, 2007 WL 602607 (Tex. Cr. App. 2007) (unpublished)
(“Chester I”).
The TCCA’s detailed and thorough opinion concluded that Chester met two
of the three necessary requirements for a finding of m ental

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retardation–significant limitations in intellectual functioning and deficiencies
that appeared early in life–but that he did not show “significant deficits in
adaptive behavior.” Id. at *3-*4. It cited Briseno for the proposition “that courts
should use the definitions of mental retardation as stated by the American
Association of Mental Retardation” and for a suggested serious of questions
which would assist in determining the existence of deficits in adaptive behavior.
Id. at *1. It acknowledged that these suggested questions were “intended only
to be guidelines for the trial courts” to help them make the mental retardation
determination required by Atkins “until the Legislature was to . . . establish
conclusively both the substantive laws and the procedures that would bring our
codes into compliance with the mandate issued by Atkins.” Id. at *3. The
legislature had not intervened, however, and so the Briseno factors remained the
only legal guidance for lower Texas courts in applying the AARM definition and
determining the presence or absence of “significant deficits in adaptive
behavior.” Id.
The TCCA concluded that the trial court’s finding that Petitioner failed to
demonstrate significant deficits in adaptive behavior was supported by the
evidence. The trial court had heard Petitioner’s evidence regarding his 1987
“Vineland test,” on which he achieved a Vineland Adaptive Behavioral Scales
score (“VABS”) which would typically indicate mild mental retardation. It also,
however, heard evidence regarding Chester’s classification during his school
years as “learning disabled” (rather than retarded), and found more credible the
testimony of a diagnostician who testified that Petitioner’s school records were
accurate and that a “learning disability” designation does not imply mental
retardation. It also noted the planned nature of Petitioner’s crimes, both the

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capital crime and other crimes, in which Petitioner took a great many steps to
avoid detection. It noted that he acted independently rather than as an
accomplice. The trial court considered conflicting testimony regarding
Petitioner’s ability to converse coherently, and found more credible the testimony
of the expert who testified that Petitioner could converse coherently on a wide
range of topics. It found that Petitioner could lie and hide facts to protect
himself, as evidenced by his scheme to mislead investigators in order to obtain
his loaded gun while in custody. The TCCA therefore affirmed the trial court’s
factual finding that Petitioner failed to demonstrate significant deficits in
adaptive behavior by a preponderance of the evidence. Id. at *9.
Petitioner then applied for a writ of habeas corpus pursuant to
28 U.S.C. § 2254, now alleging (as he must) not only his own mental retardation
and the resulting unconstitutionality of his sentence, but that the TCCA’s
determination was contrary to and an unreasonable application of the holding
of Atkins, and that the TCCA’s decision was based on an unreasonable finding
of fact in light of the record before it. The federal district court denied relief, and
he appealed.
DISCUSSION
I. AEDPA Review
28 U.S.C. § 2254(d) bars relitigation of any claim “adjudicated on the
merits” in state court, subject only to exceptions in Section 2254(d)(1) and (d)(2).
Harrington v. Richter, 131 S. Ct. 770, 784 (2011). Section 2254(d)(1) contains
two overlapping but distinct exceptions: an “unreasonable application” prong and
a “contrary to” prong. See Terry Williams v. Taylor, 529 U.S. 362, 404,
120 S. Ct. 1495, 1519 (2000). Federal courts may not grant habeas relief

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pursuant to § 2254(d)(1) “unless the adjudication of the claim . . . resulted in a
decision that was contrary to, or involved an unreasonable application of, clearly
established Federal law, as determined by the Supreme Court of the United
States.” 28 U.S.C. § 2254(d)(1). In this context, “clearly established federal law
‘refers to the holdings, as opposed to the dicta, of [the Supreme] Court’s decisions
as of the time of the relevant state-court decision.’” Valdez v. Cockrell, 274 F.3d
941, 946 (5th Cir. 2001) (quoting Terry Williams, 529 U.S. at 412, 120 S. Ct. at
1523).
Section 2254(d)(2) excepts from the general bar on relief those cases in
which the adjudication of the claim “resulted in a decision that was based on an
unreasonable determination of the facts in light of the evidence presented in the
State court proceeding.” 28 U.S.C. § 2254(d)(2). A reviewing federal court
presumes that the state court’s factual findings are sound unless the petitioner
rebuts the “presumption of correctness by clear and convincing evidence.”
Miller-El v. Dretke, 545 U.S. 231, 240, 125 S. Ct. 2317, 2325 (2005); Maldonado
v. Thaler, 625 F.3d 229, 236 (5th Cir. 2010). This standard is demanding but not
insatiable; deference does not by definition preclude relief. Miller-El, 545 U.S.
at 240, 125 S. Ct. at 2325.
As the Supreme Court has recently reminded, “If [§ 2254(d)’s] standard is
difficult to meet, that is because it was meant to be. . . . It preserves authority
to issue the writ where there is no possibility fairminded jurists could disagree
that the state court’s decision conflicts with [the Supreme] Court’s precedent.
It goes no farther.” Harrington, 131 S. Ct. at 786 (emphasis added) (internal
quotation marks and citation omitted).

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Petitioner claims that he is entitled to relief under both 28 U.S.C.
§ 2254(d)(1) and 28 U.S.C. § 2254(d)(2); he asserts that the state court’s
adjudication resulted in a decision contrary to and involving an unreasonable
application of clearly established federal law and was based on an unreasonable
determination of the facts in light of the evidence presented in the State Court
proceeding. We address these claims in turn.
II. Section 2254(d)(1) Claims
A state court’s judgment falls within the “unreasonable application”
exception of § 2254(d)(1) if the state court correctly identifies the governing
legal principle from the Supreme Court’s decisions, but unreasonably applies it
to the facts of the particular case, Busby, 359 F.3d at 713, or where it ‘extends
a legal principle from [Supreme Court] precedent to a new context where it
should not apply or unreasonably refuses to extend that principle to a new
context where it should apply.’” LaCaze v. Warden of La. Corr. Inst. for Women,
645 F.3d 728, 734 (5th Cir. 2011) (quoting Terry Williams, 529 U.S. at 407, 413,
120 S. Ct. at 1520, 1523). A federal court cannot reverse the denial of habeas
relief simply by concluding that the state court decision applied clearly
established federal law erroneously; rather, the court must conclude that such
application was also unreasonable. See Horn, 508 F.3d at 313. In fact, “a
condition for obtaining habeas corpus from a federal court” is a showing “that the
state court’s ruling on the claim being presented . . . was so lacking in
justification that there was an error well understood and comprehended in
existing law beyond any possibility for fairminded disagreement.” Harrington,
131 S. Ct. at 786-87 (emphasis added).

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The first step in determining whether a state court unreasonably applied
clearly established federal law is to identify the Supreme Court holding that the
state court supposedly unreasonably applied. See Valdez, 274 F.3d at 946
(citation omitted). In the instant case the relevant holding is that of Atkins v.
Virginia, 536 U.S. 304, 122 S. Ct. 2242 (2002).
In Atkins, the Supreme Court held that “death is not a suitable
punishment for a mentally retarded criminal.” Id. at 321, 122 S. Ct. at 2252. It
based this holding on its conclusion that the Eighth Amendment’s meaning is to
be drawn “from the evolving standards of decency that mark the progress of a
maturing society.” Id. at 311-12, 122 S. Ct. at 2247. To determine what
“evolving standards of decency” would dictate in this context, the Court turned
to a consideration of “the judgment of legislatures that have addressed the
suitability of imposing the death penalty on the mentally retarded[.]” Id. at 313,
122 S. Ct. at 2247. After considering these judgments, the Court stated that “a
national consensus” had developed against the imposition of the death penalty
on the mentally retarded. Id. at 316, 122 S. Ct. at 2249.
While it found that there was a national consensus opposing the execution
of the mentally retarded, the Court acknowledged that there existed
disagreement “in determining which offenders are in fact retarded.” Id. at 317,
122 S. Ct. at 2250. In addition, it observed that “[n]ot all people who claim to be
mentally retarded will be so impaired as to fall within the range of mentally
retarded offenders about whom there is a national consensus.” Id. Rather than
formulating a rule for what subset of those who claimed to be mentally retarded
would be ineligible for the death penalty, the Court left to the states “‘the task
of developing appropriate ways to enforce the constitutional restriction upon

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[their] execution of sentences.’” Id. (quoting Ford v. Wainwright, 477 U.S. 399,
405, 416-17, 106 S. Ct. 2595, 2605 (1986)); see, e.g., Hill v. Humphrey, ___ F.3d
___, 2011 WL 5841715, at *6, 24 (11th Cir. Nov. 22, 2011) (en banc) (stating that
the United States Supreme Court “did not provide definitive procedural or
substantive guides for determining when a person” is mentally retarded and
holding that the Georgia Supreme Court did not violate any “clearly established”
federal law by upholding Georgia’s reasonable doubt standard for establishing
mental retardation).
Petitioner argues that Atkins requires state courts to apply the clinical
definitions of mental retardation promulgated by the American Association on
Mental Retardation (“AAMR”) and American Psychological Assocation (“APA”)
in evaluating murderers like Petitioner for possible mental retardation.
Petitioner relies in particular on footnote 22 of Atkins, which noted, in the course
of recounting the perceived national consensus, that state definitions of mental
retardation “generally conform . . . to the clinical definitions set forth” by the
AAMR and APA. Atkins, 536 U.S. at 317 n.22, 122 S. Ct. at 2250 n.22. This
means the Texas court’s analysis unreasonably applied Atkins’ holding,
Petitioner concludes, because he believes the state court analysis does not
conform with the AAMR and APA definitions, under which he contends he is
retarded.
To evaluate his claim, we turn to the TCCA’s decision and its grounding
in Ex parte Briseno, 135 S.W.3d 1 (2005). Petitioner specifically alleges that the
TCCA’s reliance on the Briseno factors for determining his retardation, rather
than the AAMR definition, was an unreasonable application of and contrary to
Atkins. We disagree. It is impossible to conclude that the state court’s analysis

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here, and its reliance on the factors outlined in Briseno, resulted in a decision
that was based on an unreasonable application of Atkins’s holding.
Before Atkins, the Texas legislature determined that to be classified as
retarded, a person must prove three facts by a preponderance of the evidence:
(a) significantly subaverage general intellectual functioning (proven by showing
an IQ below 70) and (b) deficits in adaptive behavior that (c) originated during
the developmental period (before age 18). See T EX. H EALTH & S AFETY C ODE
§ 591.003(13). This definition is almost identical to the AAMR definition of
mental retardation. The Texas Court of Criminal Appeals adopted the AAMR
definition of retardation for death penalty cases in Briseno. 135 S.W.3d at 8.
The Briseno court recognized that the AAMR definition was designed for
the purpose of providing social services, not for the purposes of determining
whether a person was “so impaired as to fall within the range of mentally
retarded offenders about whom there is national consensus.” It also recognized
that determining deficits in adaptive behavior (the second element) was highly
subjective. Id at 8. To account for these weaknesses in definition, the Briseno
court listed seven factors to flesh out the AAMR definition to determine whether
the convict falls within Atkins so as to be protected against the death penalty.
The court held:

The adaptive behavior criteria [second element] are
exceedingly subjective, and undoubtedly experts will be found to
offer opinions on both sides of the issue in most cases. There are,
however, some other evidentiary factors which factfinders in the
criminal trial context might also focus upon in weighing evidence as
indicative of mental retardation or of a personality disorder:

• Did those who knew the person best during the
developmental stage—his family, friends, teachers,

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employers, authorities—think he was mentally
retarded at that time, and, if so, act in accordance with
that determination?
• Has the person formulated plans and carried them
through or is his conduct impulsive?
• Does his conduct show leadership or does it show that
he is led around by others?
• Is his conduct in response to external stimuli rational
and appropriate, regardless of whether it is socially
acceptable?
• Does he respond coherently, rationally, and on point
to oral or written questions or do his responses wander
from subject to subject?
• Can the person hide facts or lie effectively in his own
or others’ interests?
• Putting aside any heinousness or gruesomeness
surrounding the capital offense, did the commission of
that offense require forethought, planning, and complex
execution of purpose?

