concurring in part and dissenting in part.
I concur with Part II of Judge Woll-man’s opinion finding that Terrick Noon-er’s request to withdraw his habeas petition is not knowing and voluntary. I further concur that Arkansas’s victim impact is constitutional. However, I respectfully dissent from Part III-C of the majority’s opinion regarding Nooner’s ineffective assistance of counsel claim.
As part of their preparation for the trial, Nooner’s two appointed counsel learned that Nooner experienced a turbulent and troubled childhood which included child abuse, foster home placements, severe emotional and behavioral problems, school problems, substance abuse, and two hospitalizations at psychiatric institutions during Nooner’s early teenage years. Based on their observations of Nooner’s behavior, Nooner’s attorneys determined that he was competent to stand trial and did not request a competency evaluation. Likewise, relying upon their own observations of Nooner’s current behavior and their reading of a six-year old discharge report from one of the psychiatric institutions, Nooner’s attorneys did not request assistance of a psychiatric expert to examine Nooner for the purpose of preparing mitigating evidence during the penalty phase of the trial.
In the state court, the victim’s mother testified during the penalty phase of the trial and described the impact the murder had on her family. Nooner’s stepfather also gave testimony about Nooner’s troubled childhood, and to a lesser extent, about Nooner’s emotional problems. Nooner’s trial counsel attempted to persuade the jury that severe stress and his young age of twenty-two mitigated the crime. The jury heard no psychiatric evidence.
Nooner presented twelve independent claims of ineffective assistance of counsel at his post-conviction proceeding in state district court. Among other things, Noon-er claimed ineffective assistance because his attorneys failed to request a psychiatric evaluation to assess his competency to stand trial (the so-called “Act III” evaluation). Nooner also included a similar but independent claim of ineffective assistance based on his attorneys’ failure to request a psychological examination for the purpose of developing and presenting mitigating evidence during the penalty phase of his trial (the so-called “mitigation evaluation”).
In Nooner’s appeal to the Arkansas Supreme Court, Nooner abandoned his claim of ineffective assistance of counsel based on failure to request the Act III evaluation, but pursued his claim of ineffective assistance of counsel based on a failure to request a mitigation evaluation. Then in his federal habeas petition, Nooner asserted five independent claims of ineffective assistance of counsel including failure to secure a mitigation evaluation. The district court held that, except for the failure to secure a mitigation evaluation, Nooner had procedurally defaulted on all of his ineffective assistance of counsel claims. Nooner now appeals only that portion of *812his ineffective assistance claim related to the mitigation evaluation. I agree with the district court that Nooner procedurally defaulted on all of his ineffective assistance claims except for the one based on mitigation evaluation.12
“An ineffective assistance claim has two components: A petitioner must show that counsel’s performance was deficient, and that the deficiency prejudiced the defense.” Wiggins v. Smith, 539 U.S. 510, 521, 123 S.Ct. 2527, 156 L.Ed.2d 471 (2003). To establish deficient performance, a petitioner must demonstrate that counsel’s representation “fell below an objective standard of reasonableness.” Strickland v. Washington, 466 U.S. 668, 688, 104 S.Ct. 2052, 80 L.Ed.2d 674 (1984). In order to establish prejudice, “[t]he defendant must show that there is a reasonable probability that, but for counsel’s unprofessional errors, the result of the proceeding would have been different. A reasonable probability is a probability sufficient to undermine the confidence in the outcome.” Id. at 694, 104 S.Ct. 2052.
Deficient Performance.
In evaluating whether counsels’ performance fell below an objective standard of reasonableness, it is necessary to first identify the relevant professional standard of care. While Strickland counsels that no particular set of rules can satisfactorily govern the myriad of unique circumstances facing defense counsel, “[prevailing norms of practice as reflected in the American Bar Association standards and the like ... are guides to determining what is reasonable ....’’Id. at 688, 104 S.Ct. 2052. The Guidelines for the Appointment and Performance of Counsel in Death Penalty Cases (February 1989) (“Guidelines”) state that “[cjounsel should conduct independent investigations relating to the guilt/innocence phase and to the penalty phase of a capital trial. Both investigations should begin immediately ... and should be pursued expeditiously.” Guideline 11.4.1 at A. The Guidelines further explain that when selecting witnesses or evidence to present at sentencing,
counsel should consider the following: 1) Witnesses familiar with and evidence relating to the client’s life and development, from birth to the time of sentencing, who would be favorable to the client, explicative of the offense(s) for which the client is being sentenced, or would contravene evidence presented by the prosecutor; 2) Expert witnesses to provide medical, psychological, sociological or other explanations for the offense(s) for which the client is being sentenced ....