135 SW.3d 1, 8 (2005). The Briseno court, in other words, fashioned these
evidentiary factors as a means “of developing appropriate ways to enforce the
constitutional restriction” set out in Atkins. And on their face, nothing about
them contradicts Atkins, as they were developed explicitly to comply with
Atkins.1
1
Indeed, the Briseno factors obviously evoke Atkins’s language which, in turn, evokes
the AAMR findings. The first Briseno factor, regarding developmental stages, ties to the
Atkins discussion of the onset of mental retardation before age 18. 536 U.S. at 318. The
second and third, regarding impulsive behavior and leadership, tie to the Atkins note that the
retarded “often act on impulse rather than pursuant to a premeditated plan, and that in group
settings they are followers rather than leaders.” Id. The fourth, regarding rational actions
and social propriety, ties to the Atkins discussion of “understand[ing] the reactions of others.”
Id. The fifth, regarding focused responses to questions, evokes the Atkins discussion of
“diminished capacities to understand and process information, to communicate . . . .” Id. The
sixth, concerning the ability to deceive, seems related to Atkins’s mention of “capacit[y] to
understand and process information, to communicate, to abstract from mistakes and learn
from experience, to engage in logical reasoning . . . .” Id. And the seventh, involving

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This court has never cast doubt on this approach. To the contrary, in
Clark v. Quarterman, this court held that “it is not ‘clearly established Federal
law as determined by the Supreme Court of the United States’ that state court
analysis of subaverage intellectual functioning must precisely track the AAMR’s
recommended approach.” 457 F.3d at 445. Clark specifically rejected
Petitioner’s argument that “the Texas courts must apply the approach
articulated by the [AAMR], which dictates that IQ examiners account for the
appropriate confidence band.” Id. If Texas need not follow AAMR procedures
when determining subaverage intelligence (a relatively objective determination),
then it would be senseless to think Texas must follow AAMR procedures when
determining deficits in adaptive behavior (a far more subjective determination).
In light of this court’s previous treatment of the Briseno factors, the
Supreme Court’s broad holding in Atkins, and the irrelevance for the purposes
of this inquiry of Atkins’ dicta (such as footnote 22), we conclude that the
application of the Briseno factors, even in the absence of specific employment of
the AAMR’s methodology for determining deficiencies in adaptive behavior,
cannot be an “unreasonable application” of Atkins’ broad holding. Atkins clearly
did not hold—and Petitioner does not even assert that Atkins held—that states
must employ the AAMR or APA definitions of mental retardation, let alone that
they must employ the same underlying clinical analysis that the AAMR and
APA use to determine which patients meet each prong of those organizations’
definitions; the absence of such a holding is determinative here.

forethought and planning, seems tied to Atkins’s mention of action “pursuant to a
premeditated plan.” Id. The Briseno factors thus are not arbitrary creations of the Texas
judiciary but rather carefully constructed considerations that tie directly to Atkins.

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This analysis also disposes of Petitioner’s overlapping argument that the
state court decision was “contrary to” clearly established federal law. A state
court’s decision is “contrary to” clearly established federal law if “it relies on
legal rules that directly conflict with prior holdings of the Supreme Court or if
it reaches a different conclusion than the Supreme Court on materially
indistinguishable facts.” Busby, 359 F.3d at 713. For the same reasons that
employment of the Briseno factors to determine adaptive functioning is not an
unreasonable application of Atkins, the Briseno factors themselves do not
“contradict” the Supreme Court’s holding in Atkins. See Terry Williams,
529 U.S. at 405, 120 S. Ct. at 1519 (holding state court decision is “contrary”
when it “applies a rule that contradicts the governing law set forth in our
cases”). This will come as no surprise, since this court has already concluded
that the Briseno is not “contrary to” Atkins in precisely this regard. See Woods
v. Quarterman, 493 F.3d 580, 587 n.6 (5th Cir. 2007) (“[Petitioner] also argues
that Ex parte Briseno, relied on by the state habeas court, is contrary to Atkins
in the way it allows courts to evaluate limitations in adaptive behavior. . . . We
find nothing in Briseno that is inconsistent with Atkins in this regard.”).
III. Section 2254(d)(2) Claims
With Section 2254(d)(1) unavailable as a means for obtaining federal
habeas relief, Petitioner must rely on Section 2254(d)(2), but ultimately in vain.
Section 2254(d)(2) excepts from the section’s general prohibition on habeas relief
cases where the adjudication of the claim in state court “resulted in a decision
that was based on an unreasonable determination of the facts in light of the
evidence presented in the State court proceeding.” 28 U.S.C. § 2254(d)(2). The
TCCA concluded that Petitioner lacked the deficits in adaptive behavior which,

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combined with his subaverage intellectual ability,2 would have yielded the
characteristics of mental retardation that render him not morally culpable of a
capital crime. Petitioner, on the other hand, argues that the VABS test is
dispositive: Under AAMR guidelines, a person with a VABS score of 57 and an
IQ test of 69 usually would be classified as mildly mentally retarded. Petitioner
argues that the Briseno factors are not adequate tools to determine whether a
person is retarded, and that the TCCA’s determination was unreasonable.
We must consider these claims through AEDPA’s discriminating lens,
noting that “relief may not be granted unless the decision was based upon an
unreasonable determination of the facts in light of the evidence presented in the
State court proceedings. A factual determination made by a state court must be
rebutted by clear and convincing evidence.” Clark, 457 F.3d at 443. “Factual
determinations by state courts are presumed correct absent clear and convincing
evidence to the contrary, § 2254(e)(1), and a decision adjudicated on the merits
in a state court and based on a factual determination will not be overturned on
factual grounds unless objectively unreasonable in light of the evidence
presented in the state-court proceeding, § 2254(d)(2).” Miller-El v. Cockrell,
537 U.S. 322, 340. As factfinder, the trial court is entitled to deference in
credibility determinations. Thompson v. Keohane, 516 U.S. 99, 111, 116 S. Ct.
457, 465 (1995) (quoting Miller v. Fenton, 474 U.S. 104, 114, 106 S. Ct. 445, 452
(1985)). “The question of whether a defendant suffers from mental retardation
involves issues of fact, and thus is subject to a presumption of correctness that

2
Chester’s IQ tests have resulted in varying numbers, but most of those numbers
would qualify him as mentally retarded under the AAMR definition if coupled with deficits in
adaptive behavior.

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must be rebutted by clear and convincing evidence under Section 2254 (e)(1).”
Maldonado v. Thaler, 625 F.3d 229, 236 (5th Cir 2010).
Accordingly, the state courts’ factual determination is presumed correct
unless Petitioner rebuts it with clear and convincing evidence. The state trial
court relied on three pieces of evidence to determine that Petitioner had no
significant deficits in adaptive behavior:

$ Expert testimony stated that Chester could communicate
clearly, understood current, topical matters, and understood
his current legal situation.
$ Chester’s criminal spree demonstrated the ability to plan,
avoid detection, and lie.
$ Chester attempted to escape police custody by lying about the
location of the hidden murder weapon so that he could grab it.

Petitioner responds that the Briseno factors and the state’s evidence only
focus on recent events (the crimes and recent interviews) as opposed to his full
history. Petitioner presented (and represents in his petition) the following
evidence:

$ The Vineland Adaptive Behavior Survey score of 57. Under
AAMR guidelines, this indicates that Chester has deficits in
adaptive behavior.
$ Expert testimony from Dr. Orloff.
$ Testimony from family members that Chester was always
“stupid.”
$ Testimony from school personnel stating that Chester was
stupid or retarded.
$ Evidence that Chester enrolled and participated in the
Mentally Retarded Offenders Program of the Texas
Department of Criminal Justice.

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The state trial court found, however, that Petitioner’s evidence was
unpersuasive or not credible. It discounted the family and school administrator’s
testimony as indicative only of a learning disability, not retardation. Further,
the court found that the family had an incentive to lie. Similarly, it found that
Dr. Orloff’s testimony was not credible, due to his insufficient exposure to
Petitioner and to his lesser credentials. Also, Petitioner’s enrollment in the
Mentally Retarded Offenders Program was not dispositive because official policy
allowed non-retarded convicts to participate.
The Texas Court of Criminal Appeals, while acknowledging that test
scores alone might have indicated mental retardation, nevertheless was
compelled to find that the evidence supported the trial court’s finding that
Petitioner is not mentally retarded.3 Petitioner has offered no “clear and
convincing evidence” rebutting the underlying findings or the ultimate finding
against mental retardation. While a different factfinder might reach a different
conclusion than the state courts, this court only reviews the proceedings to
determine whether Petitioner presented clear and convincing evidence that
rebuts the presumption that the state trial court’s determination was correct.
§§ 2254(d)(2), (e)(1). Petitioner failed to do so. Proceedings at the state trial
court were a battle between experts with additional testimony and evidence that

3
Petitioner and the dissent repeatedly claim that the state courts relied “solely” on the Briseno
factors. The dissent uses this device to assert that the TCCA’s decision is “contrary” to Atkins legally.
But the TCCA opinion (a) states the proper test, (b) states how the AAMR guidelines are informed by
the Briseno factors, and (c) corrects the state habeas court to confirm that Petitioner’s diagnostic tests
alone usually indicated a diagnosis of mild mental retardation. The court clearly took the test results
into account but found them overborne by evidence and credibility determinations of the trial court. This
is not “sole reliance” on improper factors but a faithful application of the principle, acknowledged in
Atkins itself, that the adaptive functioning component of mental retardation is complex. The dissent
would, contrary to Atkins, either prevent the state court from applying its expertise here, or confine the
state “solely” to diagnostic test results in debatable cases.

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was inconclusive and invited credibility testing. It is not this court’s place to
second-guess the court’s credibility determinations.
This analysis conclusively establishes that § 2254(d)(2) avails Petitioner
nothing. But we wish to note a few striking facts from the record that highlight
the deficiency of petitioner’s claim that the state courts’ factual findings
regarding deficiencies in adaptive behavior were “unreasonable.” Petitioner
carefully cased the house of his victims, located the telephone box, cut the
telephone wires, entered through an unlocked door (presumably to avoid the
noise that would accompany breaking in), disguised himself in a ski mask, and
raped/sodomized the two women inside using all the precautions one might
expect to see from a clever criminal.
After murdering the girls’ uncle, Petitioner fired his gun into the locked
doors of the victim’s car, apparently reasoning that shooting a lock would break
it and cause it to fail. This was hardly the work of a person with diminished
mental capacity; it was problem-solving in response to a crisis.
Atkins explains:

[C]linical definitions of mental retardation require not only
subaverage intellectual functioning, but also significant limitations
in adaptive skills such as communication, self-care, and self-
direction that became manifest before age 18. Mentally retarded
persons frequently know the difference between right and wrong
and are competent to stand trial. Because of their impairments,
however, by definition they have diminished capacities to
understand and process information, to communicate, to abstract
from mistakes and learn from experience, to engage in logical
reasoning, to control impulses, and to understand the reactions of
others. There is no evidence that they are more likely to engage in
criminal conduct than others, but there is abundant evidence that
they often act on impulse rather than pursuant to a premeditated

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plan, and that in group settings they are followers rather than
leaders.

536 U.S. at 318, 122 S. Ct. at 2250 (emphasis added). It seems obvious that
Petitioner did not act on an impulse, but rather “pursu[ed] a premeditated plan,”
acting of his own volition rather than as a “follower[].” Id. Indeed, he
masterminded a sophisticated break-in and dealt with a crisis as it developed.
Nothing about this crime suggests Petitioner had difficulties “process[ing]
information” or “engag[ing] in logical reasoning.” Id.4
Of course, the Petitioner’s burden here is much higher than simply
convincing us that Petitioner is not mentally retarded under Atkins. He has to
show by clear and convincing evidence that the state court’s determination was
unreasonable; he falls far short of this burden.
CONCLUSION
Because the TCCA’s decision was not contrary to or an unreasonable
application of clearly established federal law, and because it was not based on
an unreasonable factual determination in light of the evidence before it, we
AFFIRM the district court’s denial of habeas relief.

4
Petitioner’s other crimes, fully documented in the state court record and in the
TCCA’s opinion, further illustrate his cunning criminal calculations. As an example, the
murder of John Sepeda – to which Petitioner confessed – similarly involved the cutting of
telephone lines leading into a residence’s call box. And before murdering Cheryl DeLeon,
Petitioner unscrewed the lightbulb in the outdoor security light. Evidently, Petitioner was
able “to abstract from mistakes and learn from experience . . . .” Atkins, 536 U.S. at 318,
122 S. Ct. at 2250.

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 No. 08-70023

DENNIS, Circuit Judge, dissenting.
I respectfully dissent because the majority opinion affirms a Texas Court
of Criminal Appeals (TCCA) death penalty judgment that is contrary to the
federal law clearly established by Atkins v. Virginia, 536 U.S. 304 (2002): When
Atkins banned the execution of mentally retarded offenders, it defined mental
retardation as generally conforming to the three-part clinical definitions set
forth by the American Association on Mental Retardation (AAMR) and the
American Psychiatric Association (APA), which were quoted by the Court in
Atkins. In the present case, the TCCA, instead of applying the “adaptive skill
areas” part of that definition, id. at 308 n.3, applied its own substantively
contrary state law, known as the “Briseno factors,” in erroneously deciding that
Elroy Chester failed to prove that he is mentally retarded. For this reason, I
would vacate the federal district court’s judgment affirming the TCCA’s
judgment and remand the case to the federal district court for further
proceedings applying the entire correct clinical definition of mental retardation
as required by Atkins.
In Atkins, the Supreme Court held that the Eighth Amendment’s
prohibition of “cruel and unusual punishments” bars the execution of mentally
retarded offenders. The Court reasoned that: (1) there is a national consensus
among state legislatures and Congress that the execution of mentally retarded
offenders is excessive punishment, id. at 314-16; (2) the statutory definitions of
“mental retardation” used by states in that national consensus are not identical,
but generally conform to, the clinical definitions of “mental retardation” set
forth by the AAMR and APA, id. at 317 n.22; and (3) the Supreme Court’s
independent evaluation of the issue revealed no reason for the Court to disagree

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with the national legislative consensus, id. at 321. Based on this rationale, the
Atkins Court concluded that the Eighth Amendment “‘places a substantive
restriction on the State’s power to take the life’ of a mentally retarded offender,”
id. (quoting Ford v. Wainwright, 477 U.S. 399, 405 (1986)), and that this
constitutional restriction protects individuals who “fall within the range of
mentally retarded offenders about whom there is a national consensus,” id. at
317. Further, Atkins made plain that the AAMR and APA “clinical definitions
of mental retardation require not only subaverage intellectual functioning, but
also significant limitations in adaptive skills such as communication, self-care,
and self-direction that became manifest before age 18.” Id. at 318.1 Thus, in
deciding whether a person is mentally retarded and therefore exempt from
execution under the Eighth Amendment, a state court must apply each of the
three prongs — subaverage intellectual functioning; adaptive functioning
limitations; and onset prior to age eighteen — of a definition that generally
conforms to the AAMR and APA clinical definitions of “mental retardation.”
In Atkins, the Court also concluded that “[n]ot all people who claim to be
mentally retarded will be so impaired as to fall within the range of mentally
retarded offenders about whom there is a national consensus. As was our
approach in Ford v. Wainwright with regard to insanity, ‘we leave to the State[s]
the task of developing appropriate ways to enforce the constitutional restriction

1
Authorities have used the terms “adaptive functioning,” “adaptive behavior,” and
“adaptive skills” to refer to this element of mental retardation. See Am. Ass’n on Mental
Retardation, Mental Retardation: Definition, Classification, and Systems of Supports 1 (10th
ed. 2002) [hereinafter AAMR-10] (referring to “limitations . . . in adaptive behavior as
expressed in conceptual, social, and practical adaptive skills”); Am. Psychiatric Ass’n,
Diagnostic and Statistical Manual of Mental Disorders 41 (4th ed., text rev. 2000) [hereinafter
DSM-IV-TR] (referring to “limitations in adaptive functioning in at least two of [eleven] skill
areas”); Am. Ass’n on Mental Retardation, Mental Retardation: Definition, Classification, and
Systems of Supports 5 (9th ed. 1992) [hereinafter AAMR-9] (referring to “limitations in two or
more of [ten] adaptive skill areas”). Neither the state nor Chester argues that these
terminological differences have any effect on the issues in this appeal. Accordingly, this
opinion refers to adaptive functioning, adaptive behavior, and adaptive skills interchangeably.

20
 No. 08-70023

upon [their] execution of sentences.’” Id. at 317 (alterations in original) (citation
omitted) (quoting Ford, 477 U.S. at 416-17). In so doing, the Ford Court made
clear that when “the Eighth Amendment bars execution of a category of
defendants defined by their mental state[,] [t]he bounds of that category are
necessarily governed by federal constitutional law.” Ford, 477 U.S. at 419
(Powell, J., concurring in part and concurring in the judgment, but speaking for
the majority on this point).2 Thus, by closely following Ford, Atkins signals
clearly that federal constitutional law governs the bounds of the category of
mentally retarded individuals who are exempt from execution, although the
states, within the confines of due process, may devise procedures to govern
mental retardation determinations.
Our en banc court and panels have adopted this understanding of Atkins.
See Moore v. Quarterman, 533 F.3d 338, 341 (5th Cir. 2008) (en banc) (“Atkins
specifically reserved to the states the adoption of procedures to implement its
new constitutional rule . . . .” (emphasis added)); Wiley v. Epps, 625 F.3d 199,
207 (5th Cir. 2010) (“[E]ven though Atkins left to the states the job of
implementing procedures for determining who is mentally retarded, ‘it was
decided against the backdrop of the Supreme Court’s and lower court’s due
process jurisprudence.’” (emphasis added) (quoting Rivera v. Quarterman, 505
F.3d 349, 358 (5th Cir. 2007))). Accordingly, the states retain substantial
discretion to create appropriate procedures, but they may not substantively
redefine mental retardation so as to permit the execution of those who “fall
within the range of mentally retarded offenders about whom there is a national
consensus.” Atkins, 536 U.S. at 317.

2
See Panetti v. Quarterman, 551 U.S. 930, 949 (2007) (“Justice Powell’s opinion
constitutes ‘clearly established’ law for purposes of [28 U.S.C.] § 2254 and sets the minimum
procedures a State must provide to a prisoner raising a Ford-based competency claim.”)

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 No. 08-70023

In Atkins, the Supreme Court quoted and referred to the AAMR definition
of mental retardation as follows: “Mental retardation refers to substantial
limitations in present functioning. It is characterized by [(1)] significantly
subaverage intellectual functioning, [(2)] existing concurrently with related
limitations in two or more of the following applicable adaptive skill areas:
communication, self-care, home living, social skills, community use,
self-direction, health and safety, functional academics, leisure, and work[; and
(3)] Mental retardation manifests before age 18.” 536 U.S. at 309.3
The Texas habeas trial court, in considering Chester’s habeas petition, did
not apply the second element of the AAMR definition to determine if Chester had
“related limitations in two or more of the following applicable adaptive skill
areas: communication, self-care, home living, social skills, community use,
self-direction, health and safety, functional academics, leisure, and work.”
Instead, the trial court applied the “Briseno factors,” a series of questions
originally suggested by the TCCA in Ex parte Briseno, 135 S.W.3d 1 (Tex. Crim.
App. 2004), which the TCCA itself has described as being “non-diagnostic
criteria.” Ex parte Van Alstyne, 239 S.W.3d 815, 820 (Tex. Crim. App. 2007).
Although the factors were initially conceived of as “evidentiary factors which
factfinders . . . might also focus upon in weighing evidence as indicative of
mental retardation or of a personality disorder,” Briseno, 135 S.W.3d at 8, the
TCCA in the present case used the Briseno factors as a substantive part of its
mental retardation definition, instead of the second prong of the AAMR
definition (the AAMR clinical adaptive skills criteria) to determine that Chester
had not proved he had adaptive skills deficits, and, therefore, that Chester failed

3
In Atkins, the Court also quoted and referred to the similar APA clinical definition of
mental retardation. Because the Texas courts have adverted only to the AAMR clinical
definition, and the two clinical definitions are substantively the same, I set forth and refer
here only to the AAMR clinical definition of mental retardation.

22
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to prove he is mentally retarded. See Ex parte Chester, No. AP-75037, 2007 WL
602607 (Tex. Crim. App. Feb. 28, 2007) (unpublished).
Chester introduced evidence that he scored under 70 in 4 of the 5 full-scale
IQ tests that he has taken since the age of seven years, and scored 57 on the
Vineland Adaptive Behavior Survey (VABS), a clinical adaptive functioning test.
His evidence showed he has been unable to live or work independently, and his
experts and lay witnesses related that he suffered from mild mental retardation
and was deficient in several adaptive behavioral areas. The state habeas trial
court, which gave no reason for applying the Briseno factors to the exclusion of
the AAMR adaptive skills criteria and the VABS test results, found that Chester
failed to disprove any of the Briseno factors, was therefore not limited in
adaptive functioning, and thus not mentally retarded for this reason alone. See
Chester, 2007 WL 602607, at *4. The TCCA affirmed, approving of the trial
court’s use of the Briseno factors to the exclusion of clinical adaptive skills
criteria to define mental retardation. Id. at *9. The U.S. District Court denied
federal habeas relief, on the ground that Chester’s application failed under the
seventh Briseno factor alone. Chester v. Quarterman, No. 5:05cv29, 2008 WL
1924245, at *7 (E.D. Tex. Apr. 29, 2008) (unpublished).
The TCCA’s decision was contrary to the federal law that was clearly
established by the Supreme Court in Atkins. Under Atkins, state courts must
apply a mental retardation definition that generally conforms to all three parts
of the clinical AAMR or APA definitions. The TCCA’s unique nondiagnostic
Briseno factors are more constricted than, unrelated to, and substantively
contrary to the adaptive deficits criteria identified in the second prongs of the
AAMR and APA clinical definitions of mental retardation. Exclusively applying
the Briseno factors to assess the substantive adaptive skills prong of the mental
retardation definition inevitably leads to anomalous and unreliable results,
including the execution of offenders who should be classified as mentally

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retarded and shielded from execution under Atkins and the comprehensive
clinical definitions quoted therein. In other words, by affirming the Texas courts’
erroneous use of the Briseno factors in place of the adaptive skills prong of the
substantive three-part rule defining mental retardation, the majority allows
those state courts to circumvent the constitutional rule of Atkins and to use their
more constricted definition of mental retardation to exclude substantial numbers
of mentally retarded offenders from protection from execution under the Eighth
Amendment.4 Because the decisions of the TCCA and the federal district court
are based on the same error of clear constitutional law, the judgment of the
federal district court should be set aside and the case should be remanded to it
for further proceedings generally conforming to the clinical definitions of mental
retardation as required by Atkins.
I.
The petitioner, Elroy Chester, robbed and raped two young women at
gunpoint in their home. When the women’s uncle unexpectedly arrived at the
house, Chester shot and killed him. He pleaded guilty to the crime of capital
murder and was sentenced to death by a Texas jury in 1998. His conviction and
sentence were affirmed on direct appeal. Chester then sought post-conviction
relief at the state and federal levels on the grounds that he could not be executed
because he is mentally retarded.
Chester’s federal habeas petition was pending in 2002 when the Supreme
Court held in Atkins that the Eighth Amendment forbids the execution of

4
At least one study suggests that Texas may be favorably resolving far fewer Atkins
claims than the national average. As of 2011, of the 81 Texas petitioners whose Atkins
collateral review claims have been resolved, only 14 (17% of the total) have been successful.
This “is significantly lower than the ‘national average’ success rate of thirty-eight percent
identified in a 2008 study of states that had resolved Atkins claims.” Peggy M. Tobolowsky,
A Different Path Taken: Texas Capital Offenders’ Post-Atkins Claims of Mental Retardation,
39 Hastings Const. L.Q. 1, 71 & nn. 203-04, 373-74 (2011) (citing John H. Blume et al., An
Empirical Look at Atkins v. Virginia and its Application in Capital Cases, 76 Tenn. L. Rev.
625, 628-29, 637 (2009)).