Guideline 11.8.3 at F. (emphasis added).
Attorneys representing clients who face the death penalty are specifically advised to consider all reasonably available evidence, including expert testimony.
Counsel should present to the sentencing entity or entities all reasonably available evidence in mitigation unless there are strong strategic reasons to *813forego some portion of such evidence. Among the topics counsel should consider presenting are: 1) Medical history (including mental and physical illness or injury, alcohol and drug use, birth trauma and developmental delays); 2) Educational history (including achievement, performance and behavior), special educational needs (including cognitive limitations and learning disabilities) and opportunity or lack thereof; ... 5) Family, and social history (including physical, sexual or emotional abuse, neighborhood surroundings and peer influence); and other cultural or religion [sic] influence, professional intervention (by medical personnel, social workers ...) or lack thereof; prior correctional experience (including conduct on supervision and in institutions, education or training, and clinical services); ... 8) Expert testimony concerning any of the above and the resulting impact on the client, relating to the offense and to the client’s potential at the time of sentencing.
Guideline 11.8.6 at A. and B. (emphasis added). With the appropriate professional standards of care established, I turn to the performance of Nooner’s two attorneys at trial.
In preparation for trial, defense counsel engaged an investigator who interviewed Nooner’s mother about his history. These conversations revealed that, during Noon-er’s early teenage years, he was placed in foster care after his mother was charged with child abuse and placed in two separate psychiatric institutions for severe emotional and behavioral problems. This preliminary investigation also revealed that Nooner experienced substance abuse problems. Trial counsel obtained records from Rivendell which indicated that Noon-er was under socialized, and experienced “considerable family dysfunction, as evidenced by multiple family conflicts.” Abstract of Exhibits to Rule 37 Hearing at 248 (Nooner’s brief to the Arkansas Supreme Court) (the “Rivendell Report”). The Rivendell Report further identified that his reading skills were four years behind placement, his math and written skills were five years behind placement, his knowledge was three years behind placement, and even though he was fourteen years old, his education level was that of a third grader. Id. at 249. This report concluded that Nooner’s behavioral problems were not caused by psychosis. Trial counsel terminated their investigation without obtaining school records, medical records, or records from child protection services. Trial counsel did not contact Nooner’s treating psychiatrists or request any type of sociological or psychiatric expert to assist them in developing or presenting a mitigation case.
Considering that Nooner faced the death penalty, developing this line of mitigating evidence was his best, and perhaps only, possibility of avoiding death. While the decision not to challenge Nooner’s competency to stand trial appears sound, I take issue with his attorneys’ decision not to secure a psychiatric expert to evaluate Nooner for purposes of developing mitigating evidence. The Guidelines advise defense counsel to “present to the sentencing entity or entities all reasonably available evidence in mitigation unless there are strong strategic reasons to forego some portion of such evidence.” Guideline 11.8.6 at A. The Guidelines further advise trial counsel to consider “[ejxpert testimony concerning any [mitigating evidence] and the resulting impact on the client, relating to the offense and to the client’s potential at the time of sentencing.” Id.
One of Nooner’s attorneys testified at the Rule 37 post-conviction hearing that the introduction of the Rivendell Report would not help Nooner’s case and that its *814contents foreclosed the need for further psychiatric investigation. Testimony of Ms. Lea Ellen Fowler, Rule 37 Hearing Transcript at 25-26. Trial counsels’ characterization at the Rule 37 hearing of their potential mitigation case suggests they discounted too quickly potential mitigating evidence. In contrast to Ms. Fowler’s testimony at the Rule 37 hearing, the record shows that Nooner was indeed from a broken home: by the age of fourteen, he had been removed from his home by the state, had been transferred from foster home to foster home, and subsequently institutionalized for several months at Ri-vendell. Additionally, in contrast to Ms. Fowler’s testimony, the record shows that Nooner did indeed suffer from substance abuse.
The information available to Nooner’s trial counsel indicated significant childhood disturbances that merited further investigation. While the Rivendell Report may have reasonably foreclosed psychosis itself as a mitigating circumstance, it did not foreclose an investigation into reasons for Nooner’s multiple foster home placements, investigation into his low educational achievements, or an investigation into his substance abuse. Most importantly, it did not foreclose the potential value of engaging a psychiatric expert to evaluate Noon-er and to explain to the jury the resulting impact these experiences had on Nooner. See Guideline 11.8.6 at B(8).