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mentally retarded offenders. Consequently, Chester’s petition was dismissed
without prejudice to allow him to renew his claim for state post-conviction relief
on the basis of Atkins. Chester v. Cockrell, No. 02-41152, 62 F. App’x 556 (5th
Cir. Feb. 26, 2003).
The TCCA granted Chester leave to file a successive state habeas petition
and remanded his case to the state trial court for further proceedings. The trial
court held an evidentiary hearing on the Atkins claim. In order to prove that he
was mentally retarded, under Atkins, 536 U.S. 304, and Briseno, 135 S.W.3d 1,5
Chester was required to show by a preponderance of the evidence that he had (1)
significantly subaverage general intellectual functioning and (2) related
limitations in adaptive functioning, (3) the onset of which had occurred before
Chester reached age 18. Briseno, 135 S.W.3d at 7. Chester introduced
substantial evidence of his mental retardation, including full-scale IQ scores of

5
In Ex parte Briseno, the TCCA determined how, in the absence of guidance from the
state legislature, Texas courts would procedurally “‘enforce the constitutional restriction’”
imposed by Atkins. Briseno, 135 S.W.3d at 5 (quoting Atkins, 536 U.S. at 317). The Briseno
court held that Atkins claims in habeas corpus applications would be decided by judges rather
than juries, id. at 11, and that the defendant would bear the burden of proof to establish
mental retardation by a preponderance of the evidence, id. at 12.
In addition to establishing these procedural specifications, the Briseno court described
“some other evidentiary factors which factfinders in the criminal trial context might also focus
upon in weighing evidence as indicative of mental retardation or of a personality disorder.” Id.
at 8. They include: (1) “Did those who knew the person best during the developmental stage
. . . think he was mentally retarded at that time, and, if so, act in accordance with that
determination; (2) “Has the person formulated plans and carried them through or is his
conduct impulsive?”; (3) “Does his conduct show leadership or does it show that he is led
around by others?”; (4) “Is his conduct in response to external stimuli rational and appropriate,
regardless of whether it is socially acceptable?”; (5) “Does he respond coherently, rationally,
and on point to oral or written questions or do his responses wander from subject to subject?”;
(6) “Can the person hide facts or lie effectively in his own or others’ interests?”; (7) “Putting
aside any heinousness or gruesomeness surrounding the capital offense, did the commission
of that offense require forethought, planning, and complex execution of purpose?” Id. at 8-9.
As will be discussed more fully below, the Briseno court did not initially present these
factors as a substitute or alternative definition of mental retardation, but only as additional
factors which a court “might also” take into consideration. The Briseno factors differ
substantially from the adaptive skill areas identified by the AAMR and APA in the clinical
definitions of mental retardation. See infra Sections IV, VI.A.

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69 at age seven, 59 at age twelve, 77 at age thirteen, 69 at age eighteen, and 66
at age twenty-nine and a score of 57 on VABS, a standardized test of adaptive
functioning. The Texas Department of Criminal Justice administered one of
these IQ tests – on which Chester scored a 69 – and the VABS test in 1987, when
Chester was eighteen years old. The State’s own expert testified that a person
with those test scores would be correctly diagnosed as mentally retarded. In
addition, an expert retained by Chester testified that he was indeed mentally
retarded. Chester also supplied other evidence tending to show that he suffers
from limitations in adaptive functioning. He presented evidence that he was
placed in special education early in schooling and admitted into the prison
Mentally Retarded Offenders Program (MROP) at approximately age eighteen;
achievement testing in prison placed him at third grade levels or below. Two of
his sisters testified regarding his adaptive behavior deficits, including his
inability to live or work independently. A special education teacher testified
regarding his limited abilities at school. One expert diagnosed Chester as
mentally retarded based on a review of his records, interviews with Chester, and
observation of the State expert’s interview with him. Another expert classified
him as mildly mentally retarded based on a review of his MROP records.
Chester asserted that he demonstrated deficits regarding the broader
conceptual and practical adaptive skill areas, as well as the specific skill areas
of communication, work, functional academics, self-direction, and community
use. The trial court, adopting the entirety of the prosecution’s proposed findings
of fact and conclusions of law, concluded that Chester had failed to carry his
burden of proof as to either of the first two elements of mental retardation:
significantly subaverage general intellectual functioning and related limitations
in adaptive functioning. The trial court found that Chester failed to prove that
he had adaptive skill deficits but it did not apply the clinical AAMR criteria to
make this finding. Instead, it applied the Briseno “evidentiary factors” and

26
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concluded that, under the Briseno factors, Chester was not limited in adaptive
functioning and therefore failed to satisfy the adaptive functioning prong of the
tripartite clinical definitions of mental retardation. He therefore was found to
be not mentally retarded. If the trial court had applied the clinical adaptive
functioning criteria instead, Chester’s evidence arguably would have shown he
satisfied this prong as well as the other two and that he is mentally retarded.
On appeal, the TCCA partly overruled the trial court’s findings and
conclusions. Chester, 2007 WL 602607. The TCCA held that Chester “has met his
burden in regard to demonstrating significant limitations in intellectual
functioning,” id. at *3, and that “there is no dispute as to the third part of the
test, that the evidence in favor of a finding of mental retardation occurred and
was recorded before the applicant reached the age of eighteen,” id. at *2. Thus,
the TCCA held that Chester had satisfied the first and third prongs of the
definition of mental retardation. However, the TCCA denied habeas relief
because it concluded that Chester had not “[s]hown [s]ignificant [d]eficits in
[a]daptive [b]ehavior” as required by the second prong, id. at *4, and he had
therefore not carried the burden of showing that he was mentally retarded. In
reaching this conclusion, the TCCA did not consider the AAMR’s or APA’s
clinical definitions of mental retardation, but relied exclusively on the factors
that had previously been presented in Briseno as merely “some other evidentiary
factors which factfinders in the criminal trial context might also focus upon in
weighing evidence as indicative of mental retardation or of a personality
disorder,” Briseno, 135 S.W.3d at 8. See Chester, 2007 WL 602607, at *4-5.
Chester then filed another federal habeas petition. In that proceeding, the
state did not dispute that the evidence of his mental deficits developed before he
was eighteen years old or “that Chester suffers from significantly sub-average
intellectual functioning.” Chester, 2008 WL 1924245, at *2. But the district court
departed even further than the state courts from the Atkins clinical definitions

27
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of mental retardation, expressly holding that a finding as to just one of the seven
Briseno factors was a sufficient basis for denying an Atkins claim: “[A]n
affirmative finding as to the seventh and final Briseno evidentiary factor is
sufficient by itself to uphold a denial of relief in a habeas corpus proceeding.” Id.
at *7.6
Thus, the district court held that the TCCA’s “rejection of [Chester’s]
mental retardation claim is neither inconsistent with, nor the result of an
unreasonable application of, clearly established federal law,” and denied habeas
relief. Id.7
Chester now appeals from the district court’s order denying habeas relief.
II.
“In a habeas corpus appeal, we review the district court’s findings of fact
for clear error and review its conclusions of law de novo, applying the same
standard of review to the state court’s decision as the district court.” Beazley v.
Johnson, 242 F.3d 248, 255 (5th Cir. 2001) (quoting Thompson v. Cain, 161 F.3d
802, 805 (5th Cir. 1998)) (internal quotation marks omitted).8 I conclude that

6
The seventh Briseno evidentiary factor is as follows: “Putting aside any heinousness
or gruesomeness surrounding the capital offense, did the commission of that offense require
forethought, planning, and complex execution of purpose?” Briseno, 135 S.W.3d at 8-9.
7
However, the district court granted Chester a certificate of appealability as to three
issues, the first two of which are as follows:
1. The state courts’ determination that Mr. Chester is not mentally retarded is
unreasonable in light of the evidence presented in the state court and violates
the Eighth Amendment by permitting the execution of a mentally retarded
defendant.
2. As a way to assess significantly subaverage adaptive functioning, the Briseno
factors have no basis in the scientific literature and conflict with the accepted
definitions of mental retardation recognized and relied on in Atkins v. Virginia,
making the state courts’ exclusive reliance on the Briseno factors an
unreasonable application of federal law clearly established in Atkins and
violating the Eighth Amendment by permitting the execution of a mentally
retarded defendant.
8
Because the TCCA was the last state court to address Chester’s arguments, we review
the decision of that court. See Wood v. Quarterman, 491 F.3d 196, 202 (5th Cir. 2007) (focusing
on whether “the last reasoned state court decision” was “contrary to, [or] an unreasonable
application of, federal law”); see also Watson v. Anglin, 560 F.3d 687, 690 (7th Cir. 2009) (“We

28
 No. 08-70023

Chester has shown that his habeas petition should be granted under the
“contrary to” clause of AEDPA, 28 U.S.C. § 2254(d)(1). Therefore, I need not
consider whether he also satisfies the unreasonable application” clause of
AEDPA, 28 U.S.C. § 2254(d)(1), and need not review the district court’s findings
of fact for clear error.
“Under the Antiterrorism and Effective Death Penalty Act (AEDPA), a
federal court may not grant § 2254 habeas relief on any ground previously
disposed of on the merits by a state court unless the state decision ‘was contrary
to, or involved an unreasonable application of, clearly established [f]ederal law,
as determined by the Supreme Court of the United States,’ or ‘was based on an
unreasonable determination of the facts in light of the evidence presented in the
[s]tate court proceeding.’” Geiger v. Cain, 540 F.3d 303, 306-07 (5th Cir. 2008)
(alterations in original) (quoting 28 U.S.C. § 2254(d)(1)-(2)); see also Woods v.
Quarterman, 493 F.3d 580, 584 (5th Cir. 2007). “A state court decision is
contrary to clearly established federal law if it ‘applies a rule that contradicts the
governing law set forth in [Supreme Court] cases,’ or if the state court confronts
a set of facts that are materially indistinguishable from a decision of [the
Supreme Court] and nevertheless arrives at a result different from [the Court’s]
precedent.’ A state court decision involves an unreasonable application of clearly
established federal law if the state court ‘correctly identifies the governing legal
rule but applies it unreasonably to the facts of a particular prisoner’s case . . . .’”
Williams v. Quarterman, 551 F.3d 352, 358 (5th Cir. 2008) (alterations in

review the decision of the last state court to address [the petitioner’s] arguments.”); Mark v.
Ault, 498 F.3d 775, 783 (8th Cir. 2007) (“[W]e apply the AEDPA standard to . . . the ‘last
reasoned decision’ of the state courts.” (quoting Ylst v. Nunnemaker, 501 U.S. 797, 804
(1991))); Joseph v. Coyle, 469 F.3d 441, 450 (6th Cir. 2006) (“[T]he decision we review is that
of ‘the last state court to issue a reasoned opinion on the issue.’” (quoting Payne v. Bell, 418
F.3d 644, 660 (6th Cir. 2005))); Barker v. Fleming, 423 F.3d 1085, 1091 (9th Cir. 2005) (“When
more than one state court has adjudicated a claim, we analyze the last reasoned decision.”).

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original) (citations omitted) (quoting Williams v. Taylor, 529 U.S. 362, 405-08
(2000)).
III.
In Atkins, the Supreme Court early in its opinion set forth in full the
generally accepted clinical definitions of mental retardation:
The American Association on Mental Retardation (AAMR)
defines mental retardation as follows: “Mental retardation refers to
substantial limitations in present functioning. It is characterized by
significantly subaverage intellectual functioning, existing
concurrently with related limitations in two or more of the following
applicable adaptive skill areas: communication, self-care, home
living, social skills, community use, self-direction, health and safety,
functional academics, leisure, and work. Mental retardation
manifests before age 18.” Mental Retardation: Definition,
Classification, and Systems of Supports 5 (9th ed. 1992).
The American Psychiatric Association’s [(APA)] definition is
similar: “The essential feature of Mental Retardation is significantly
subaverage general intellectual functioning (Criterion A) that is
accompanied by significant limitations in adaptive functioning in at
least two of the following skill areas: communication, self-care, home
living, social/interpersonal skills, use of community resources,
self-direction, functional academic skills, work, leisure, health, and
safety (Criterion B). The onset must occur before age 18 years
(Criterion C). Mental Retardation has many different etiologies and
may be seen as a final common pathway of various pathological
processes that affect the functioning of the central nervous system.”
Diagnostic and Statistical Manual of Mental Disorders 41 (4th ed.
2000). “Mild” mental retardation is typically used to describe people
with an IQ level of 50-55 to approximately 70. Id., at 42-43.
Atkins, 536 U.S. at 308 n.3. The Court then surveyed developments in state and
federal law that showed a growing nationwide consensus that mentally retarded
defendants should not be executed. See id. at 313-16. Beginning with a Georgia
law enacted in 1988, the Court counted eighteen states, along with the federal
government, which had enacted legislation prohibiting the execution of mentally
retarded defendants. See id. at 313-15. Furthermore, the Court observed that

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“even in those States that allow the execution of mentally retarded offenders, the
practice is uncommon[:] . . . only five [states] have executed offenders possessing
a known IQ less than 70” since 1989. Id. at 316.
The Court therefore concluded that “a national consensus has developed
against” the execution of mentally retarded defendants. Id. “To the extent there
is serious disagreement about the execution of mentally retarded offenders, it is
in determining which offenders are in fact retarded. . . . Not all people who claim
to be mentally retarded will be so impaired as to fall within the range of
mentally retarded offenders about whom there is a national consensus.” Id. at
317. The Court noted that “[t]he [states’] statutory definitions of mental
retardation are not identical, but generally conform to the clinical definitions”
promulgated by the AAMR and the APA. Id. at 317 n.22. Thus, the Court’s
holding that “a national consensus has developed,” id. at 316, was based on
statutes which employed “definitions of mental retardation” that “generally
conform to the clinical definitions” quoted above, id. at 317 n.22.
As an additional step in its reasoning, the Court undertook an
“independent evaluation of the issue.” Id. at 321. In this step, the Court reasoned
that “by definition,” people with mental retardation have certain characteristics
that make their execution cruel and unusual. Id. at 318. These characteristics
include “diminished capacities to understand and process information, to
communicate, to abstract from mistakes and learn from experience, to engage
in logical reasoning, to control impulses, and to understand the reactions of
others.” Id. Because of these characteristics, “executing the mentally retarded
will not measurably further the goal of deterrence,” id. at 320, and “the lesser
culpability of the mentally retarded offender . . . does not merit that form of
retribution.” Id. at 19. Moreover, mentally retarded defendants “face a special
risk of wrongful execution” because of “the possibility of false confessions, [and]
the lesser ability of mentally retarded defendants to make a persuasive showing

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of mitigation.” Id. at 320-21. Therefore, the Court concluded, there was “no
reason to disagree with the judgment of ‘the legislatures that have recently
addressed the matter’ and concluded that death is not a suitable punishment for
a mentally retarded criminal.” Id. (quoting Enmund v. Florida, 458 U.S. 782,
801 (1982)).
In short, the holding of Atkins is that the Eighth Amendment prohibits the
execution of individuals who are “so impaired as to fall within the range of
mentally retarded offenders about whom there is a national consensus.” Id. at
317. And the Court described the parameters of that “national consensus” as
“generally conform[ing] to the clinical definitions” of mental retardation used by
the AAMR and APA. Id. at 317 & n.22.
The Court refrained from setting forth procedures for determining whether
a particular defendant is “so impaired as to fall within the range of mentally
retarded offenders about whom there is a national consensus.” Id. at 317.
Rather, it declared, “we leave to the States the task of developing appropriate
ways to enforce the constitutional restriction upon their execution of sentences.”
Id. (quoting Ford, 477 U.S. at 405) (brackets and internal quotation marks
omitted).
The Atkins Court noted that this was the same “approach” that the Court
had previously followed “in Ford v. Wainwright with regard to insanity.” 536
U.S. at 317. We have previously observed that “Ford is instructive” in Atkins
cases “because of the similarity of the competency and mental retardation issues:
both decisions affirmatively limit the class of persons who are death penalty
eligible.” Rivera, 505 F.3d at 358. The Court’s opinions in Atkins and Ford both
expressly announced “that the Constitution ‘places a substantive restriction on
the State’s power to take the life’” of certain offenders. Atkins, 536 U.S. at 321
(quoting Ford, 477 U.S. at 405); see also Panetti, 551 U.S. at 957 (same).

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In Ford, Justice Powell’s controlling concurring opinion 9 explained that
when “the Eighth Amendment bars execution of a category of defendants defined
by their mental state[,] [t]he bounds of that category are necessarily governed
by federal constitutional law.” 477 U.S. at 419. Further, the Panetti Court
explained that Ford “broadly identif[ied]” a “substantive standard for
incompetency”; applying this substantive standard, the Panetti Court “reject[ed]
the standard followed by the Court of Appeals” as being inconsistent with Ford.
551 U.S. at 960. Thus, it is clear under both Ford and Panetti that the definition
of incompetency to be executed is a matter of federal substantive constitutional
law. Because Atkins expressly adopted Ford’s approach by announcing “a
substantive restriction,” 536 U.S. at 321, while giving states procedural room to
“develop[] appropriate ways to enforce” that restriction, id. at 317, it follows that
under Atkins, too, the substantive definition of mental retardation for Eighth
Amendment purposes is a matter of federal constitutional law.
Atkins identified a substantive standard for mental retardation by
announcing that states may not execute offenders who are “so impaired as to fall
within the range of mentally retarded offenders about whom there is a national
consensus.” Atkins, 536 U.S. at 317. The Court explained that the “national
consensus” was based on state-law definitions of mental retardation that
“generally conform to the clinical definitions” in the AAMR-9 and DSM-IV-TR,
which the Court quoted in full in its opinion. Id. at 308 n.3, 317 & n.22.
Therefore, in order to “appropriate[ly] . . . enforce the constitutional restriction”
imposed by Atkins, id. at 317 (quoting Ford, 477 U.S. at 416), states must apply
definitions of mental retardation that “generally conform to the clinical
definitions,” id. at 317 n.22.10

9
See Panetti, 551 U.S. at 949 (“Justice Powell’s opinion [in Ford] constitutes ‘clearly
established law’ for purposes of [28 U.S.C.] § 2254 . . . .”).
10
See Pruitt v. State, 834 N.E.2d 90, 108 (Ind. 2005) (plurality opinion) (“[T]he Eighth
Amendment must have the same content in all United States jurisdictions. . . . Because Atkins

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IV.
In 2004, the Texas Court of Criminal Appeals issued an opinion declaring
how the Texas courts would “enforce the constitutional restriction” under Atkins.
Briseno, 135 S.W.3d at 5 (quoting Atkins, 536 U.S. at 317). The court observed
that it had “previously employed the definitions of ‘mental retardation’ set out
by the AAMR, and that contained in section 591.003(13) of the Texas Health and
Safety Code. Under the AAMR definition, mental retardation is a disability
characterized by: (1) ‘significantly subaverage’ general intellectual functioning;
(2) accompanied by ‘related’ limitations in adaptive functioning; (3) the onset of
which occurs prior to the age of 18. As noted above, the definition under the
Texas Health and Safety Code is similar . . . .” Id. at 7 (footnotes omitted) (citing,
inter alia, AAMR-9, supra note 1, at 5).11 Accordingly, the court concluded that
“[u]ntil the Texas Legislature provides an alternate statutory definition of
‘mental retardation’ for use in capital sentencing, we will follow the AAMR or
section 591.003(13) criteria in addressing Atkins mental retardation claims.” Id.
at 8.
However, the Briseno court expressed some concern with the “adaptive
behavior criteria” in the AAMR definition,12 which it considered to be

explains that state statutes that provided the ‘national consensus’ against the execution of the
mentally retarded ‘generally conform’ to the AAMR or DSM-IV definitions, we conclude that
Atkins requires at least general conformity with those definitions, but allows considerable
latitude within that range. . . . [W]e think that the prohibition of the execution of the mentally
retarded must have some content. There may be some flexibility in determining mental
retardation, but we think that if a state’s definition of mental retardation were completely at
odds with definitions accepted by those with expertise in the field the definition would not
satisfy the prohibition.”).
11
Section 591.003(13) of the Texas Health and Safety Code states: “‘mental retardation’
means significantly subaverage general intellectual functioning that is concurrent with deficits
in adaptive behavior and originates during the developmental period.”
12
As previously noted, the AAMR’s 1992 definition of mental retardation, as quoted by
the Supreme Court in Atkins, includes an “adaptive functioning” prong, which requires
“limitations in two or more of the following applicable adaptive skill areas: communication,
self-care, home living, social skills, community use, self-direction, health and safety, functional
academics, leisure, and work.” Atkins, 536 U.S. at 308 n.3 (quoting AAMR-9, supra note 1, at
5). The AAMR issued a revised definition of mental retardation in 2002, see AAMR-10, supra

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“exceedingly subjective.” Id. at 8. For this reason, the court identified “some
other evidentiary factors which factfinders in the criminal trial context might
also focus upon in weighing evidence as indicative of mental retardation or of a
personality disorder.” Id.13 Those additional factors are as follows:
• Did those who knew the person best during the developmental
stage — his family, friends, teachers, employers, authorities —
think he was mentally retarded at that time, and, if so, act in
accordance with that determination?
• Has the person formulated plans and carried them through or is
his conduct impulsive?
• Does his conduct show leadership or does it show that he is led
around by others?
• Is his conduct in response to external stimuli rational and
appropriate, regardless of whether it is socially acceptable?
• Does he respond coherently, rationally, and on point to oral or
written questions or do his responses wander from subject to
subject?
• Can the person hide facts or lie effectively in his own or others’
interests?

note 1, but the differences between the AAMR’s 1992 and 2002 criteria for adaptive
functioning or adaptive behavior are not relevant to this appeal.
13
The Briseno court may have mistakenly assumed that a defendant cannot suffer
from both mental retardation and a personality disorder, when in fact individuals often suffer
both from mental retardation and personality disorders. “[T]he scientific and clinical
definitions emphasize that individuals with mental retardation often have mental disorders
as well. No reasonable clinician would have determined that [a defendant] did not have mental
retardation merely because the evidence also supported a diagnosis of antisocial personality
disorder.” John H. Blume et al., Of Atkins and Men: Deviations from Clinical Definitions of
Mental Retardation in Death Penalty Cases, 18 Cornell J.L. & Pub. Pol’y 689, 692 (2009). The
AAMR has authoritatively explained that “[t]he types of mental health disorders are the same
in people with and people without mental retardation.” AAMR-10, supra note 1, at 172. “The
prevalence of mental health disorders among individuals with mental retardation is difficult
to estimate due to problems in sampling and diagnosis. In general, mental health disorders
are much more prevalent in this population compared to the general population.” Id. Thus, an
offender might well be correctly diagnosed with both mental retardation and a personality
disorder. See Lambert v. State, 126 P.3d 646, 659 (Okla. Crim. App. 2005) (“Mental retardation
and mental illness are separate issues. It is possible to be mentally retarded and mentally
ill.”).