“[Cjounsel has a duty to make reasonable investigations or to make a reasonable decision that makes particular investigations unnecessary.” Strickland, 466 U.S. at 691, 104 S.Ct. 2052. “[S]trategic choices made after less than complete investigation are reasonable precisely to the extent that reasonable professional judgments support the limitations on investigation.” Id. Nooner’s trial counsels’ “strategic” decision not to pursue expert psychiatric assistance for the penalty phase was simply premature based on the initial information available to counsel. Under the facts of this case, I conclude that this failure to request a psychiatric expert to examine Nooner for the purpose of developing and presenting mitigating evidence constituted ineffective assistance of counsel under the Sixth Amendment.13
Prejudice.
In addition to deficient performance, Nooner must also establish prejudice to obtain relief. “In assessing prejudice, we reweigh the evidence in aggravation against the totality of available mitigating evidence.” Wiggins, 539 U.S. at 534, 123 S.Ct. 2527. Because Arkansas required juror unanimity to impose the death sentence, trial counsel only had to persuade one juror that there was a reasonable doubt whether the aggravating factors outweighed the mitigating factors, persuade a single juror that Nooner deserved mercy, or persuade a single juror to spare his life. See ARK. Code Ann. § 5-4-603 (1987).
Although Nooner’s stepfather testified during the penalty phase about Nooner’s troubled childhood and, to a limited extent, about his behavioral and emotional problems, without the testimony from a psychiatric expert, “the jurors were left with no guidance concerning how they might take such facts into consideration in mitigation of punishment.” Stephens v. Kemp, 846 *815F.2d 642, 655 (11th Cir.1988). The fact that no one other than Nooner’s obviously biased stepfather presented this mitigating evidence “diminished the impact on the jury of the facts [he] described.”14 Id. at 654. A psychiatric expert could have provided invaluable corroborating evidence strengthening the stepfather’s emotional testimony. I conclude that, given the scope and nature of Nooner’s troubled childhood, a psychiatric expert could have developed and presented potentially powerful mitigating evidence.
As the record stands, we lack enough information to determine whether the psychiatric evidence would have changed the verdict of death. No lower court has conducted any meaningful assessment of this evidence. I would therefore remand this case to the district court for a plenary hearing to evaluate Nooner’s expert psychiatric evidence to make this determination of prejudice in the first instance.
While Nooner may have been prejudiced by ineffective assistance of counsel during the penalty phase of his trial, prior to issuing relief it is also necessary to find that the adjudication of Nooner’s claim by the Arkansas Supreme Court “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). “[A] state-court decision involves an unreasonable application of [Supreme Court] precedent if the state court identifies the correct governing legal rule from [Supreme Court] cases but unreasonably applies it to the facts of the particular state prisoner’s case.” Williams v. Taylor, 529 U.S. 362, 407, 120 S.Ct. 1495, 146 L.Ed.2d 389 (2000).
The Arkansas Supreme Court resolved Nooner’s claim as follows:
Nooner alleges ineffective assistance of counsel because defense counsel did not request a mental evaluation as allowed under Ark. Code Ann. § 5-2-309. Nooner contends the results could have produced evidence that may have gone toward establishing some mitigating circumstance in sentencing. He argues that his counsel’s failure to request an evaluation prevented the judge and jury from having critical evidence showing a limited capacity. Competency to stand trial has not been raised as an issue. Nooner’s counsel did not request a mental evaluation. At the hearing below, Nooner’s trial counsel testified that they saw no reason for an evaluation at the time of trial. They reported that Noon-er involved himself intimately in his defense. He did legal research, participated in strategy discussions, and was articulate and able to convey his concerns and wishes. They also reported that Nooner behaved significantly different in the Rule 37 hearing than he did during his trial. Nooner offered testimony from his mother [15] that he had behavioral problems and emotional problems which they had shared with his trial counsel. However, she acknowledged that although he had been *816treated at Rivendale [sic], he had not been treated at a psychiatric facility nor prescribed anti-psychotic medication.
Onr review of the record indicates that the trial court thoroughly evaluated Nooner’s claim and reasonably believed the testimony of trial counsel that they carefully considered whether to request an evaluation but discerned no good-faith basis for doing so. Nooner’s trial counsel also presented evidence that they' had adduced evidence of Nooner’s troubled past and treatment through his stepfather during the penalty phase of his trial. We hold Nooner has not established that trial counsel’s decision not to request a psychiatric evaluation constituted ineffective assistance.
Nooner v. State, 339 Ark. 253, 4 S.W.3d 497, 500 (1999) (emphasis added). Although the Arkansas Supreme Court identified the correct Supreme Court precedent under Strickland, it performed an unreasonable application of the governing legal rules to the facts of the case.