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 No. 08-70023

• Putting aside any heinousness or gruesomeness surrounding the
capital offense, did the commission of that offense require
forethought, planning, and complex execution of purpose?
Id. at 8-9. Although the TCCA identifies the Briseno factors as “adaptive
functioning” criteria, the factors bear no resemblance to the AAMR or APA
adaptive functioning criteria. The Briseno court cited no sources or authorities
for the proposition that these “other evidentiary factors” are an accurate or
useful way to tell whether a person is genuinely mentally retarded; thus, the
factors appear to be wholly the TCCA’s own creation. These factors are “non-
diagnostic,” Van Alstyne, 239 S.W.3d at 820, and based on the judges’
impressions and assumptions about mental retardation. See Blume, supra note
13, at 712. The court gave no explanation of how the factors are any less
“subjective” than the criteria for adaptive functioning in the AAMR’s definition
of mental retardation, and they are not based on or drawn from the adaptive
functioning skill areas identified by the AAMR or the APA. See Atkins, 536 U.S.
at 308 n.3; see also supra note 1.14
After setting forth these evidentiary factors, the TCCA went on to
determine the procedural means by which Atkins claims in state habeas
petitions would be resolved. The court decided that “Atkins does not require a
jury determination of mental retardation in a post-conviction proceeding,” id. at
9, and that “[t]he defendant bears the burden of proof, by a preponderance of the
evidence, to establish that he is mentally retarded,” id. at 12 (bold face removed).
The court then concluded that the petitioner in that case, Jose Garcia Briseño,

14
It is also unclear how the Briseno factors could be used as an independent, conclusive
way to determine whether a person has significant limitations in adaptive functioning. The
AAMR-9, DSM-IV-TR, and AAMR-10 definitions of mental retardation clearly specify how
their adaptive functioning criteria are to be used: a person fulfills the criteria if he or she has
significant limitations in two of ten, or two of eleven, or one of three, areas. By contrast, the
Briseno factors do not indicate whether a defendant must negate one factor, or a majority of
them, or all seven, or if some factors have more weight than others.

36
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had failed to prove by a preponderance of the evidence that he was mentally
retarded. See id. at 14-18.
In summary, as relevant here, the Briseno court first determined that
Texas courts “w[ould] follow the AAMR or section 591.003(13) criteria in
addressing Atkins mental retardation claims,” and then mentioned seven “other
evidentiary factors which factfinders . . . might also focus upon” in determining
whether a defendant has the limitations in adaptive behavior that are required
for a finding of mental retardation. Id. at 8.
V.
In the present case, the TCCA held that Chester fulfilled two of the three
requirements of mental retardation: significantly subaverage intellectual
functioning and onset before age 18.15 It is undisputed in this appeal that
Chester meets those requirements. Whether Chester is mentally retarded
therefore depends on whether he meets the one remaining requirement:
significant limitations in adaptive functioning. In the state habeas proceedings,
Chester presented a substantial amount of evidence that tended to prove that
he does have significant limitations in adaptive functioning, under the standard
clinical definitions of mental retardation to which the national consensus
generally conforms, see Atkins, 536 U.S. at 317 & n.22. However, the TCCA
concluded that Chester is not mentally retarded — a conclusion which was based
entirely and exclusively on the TCCA’s application of the Briseno evidentiary
factors. Chester, 2007 WL 602607, at *4-5, *9.
Chester provided the state courts with factual evidence and expert
testimony indicating that he has significant limitations in adaptive functioning

15
The state trial court, on habeas, adopted the prosecution’s proposed findings of fact
and conclusions of law in their entirety and thereby held that Chester did not have
significantly subaverage intellectual functioning. However, the TCCA observed that “the trial
court’s findings on the applicant’s [IQ] test scores were in conflict with the record” and
concluded that Chester “has met his burden in regard to demonstrating significant limitations
in intellectual functioning.” Chester, 2007 WL 602607, at *2-3.

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as defined by the AAMR and APA criteria.16 Notably, he received a score of 57
on the VABS test, which is a clinical method of assessing a person’s level of
adaptive functioning for the purpose of diagnosing mental retardation.17 The
TCCA observed that “even the State’s expert witness acknowledged that a
person with a Vineland score of 57, combined with an IQ score of 69 as measured
at the same time, would be correctly diagnosed as mildly mentally retarded.”
Chester, 2007 WL 602607, at *3. These two scores were obtained in 1987 by the
Texas Department of Criminal Justice, when Chester was eighteen years old. He
was admitted to the department’s Mentally Retarded Offender Program at that
time. Id. That was eleven years before Chester committed the murder for which

16
Chester also argues that the evidence shows that he is mentally retarded under the
revised definition promulgated by the AAMR’s tenth edition in 2002. See generally AAMR-10,
supra note 1. The questions raised in this appeal do not turn on any differences between the
AAMR’s 2002 definition and the earlier definitions that the Supreme Court quoted in Atkins.
Thus, we have no occasion to consider what the result should be if a defendant were to show
that he was retarded under one clinical definition but not under another one. Cf., e.g., Wiley
v, 625 F.3d at 216 n.13 (noting that expert witnesses in that case “indicated that their
diagnoses of [the defendant] were the same under both” the AAMR’s 1992 and 2002 definitions
of the adaptive behavior prong); In re Hearn, 418 F.3d 444, 445 (5th Cir. 2005) (citing the
AAMR-10 in support of a general definition of mental retardation: “Mental retardation is a
disability characterized by three criteria: significant limitation in intellectual functioning,
significant limitation in adaptive behavior and functioning, and onset of these limitations
before the age of 18”); United States v. Hardy, 762 F. Supp. 2d 849, 879 (E.D. La. 2010) (“While
these differences in definition deserve note, they are ultimately of no consequence to the
Court’s task. Just as in Wiley, . . . the court need not decide which is preferable or correct,
because the differences between them are mostly theoretical. Both the APA and AAMR direct
clinicians to the same standardized measures of adaptive behavior, such as the Vineland
Adaptive Behavior Scales-II . . . .”).
17
Courts, including the TCCA, have often considered VABS test scores to be a valid way
of assessing the adaptive functioning prong of mental retardation. See, e.g., Van Alstyne, 239
S.W.3d at 820 n.12 (“The Vineland Adaptive Behavior Test is one of the recognized
standardized scales for measuring adaptive deficits.” (citing Ex parte Blue, 230 S.W.3d 151,
165 n.55 (Tex. Crim. App. 2007))).
Moreover, the AAMR favors the use of standardized tests, such as the VABS, as a way
to diagnose mental retardation: “For the diagnosis of mental retardation, significant
limitations in adaptive behavior should be established through the use of standardized
measures normed on the general population, including people with disabilities and people
without disabilities. On these standardized measures, significant limitations in adaptive
behavior are operationally defined as performance that is at least two standard deviations
below the mean . . . .” AAMR-10, supra note 1, at 76 (emphasis added).

38
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he was sentenced to death, and fifteen years before the Supreme Court decided
Atkins; thus, Chester could not have been faking mental retardation to avoid the
death penalty. The TCCA’s opinion gave no specific reason for disbelieving or
disregarding Chester’s VABS score of 57. Neither has the State of Texas given
us any reason why the score would not be reliable.
Chester also presented substantial evidence of limitations in at least four
out of the AAMR’s ten “adaptive skill areas”: communication, home living,
functional academics, and work. Atkins, 536 U.S. at 308 n.3 (quoting AAMR-9,
supra note 1, at 5).18 For instance, there was evidence that while growing up,
Chester had severe communication difficulties: he spoke in jumbled sentences
with misused words and a small vocabulary. His school diagnosed him with a
“serious communicative handicap” and provided therapy. Other children called
him “stupid” and “retarded.” He attended special education classes from third
through twelfth grades. All his classes were taught to him at his own academic
level, which was never higher than third grade. As an adult, when out of jail,
Chester never lived independently; never had a driver’s license or a bank
account; held only menial jobs; could not read or write well enough to fill out a
job application; and could not shop or cook by himself. At eighteen years of age
he could read “only small words” and could not name the months of the year,
according to the Texas Department of Criminal Justice’s assessment which
resulted in his being admitted to the MROP.19

18
The AAMR and APA definitions of mental retardation require that a person have
limitations in only two adaptive skill areas. Atkins, 536 U.S. at 308 n.3.
19
There are disputes about the significance of some of the evidence in the record. For
instance, Dr. Edward Gripon, the state’s mental retardation expert, testified that the correct
diagnosis for someone with an IQ score of 69 and a VABS score of 57 is mental retardation.
Yet he also testified that he did not think Chester was mentally retarded.
The state emphasizes that although Chester was placed in the MROP, he was officially
classified as having “borderline intellectual functioning” rather than mental retardation.
However, Dr. Henry Orloff, a psychologist who was the MROP’s director at the time, testified
that there was no basis for the diagnosis of borderline intellectual functioning, and that the
erroneous diagnosis had been allowed to stand because at that time, it made no practical

39
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Despite Chester’s VABS test score of 57 — which the state’s own expert
witness testified was low enough to require a diagnosis of mental retardation —
and despite his substantial evidence of adaptive functioning limitations in at
least four of the AAMR skill areas, the state courts relied exclusively on the
Briseno factors to determine that Chester did not meet this requirement of
mental retardation. Thus, the state courts did not use the Briseno factors in the
limited way in which the TCCA’s Briseno opinion announced that they would be
used — as “other evidentiary factors” that a court “might also focus upon” in
addition to the AAMR’s clinical definition. 135 S.W.3d at 8 (emphases added).
The TCCA in Briseno stated that it would apply the AAMR’s 1992
definition of mental retardation, which includes adaptive functioning criteria,
in Atkins cases. Id. The adaptive functioning prong of the AAMR’s 1992
definition of mental retardation, as quoted in Atkins, is satisfied by a finding of
“limitations in two or more of the following applicable adaptive skill areas:
communication, self-care, home living, social skills, community use, self-
direction, health and safety, functional academics, leisure, and work.” Atkins,
536 U.S. at 308 n.3 (quoting AAMR-9, supra note 1, at 5) (quotation marks
omitted). Similarly, the APA has stated that mentally retarded individuals will
have “significant limitations in adaptive functioning in at least two of the
following skill areas: communication, self-care, home living, social/interpersonal
skills, use of community resources, self-direction, functional academic skills,

difference.
The state also emphasizes that in school, Chester was categorized as being learning
disabled rather than mentally retarded. However, Chester counters that a diagnosis of
learning disability would be simply invalid in light of his consistently low IQ test results, since
a person with a learning disability by definition has a discrepancy between IQ and academic
achievement. The DSM-IV-TR explains: “Learning Disorders are diagnosed when the
individual’s achievement on individually administered, standardized tests in reading,
mathematics, or written expression is substantially below that expected for age, schooling, and
level of intelligence.” DSM-IV-TR, supra note 1, at 49 (emphasis added). By contrast, “In
Mental Retardation, learning difficulties are commensurate with general impairment in
intellectual functioning.” Id. at 51 (emphasis added).

40
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work, leisure, health, and safety.” Id. (quoting DSM-IV-TR, supra note 1, at 41
(quotation marks omitted). Yet the TCCA in this case made no attempt
whatsoever to determine whether Chester has significant limitations in two or
more of those areas of adaptive functioning.20 The state trial court likewise made
no such attempt.
Instead, the TCCA and the state trial court both treated their findings
under the Briseno factors as if they were a sufficient basis, standing alone, for
determining whether a person has significant limitations in adaptive
functioning. The courts did not employ — nor did they even mention — any of
the clinical definitions or criteria for adaptive functioning limitations. The trial
court stated: “This Court’s review of evidentiary factors relating to adaptive
behavior suggested relevant by the Court of Criminal Appeals in Ex parte
Briseno weigh conclusively against Applicant’s argument that he is mentally
retarded.” State v. Chester, No. 76044-B, slip op. at 25 (Crim. Dist. Ct. Jefferson
Cnty., Tex. July 26, 2004). The TCCA stated: “The trial court’s findings
addressed all seven evidentiary factors listed in Briseno, and noted carefully how
the applicant had failed to persuade the trial court on each one.” Chester, 2007
WL 602607, at *4. The TCCA, in effect, dispensed with any measurement of
“adaptive functioning” as it is conceived of by the clinical mental retardation
definitions and the adaptive functioning criteria contained therein.
The federal district court, in denying Chester habeas relief, likewise made
no attempt to determine whether Chester has significant limitations in adaptive
functioning according to a rule generally conforming to the clinical definition of
mental retardation. The federal district court relied entirely on the seventh

20
Nor did the TCCA make any attempt to apply any other clinical criteria for assessing
adaptive functioning, such as the AAMR’s 2002 definition, which requires “performance that
is at least two standard deviations below the mean of either (a) one of the following three types
of adaptive behavior: conceptual, social, or practical, or (b) an overall score on a standardized
measure of conceptual, social, and practical skills.” AAMR-10, supra note 1, at 14.

41
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Briseno factor, and nothing else, as the adaptive functioning test: “an affirmative
finding as to the seventh and final Briseno evidentiary factor is sufficient by
itself to uphold a denial of relief in a habeas corpus proceeding.” Chester, 2008
WL 1924245, at *7. Thus, not only did the federal district court disregard the
AAMR and APA clinical criteria that were used by the Atkins Court to define
mental retardation, but it disregarded six of the seven Briseno factors as well.
VI.
A.
The TCCA’s decision in the present case is contrary to the clear holding of
the Court in Atkins. “A state court decision is contrary to clearly established
federal law if it ‘applies a rule that contradicts the governing law set forth in
[Supreme Court] cases . . . .’” Williams v. Quarterman, 551 F.3d at 358 (first
alteration in original) (quoting Williams v. Taylor, 529 U.S. at 405). The TCCA
applied a rule of decision using the Briseno factors as its exclusive basis for
holding that Chester does not have significant limitations in adaptive
functioning and that he is therefore not mentally retarded for Eighth
Amendment purposes. By so holding, the TCCA adopted and applied a rule of
decision that the Briseno “other evidentiary factors,” standing alone, can be used
to determine that an offender does not have significant limitations in adaptive
functioning and is therefore not mentally retarded, even when the offender has
presented strong evidence that he satisfies all the AAMR or APA clinical criteria
for mental retardation.
The TCCA’s rule of decision is contrary to Atkins because, as explained
above, Atkins held that the Eighth Amendment imposes a “substantive
restriction,” 536 U.S. at 321, which prevents states from executing offenders who
are “so impaired as to fall within the range of mentally retarded offenders about
whom there is a national consensus,” id. at 317. In order to “appropriate[ly] . . .
enforce th[is] constitutional restriction,” states must apply definitions of mental

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retardation for Eighth Amendment purposes that reflect the “national
consensus” by “generally conform[ing] to the [AAMR and APA] clinical
definitions” of mental retardation. Id. at 317 & n.22. The rule applied by the
TCCA in this case involved a radical departure from general conformity with
those clinical definitions of mental retardation. It redefined the adaptive
functioning element in such a way that it clearly contradicts and fails to carry
out Atkins’s mandate to protect from execution all offenders who fall within the
national consensus’s understanding of mental retardation that generally
conforms to the AAMR and APA definitions.
The Briseno evidentiary factors, standing alone, cannot be used to
accurately determine that a person does not have significant limitations in
adaptive functioning according to the national consensus’s understanding of
mental retardation that the Atkins Court identified. This is because the Briseno
evidentiary factors are substantively very different from, and ask different
questions than, the AAMR and APA criteria. For instance, the Briseno factors
do not consider, and therefore cannot determine, whether a person has
significant limitations in the adaptive skill areas of self-care, home living,
community use, health and safety, functional academics, leisure, or work. The
AAMR-9 and APA criteria or precepts generally conforming to them require only
that a person must have significant limitations in two out of ten or eleven
adaptive skill areas (as well as showing significantly subaverage intellectual
functioning and onset before age 18). The AAMR and APA have noted that
mentally retarded individuals have strength areas and that the most
appropriate way to identify adaptive functioning deficits is to focus on the
individual’s limitations. See AAMR-10, supra note 1, at 8 (“[P]eople with mental
retardation are complex human beings who likely have certain gifts as well as
limitations . . . . These may include strengths in social or physical capabilities,
strengths in some adaptive skill areas, or strengths in one aspect of an adaptive

43
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skill in which they otherwise show an overall limitation.”); Blume et al., supra
note 13, at 706, 710 (quoting AAMR-10, supra note 1, at 8); see also Holladay v.
Allen, 555 F.3d 1346, 1363 (11th Cir. 2009) (“Individuals with mental
retardation have strengths and weaknesses, like all individuals. Indeed, the
criteria for diagnosis recognizes this by requiring a showing of deficits in only
two of ten identified areas of adaptive functioning.”); Lambert, 126 P.3d at 651
(“Unless a defendant’s evidence of particular limitations is specifically
contradicted by evidence that he does not have those limitations, then the
defendant’s burden is met no matter what evidence the State might offer that
he has no deficits in other skill areas.”).21
The Briseno factors, used exclusive of the clinical definitions, operate in
a significantly different manner. As in this case, if the factfinder concludes that
the petitioner met one of the Briseno factors even in a limited period of time or
situation, the factfinder may then overlook the petitioner’s limitations and
conclude that the petitioner is not mentally retarded. Thus, a person could easily
21
The AAMR’s 2002 definition of mental retardation incorporates the following
explanation:
Assumption 3: “Within an individual, limitations often coexist with strengths.”
This means that people with mental retardation are complex human beings who
likely have certain gifts as well as limitations. Like all people, they often do
some things better than other things. Individuals may have capabilities and
strengths that are independent of their mental retardation. These may include
strengths in social or physical capabilities, strengths in some adaptive skill
areas, or strengths in one aspect of an adaptive skill in which they otherwise
show an overall limitation.
AAMR-10, supra note 1, at 8. In accordance with this principle, the Oklahoma Court of
Criminal Appeals, has explained that evidence regarding an offender’s criminal activity is
relevant for Atkins purposes only insofar as it tends to show that the offender does or does not
have limitations in the areas specified by the clinical definitions: “Lambert was required to
show . . . that he had limitations in adaptive functioning in two of nine areas . . . . None of the
evidence of criminal activity went to any of Lambert’s claims of adaptive function limitations.
Thus, strictly speaking, none of it was relevant to disprove those claims.” Lambert, 126 P.3d
at 656.
The Briseno evidentiary factors, because they focus heavily on isolated instances of a
person’s behavior, by design are not meant to indicate whether a person meets the standard
clinical criteria for mental retardation, which assess an individual’s limitations in adaptive
functioning based on his or her typical behavior.

44
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have significant limitations in two or more of these areas and yet be determined
not to be mentally retarded by a court that relied exclusively on the Briseno
evidentiary factors. Exclusive reliance on the Briseno factors renders evidence
of significant limitations meaningless, and is directly contrary to the clinical
definitions.
Moreover, at least some of the Briseno factors are concerned with aspects
of a person’s behavior that bear no relation to mental retardation as defined by
the AAMR and APA. The second Briseno evidentiary factor (“Has the person
formulated plans and carried them through or is his conduct impulsive?”)
describes impulsivity as a sign of mental retardation, but the DSM-IV-TR flatly
contradicts this: “Some individuals with Mental Retardation are passive, placid,
and dependent, whereas others can be aggressive and impulsive.” DSM-IV-TR,
supra note 1, at 44. The fourth and fifth Briseno evidentiary factors (“Is his
conduct in response to external stimuli rational and appropriate, regardless of
whether it is socially acceptable? Does he respond coherently, rationally, and on
point to oral and written questions or do his responses wander from subject to
subject?”) treat rationality and coherent communication as being inconsistent
with mental retardation, but the clinical definitions do not indicate that
mentally retarded people cannot communicate or behave rationally. On the
contrary, the DSM-IV-TR states that people with mild mental retardation —
who are “the largest segment (about 85%) of those with the disorder” —
“typically develop social and communication skills” and “usually achieve social
and vocational skills adequate for minimum self-support.” DSM-IV-TR, supra
note 1, at 43.
Finally, the Briseno evidentiary factors also substantially depart from
clinical definitions of mental retardation because they focus on isolated instances
of a person’s behavior rather than on a person’s typical, day-to-day level of
adaptive functioning. The seventh Briseno factor especially focuses on how the

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underlying capital crime was committed. This focus on isolated events – and
especially on extraordinary events, like a situation in which a person commits
murder — runs directly contrary to the clinical definitions’ emphasis on day-to-
day functioning and on the fact that mentally retarded people, like anyone else,
have strengths as well as limitations, in particular circumstances as well as in
different skill areas. See Holladay, 555 F.3d at 1363 (criticizing the state’s expert
for her “predominant focus on [the offender’s] actions surrounding the crime,”
which “suggest[ed] that she did not recognize [that people with mental
retardation have strengths as well as weaknesses]”); see also Caroline
Everington & J. Gregory Olley, Implications of Atkins v. Virginia: Issues in
Defining and Diagnosing Mental Retardation, 8 J. Forensic Psychol. Prac., no.
1, 2008, at 1, 11 (“[P]erhaps most important, adaptive behavior is the
individual’s typical performance in his/her community setting. The details of the
crime cannot be considered to be a sample of typical behavior.”).
As the Supreme Court explained in Williams v. Taylor, 529 U.S. at 405
(O’Connor, J., concurring in part and concurring in the judgment, and speaking
for the court on this point), “a state-court decision is contrary to this Court’s
precedent if the state court arrives at a conclusion opposite to that reached by
this Court on a question of law” or “if the state court confronts facts that are
materially indistinguishable from a relevant Supreme Court precedent and
arrives at a result opposite to ours.” Further elaborating, the Court stated:
The word “contrary” is commonly understood to mean “diametrically
different,” “opposite in character or nature,” or “mutually opposed.”
Webster’s Third New International Dictionary 495 (1976). The text
of § 2254(d)(1) therefore suggests that the state court’s decision
must be substantially different from the relevant precedent of this
Court. . . . A state-court decision will certainly be contrary to our
clearly established precedent if the state court applies a rule that
contradicts the governing law set forth in our cases.
Id. (emphasis added).

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Then, the Court gave two examples to clarify its meaning. First, it
explained that:
If a state court were to reject a prisoner’s claim of ineffective
assistance of counsel on the grounds that the prisoner had not
established by a preponderance of the evidence that the result of his
criminal proceeding would have been different, that decision would
be “diametrically different,” “opposite in character or nature,” and
“mutually opposed” to our clearly established precedent because we
held in Strickland that the prisoner need only demonstrate a
“reasonable probability that . . . the result of the proceeding would
have been different.”
Id. at 405-06 (quoting Strickland v. Washington, 466 U.S. 668, 694 (1984)). The
Court then provided an example of when a state law is not “contrary to” a clearly
established federal law:
[A] run-of-the-mill state-court decision applying the correct legal
rule from our cases to the facts of a prisoner’s case would not fit
comfortably within § 2254(d)(1)’s “contrary to” clause. Assume, for
exam ple, that a state-court decision on a prisoner’s
ineffective-assistance claim correctly identifies Strickland as the
controlling legal authority and, applying that framework, rejects the
prisoner’s claim. Quite clearly, the state-court decision would be in
accord with our decision in Strickland as to the legal prerequisites
for establishing an ineffective-assistance claim, even assuming the
federal court considering the prisoner’s habeas application might
reach a different result applying the Strickland framework itself. It
is difficult, however, to describe such a run-of-the-mill state-court
decision as “diametrically different” from, “opposite in character or
nature” from, or “mutually opposed” to Strickland, our clearly
established precedent.
Id. 406.
Applying the Court’s precepts to the present case, it is clear that the TCCA
has arrived at a decision that is contrary to Atkins because it applied a rule that
contradicts the governing law set forth in Atkins. Similarly to the first example
given in Williams v. Taylor, the TCCA rejected Chester’s Atkins claim on the
grounds that he had not established his limitations in adaptive functioning by

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proving he was so limited or deficient according to the state-law Briseno factors.
That decision is “diametrically different,” “opposite in character or nature,” and
“mutually opposed” to the Court’s clearly established precedent because the
Court held in Atkins that Chester need only demonstrate that he has adaptive
functioning deficits according to a definition that generally conforms to the
AAMR or APA clinical definitions. The Briseno factors do not generally conform
to, and indeed are “substantially different” from, either the AAMR or APA
adaptive functioning criteria. See Williams v. Taylor, 529 U.S. at 405.
In other words, this is not a run-of-the-mill state-court decision in which
the state court correctly identified the clinical adaptive functioning prong of
Atkins’s clinical definition of mental retardation and, applying that framework,
rejected the prisoner’s claim. Instead, the TCCA in this case disregarded the
adaptive functioning framework recognized by the Court in Atkins and applied
the state-court-created Briseno factors, which are “diametrically different,”
“opposite in character or nature,” and “mutually opposed” to a definition that
generally conforms to the clinical criteria recognized by the Court in Atkins for
defining mental retardation. Specifically, the TCCA’s decision was contrary to
Atkins itself, where the Court held that a defendant may demonstrate his
adaptive functioning deficits by showing limitations in specific skill areas that
generally conform to the AAMR or APA clinical mental retardation definitions.
Thus, because the Briseno evidentiary factors are substantively different
from and contrary to the clinical and diagnostic approaches to determining
deficits in adaptive functioning, when they are used as the sole measure of a
person’s adaptive functioning, rather than concordantly with clinically
standardized test results and professionally accepted criteria, they cannot
accurately determine whether a person is mentally retarded in accordance with
the national consensus’s understanding of mental retardation that the Supreme
Court identified in Atkins.