First, the Arkansas Supreme Court incorrectly characterized Nooner’s claim as one of competency to stand trial, when in fact Nooner’s claim was about failure to investigate and present mitigating evidence. On appeal to that court, Nooner was not attempting to resurrect the competency issue, he was claiming “ineffective assistance of counsel as a result of the failure to seek psychiatric testimony for the penalty phase and to present the evidence thereon.” Abstract and Brief for Appellant at 356 (Nooner’s appellate brief before the Arkansas Supreme Court). However, when reviewing Nooner’s ineffective assistance claim, the Arkansas Supreme Court interjected issues only relevant to the competency issue which was not appealed. For example, the Arkansas Supreme Court’s opinion, supra, states that Nooner’s claim is based on a failure to “request a mental evaluation as allowed under Ark.Code Ann. § 5-2-309.” Noon-er, 4 S.W.3d at 500. However, this cited statute is specific to “Determination of fitness to proceed.” See ArkCode Ann. § 5-2-309 (1987). Furthermore, the Arkansas Supreme Court’s discussion of Nooner’s behavior at his trial and at the post-conviction hearing in state court (as a valid reason for not requesting an evaluation) demonstrates that the issue of competency to stand trial was conflated with the issue of a mitigation evaluation.
Second, the Arkansas Supreme Court’s conflation of the distinct claims of competency to stand trial with mitigation at sentencing caused that court to apply the wrong standard of care in evaluating defense counsels’ professional conduct. The Arkansas Supreme Court identified the statutory authority which governs competency to stand trial, see auk. Code Ann. § 5-2-309 (1987), and then applied the corresponding “good faith” basis professional standard from the ABA Criminal Justice Mental Health Standards16 to evaluate trial counsels’ performance. However, the good faith standard from the ABA Criminal Justice Mental Health Standards does not apply to conduct during the penalty phase of capital cases. The standard that should have been applied appears in The Guidelines for the Appointment and Per*817formance of Counsel in Death Penalty Cases (February 1989). No United States Supreme Court case holds, or even suggests, that a good faith basis to question the defendant’s competency to stand trial is required prior to investigating or presenting psychologically-based mitigating evidence.
The application of the wrong standard meant that the Arkansas Supreme Court failed to evaluate Nooner’s trial counsels’ performance for reasonableness under prevailing professional norms of practice. Strickland, 466 U.S. at 688, 104 S.Ct. 2052. This was an objectively unreasonable application of clearly established Supreme Court precedent. 28 U.S.C. § 2254(d).
I would hold that Nooner’s allegation of ineffective assistance of counsel is sufficient to require a federal district court to evaluate the expert psychiatric evidence and determine whether a new trial before a jury on the penalty phase of Nooner’s trial should be held.
. The defaulted claim of ineffective assistance based on the attorneys’ failure to fully investigate Nooner’s troubled childhood may share a factual background with the claim of ineffective counsel based on a failure to secure a psychiatric expert to present mitigating evidence at the penalty phase. For instance, at a new sentencing hearing, a psychiatric expert might delve into Nooner’s troubled childhood and testify about those experiences in an attempt to mitigate the sentence. Such testimony would be wholly appropriate. A psychiatric expert should not be prevented from testifying about Nooner's troubled childhood and dysfunctional social behavior if the psychiatric expert determined they were relevant for the purpose of presenting mitigating psychiatric evidence. This is a death penalty case and Nooner is entitled to every benefit of a reasonable doubt.
. I do not suggest that trial counsel had a duty to present such testimony if, after adequate investigation, it appeared that it would be harmful to Nooner's mitigation case. I simply conclude that failure to pursue such evidence, based on the information available to them at the time, was unreasonable under the circumstances. Wiggins v. Smith, 539 U.S. 510, 523-24, 123 S.Ct. 2527, 156 L.Ed.2d 471 (2003); Pickens v. Lockhart, 714 F.2d 1455, 1466-67 (8th Cir.1983).
. During the guilt phase, Nooner’s stepfather (Mr. Hendricks) testified as Nooner’s alibi witness that Nooner was home at the time of the murder. Considering the jury convicted Nooner, they obviously found Mr. Hendricks’ testimony less than credible. Nonetheless, Nooner’s attorneys put the same discredited witness on the stand as the sole witness presenting mitigating evidence. Nooner's mother was unable to testify at trial. Apparently, her doctor considered the emotional stress too great and advised her not to testify.
. This testimony occurred after the trial in the Rule 37 post-conviction proceeding in the state district court.
. The relevant guideline states:
In the absence of good faith doubt that the defendant is competent to stand trial it is improper for either party to move for evaluation. It is improper for either party to use the incompetence process for purposes unrelated to incompetence to stand trial such as to obtain information for mitigation of sentence, to obtain favorable plea negotiation, or to delay the proceedings against the defendant.
ABA Criminal Justice Mental Health Standard 7-4.2(e) (1989) (emphasis added).