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B.
In addition to being contrary to Atkins, the TCCA decision in this case did
not follow its own earlier opinion in Briseno in which it had stated that it would
apply the AAMR definition of mental retardation or the similar Texas Health
Code § 591.003(13) definition. Briseno, 135 S.W.3d at 7-8. The Briseno court
mentioned some “other evidentiary factors” that a court “might also focus upon,”
id. at 8 (emphases added), but it did not suggest that those factors could be used
as a substitute for substantive clinical criteria in determining whether an
offender has significant limitations in adaptive functioning. In this case, the
TCCA disregarded the Atkins second prong clinical criteria altogether and used
Briseno’s “other evidentiary factors” as its sole basis for determining that
Chester does not have significant limitations in adaptive functioning. The
district court took this substantive definition change a step further and held that
an affirmative finding of the seventh Briseno factor alone can serve as the sole
basis for affirming the TCCA.
The three-judge dissent in Lizcano v. State, No. AP-75879, 2010 WL
1817772 (Tex. Crim. App. May 5, 2010) (Price, J., concurring and dissenting)
(unpublished), made the point forcefully that the TCCA majority, in using or
allowing the use of the Briseno factors to the exclusion of clinical diagnostic
criteria to determine whether a petitioner has satisfied the second prong of the
tripartite definition of mental retardation, contradicts both Atkins and Briseno.
In Lizcano, as in Chester, the factfinder used the Briseno factors to the exclusion
of clinical diagnostic criteria to reject the petitioner’s mental retardation claim
and to affirm his death sentence. The dissent acknowledged that there may be
“fodder” in the Briseno decision to support the Lizcano majority’s argument that
the jury is not “bound by the diagnostic criteria,” id. at *34, but then correctly
argued that such a belief runs contrary to established federal law: “Atkins
adopted a categorical prohibition. It was founded upon the Supreme Court’s

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ratification of the prevalent legislative judgment that it is inappropriate to
execute mentally retarded offenders. That legislative judgment comprehended
mental retardation in essentially the same ‘clinical’ terms as the AAMR’s and
APA’s diagnostic criteria.” Id. at *35.
The Lizcano dissent argued that the TCCA was not “justif[ied] [in its]
apparent grant of latitude to fact-finders in Texas to adjust the clinical criteria
for adaptive deficits to conform to their own normative judgments with respect
to which mentally retarded offenders are deserving of the death penalty and
which are not.” Id. In failing to “anchor the fact-finder’s decision on the specific
diagnostic criteria,” id., the majority acted unconstitutionally: “Even if the
Supreme Court in Atkins ‘did not mandate the application of a particular mental
health standard for mental retardation, . . . it did recognize the significance of
professional standards and framed the constitutional prohibition in medical
rather than legal terms.’ It would be anomalous to allow the fiat of a fact-finder
to undermine the essentially diagnostic character of the inquiry. We should not
. . . permit a [fact-finder] capriciously to deviate from the specific diagnostic
criteria in order to conform to its own normative, unnecessarily subjective, and
certainly unscientific judgment regarding who deserves the death penalty.” Id.
(first alteration in original) (footnotes omitted).
In summary, in order to determine whether Chester is mentally retarded
and protected from execution under Atkins, the state courts were
constitutionally obligated to employ a definition of mental retardation that
would identify and protect the class of offenders covered by Atkins’s “substantive
restriction on the State’s power to take [a] life” — namely, those offenders who
are “so impaired as to fall within the range of offenders about whom there is a
national consensus.” Atkins, 536 U.S. at 317, 321. However, in their adjudication
of Chester’s claim, the state courts transformed the Briseno evidentiary factors
into a stand-alone substantive test for the adaptive functioning prong of the

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mental retardation definition, a test that does not “generally conform to the
clinical definitions,” id. at 317 n.22, and hence cannot accurately determine
whether an offender falls within the class that is protected by Atkins. The state
courts did this even though Chester presented standardized test scores and other
evidence tending to show that he satisfied the clinical criteria for adaptive
functioning limitations (as well as the other two prongs of mental retardation,
which he has undisputedly established). Therefore, the state courts’ decision that
Chester is not mentally retarded was “contrary to” Atkins, under 28 U.S.C. §
2254(d)(1), because the state court applied a rule that contradicted the governing
law clearly set forth in Atkins.
VII.
The issue presented by this case is not whether a state or federal court
must strictly apply the AAMR or APA clinical definitions of mental retardation
in deciding Atkins claims — as the majority suggests — but rather whether a
court must apply a definition that generally conforms to those clinical
definitions, or whether a court can disregard or depart freely from them and
make up its own unscientific and non-clinical definition of mental retardation
that contradicts the definitions to which the national consensus generally
conforms. Atkins requires that states apply a definition that “generally
conforms” to the AAMR and APA clinical definitions and diagnostic assessments
of mental retardation, which the national consensus has embraced. In this case,
the TCCA utilized parts of the tripartite definition of mental retardation, but its
definition of the adaptive functioning prong does not generally conform to the
national consensus’s definition of this prong and in fact departs substantially
from the nationally accepted criteria for determining whether a petitioner has
adaptive functioning deficits.
The majority erroneously concludes that the Briseno factors provide a
constitutionally acceptable means of limiting the class of defendants who are

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death eligible, and that Chester’s claim must fail. There is a vast distance
between a holding requiring strict adherence to a clinical definition and a
holding that would allow states to develop their own definitions of mental
retardation without regard for the clinical definitions or the national consensus.
While the former is not required by Atkins, the latter clearly falls outside
Atkins’s constitutional bounds because Atkins requires that the state’s definition
“generally conform” to the clinical definitions that the national consensus relied
upon in narrowing the class of death eligible defendants to exclude mentally
retarded defendants.
The Atkins holding clearly prohibits the execution of mentally retarded
defendants. Although as in Ford, the Supreme Court left to the states the task
of enforcing this restriction, Atkins, 536 U.S. at 317, “[t]he bounds of that
category are necessarily governed by federal constitutional law.” Ford, 477 U.S.
at 419 (Powell, J., concurring in part and concurring in the judgment, and
speaking for the majority on this point). The prohibition becomes meaningless
unless it is moored to a generally agreed upon definition of “mental retardation.”
Yet this is what the majority does: it releases the definition from its moorings.
The TCCA should not be permitted to circumvent Atkins’s constitutional
prohibition by totally supplanting the definition of adaptive functioning that,
prior to Briseno, had been utilized by Texas courts and which “generally
conform[ed]” both with the AAMR clinical definition and with the national
consensus that had developed around the AAMR and APA definitions.
The majority does not attempt to argue that the Briseno factors, standing
alone, fall within the national consensus. Indeed, the opinion seems to suggest
that states are empowered to ignore the national consensus. This national
consensus tracks the “‘evolving standards of decency that mark the progress of
a maturing society,’” which underlies Eighth Amendment jurisprudence. Atkins,
536 U.S. at 312 (quoting Trop v. Dulles, 356 U.S. 86, 101 (1958)). States may not

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ignore it in favor of their own restrictions that would allow for the execution of
individuals that the national consensus has decided should not be executed. This
is clear from the text of Atkins, which left to the states only “‘the task of
developing appropriate ways to enforce the constitutional restriction upon [their]
execution of sentences.’” Atkins, 536 U.S. at 317 (alteration in original)
(emphasis added) (quoting Ford, 477 U.S. at 416-17). It does not give states the
power to define what the constitutional restriction is; that had already been
determined by the national consensus upon which the Atkins Court based its
holding.
In this case, the TCCA used the Briseno factors as a substitute for the
clinical definition that Texas had previously pledged to follow and to which the
national consensus generally conforms. It presents a “scientifically unsound and
Atkins-violative assessment[] of adaptive functioning.” Blume, supra note 13, at
706. Moreover, standing alone, the Briseno factors turn on its head the
consensus’s approach to determining whether the petitioner has significant
limitations in adaptive functioning. The AAMR and APA correctly assess
adaptive functioning by analyzing the petitioner’s limitations. According to the
AAMR, a person who is deficient in two out of the ten AAMR adaptive skill areas
may be categorized as having significant limitations in adaptive functioning. The
Briseno factors function in the opposite manner. According to the district court
below, which the majority today affirms, the fact finder may find that a
petitioner is not mentally retarded merely because he meets one of the seven
Briseno factors. Moreover, several of the Briseno factors are markedly different
from the clinical adaptive skill areas, and several are based on a person’s actions
in a single moment instead of over a person’s lifetime. In other words, if the
Briseno factors, standing alone, are allowed to replace an analysis that generally
conforms to the clinical definitions, a single area or moment of strength can
discount substantive evidence of significant limitations in numerous areas of

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adaptive functioning. See Blume, supra note 13, at 717-18. Furthermore, the
TCCA, in developing the Briseno factors, did not conduct an assessment of the
national consensus or draw from the clinical definitions of mental retardation
around which the national consensus has coalesced. The factors are unmoored
from the national consensus’s general understanding of what constitutes mental
retardation. Used alone, these factors may determine that a subclass of persons
protected by Atkins’s holding are, indeed, death eligible in Texas. The use of the
Briseno factors in the present case therefore is clearly “contrary to . . . clearly
established Federal law, as determined by the Supreme Court of the United
States.” 28 U.S.C. § 2254(d)(1).
VIII.
Chester’s claim that he is mentally retarded must be adjudicated in a
manner that is consistent with Atkins. The TCCA’s adjudication of Chester’s
claim was contrary to the law that Atkins clearly established. See Williams v.
Quarterman, 551 F.3d at 358 (5th Cir. 2008) (“A state court decision is contrary
to clearly established federal law if it ‘applies a rule that contradicts the
governing law set forth in [Supreme Court] cases . . . .’” (first alteration in
original) (quoting Williams v. Taylor, 529 U.S. at 405)). Accordingly, I would
vacate the judgment of the district court and remand this case to allow the
district court to determine, not inconsistently with this opinion and pursuant to
the federal law clearly established by the Supreme Court in Atkins, whether
Chester is mentally retarded under a definition of mental retardation that
“generally conform[s] to the clinical definitions” set forth in Atkins, 536 U.S. at
317 n.22, and thus “fall[s] within the range of mentally retarded offenders about
whom there is a national consensus,” id. at 317, and hence is protected from
execution by the Eighth Amendment.

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