2022 IL 127824
IN THE
SUPREME COURT
OF
THE STATE OF ILLINOIS
(Docket No. 127824)
THE PEOPLE OF THE STATE OF ILLINOIS, Appellee, v.
LAURA A. EPSTEIN, Appellant.
Opinion filed November 28, 2022.
JUSTICE CARTER delivered the judgment of the court, with opinion.
Chief Justice Theis and Justices Anne M. Burke, Neville, Michael J. Burke,
Overstreet, and Holder White concurred in the judgment and opinion.
OPINION
¶1 In this case, the circuit court of Boone County granted the defendant’s pretrial
motion to exclude the result of her blood-alcohol concentration (BAC) test from
blood drawn four hours after a traffic stop. The circuit court held that the test was
inadmissible under Illinois Rule of Evidence 403 (eff. Jan. 1, 2011) because its
probative value was substantially outweighed by the risk of unfair prejudice given
the facts of this case. The appellate court reversed the trial court’s judgment and
remanded for further proceedings. For the following reasons, we affirm the
appellate court’s judgment and remand.
¶2 I. BACKGROUND
¶3 Defendant Laura A. Epstein was charged with three counts of aggravated
driving under the influence. Count I alleged that defendant committed the offense
by driving under the influence of alcohol while transporting a person under 16 years
of age and having previously committed the offense of DUI (625 ILCS 5/11-
501(d)(1)(K) (West 2016)). Count II alleged that defendant drove with a BAC of
0.08 or more while transporting a person under 16 years of age and having
previously committed the offense of DUI. Id. Count III alleged defendant drove
with any amount of a drug, substance, or compound or combination thereof in her
breath or blood while transporting a person under 16 years of age and having
previously committed the offense of DUI. Id.
¶4 Defendant filed a pretrial motion to exclude her BAC test result of 0.107
obtained from blood drawn pursuant to a search warrant approximately four hours
after the traffic stop. Defendant contended, in pertinent part, that the prejudicial
effect of admitting the BAC test result would substantially outweigh any probative
value because retrograde extrapolation could not be performed to establish her BAC
at the time of driving. Thus, defendant sought an order excluding the evidence
under Illinois Rule of Evidence 403 (eff. Jan. 1, 2011).
¶5 At the hearing on the motion, defendant offered the testimony of Dr. James
O’Donnell, an expert in the field of pharmacology and the effects of alcohol on the
human body. Dr. O’Donnell testified that he had performed retrograde
extrapolation calculations many times and described it as a method of using a
known BAC to determine the person’s BAC level at an earlier point in time.
¶6 Dr. O’Donnell interviewed defendant and reviewed the traffic stop video, video
of the field sobriety tests, and video of defendant sitting in the back seat of the
squad car. Based on that information and the available facts of this case, Dr.
O’Donnell testified that retrograde extrapolation could not be performed to
determine defendant’s BAC at the time of driving because the time when
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defendant’s alcohol absorption peaked, and elimination began, could not be
determined. Retrograde extrapolation could be performed only if defendant’s
alcohol absorption had peaked prior to the traffic stop.
¶7 Dr. O’Donnell explained that “drinking occurred during the hour before the
traffic stop” and alcohol was “being absorbed at the time of the traffic stop.”
Defendant was stopped at approximately 10 p.m., arrested at approximately 10:30
p.m., and had her blood drawn between 2 and 2:30 the next morning. Based on
when defendant stated she last consumed alcohol and how she acted in the police
videos, Dr. O’Donnell opined that defendant’s alcohol absorption was not complete
at the time of the traffic stop. Dr. O’Donnell testified that, when defendant was
stopped at 10 p.m., she stood and walked without losing her balance and her speech
was not slurred. At 10:30 p.m., however, defendant exhibited “obvious
manifestations of intoxication,” including slurred speech and altered balance.
¶8 Based on defendant’s statement to him and his observations, Dr. O’Donnell
opined that defendant was still absorbing alcohol following the traffic stop and that
her peak absorption occurred sometime after 10:20 p.m. The information available
was not sufficient to perform retrograde extrapolation because it was not possible
to determine when defendant’s alcohol absorption peaked. Thus, he concluded that
the BAC test result only proved that defendant consumed alcohol before driving,
but there was no way to determine her BAC at the time of driving.
¶9 The State did not present any evidence. The trial court found that the BAC test
result was probative but, because retrograde extrapolation would be inherently
unreliable in this case, its probative value was substantially outweighed by its
prejudicial effect. The trial court, therefore, granted defendant’s motion to exclude
the evidence.
¶ 10 On appeal, the parties continued to dispute whether the evidence was admissible
under Illinois Rule of Evidence 403 (eff. Jan. 1, 2011). 2021 IL App (2d) 191059-
U, ¶ 19. Under Rule 403, relevant evidence may be excluded if its probative value
is substantially outweighed by the risk of unfair prejudice or confusion of the issues
or the potential for misleading the jury. Id. ¶ 28. A trial court’s decision under Rule
403 is reviewed for abuse of discretion. Id.
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¶ 11 Here, the test result was probative of defendant’s BAC when she was driving.
Id. ¶ 29. Although the appellate court was “troubled by the four-hour delay” in
obtaining and testing defendant’s blood (id. ¶ 30), case law demonstrates that the
passage of time goes to the weight given to the result, not its admissibility (id. ¶ 29
(citing People v. Torruella, 2015 IL App (2d) 141001, ¶ 42, Village of Bull Valley
v. Winterpacht, 2012 IL App (2d) 101192, ¶¶ 13, 15, People v. Zator, 209 Ill. App.
3d 322, 332 (1991), and People v. Call, 176 Ill. App. 3d 571, 579 (1988)). The
appellate court concluded that the trial court erred in finding the probative value of
the BAC test result was substantially outweighed by the danger of unfair prejudice.
Id. ¶ 31. Accordingly, the appellate court reversed the trial court’s judgment and
remanded for further proceedings. Id. ¶ 33.
¶ 12 Justice McLaren dissented, asserting that the trial court properly exercised its
discretion in excluding the evidence. Id. ¶ 41 (McLaren, J., dissenting). Expert
testimony established that the test results were unreliable to determine defendant’s
BAC at the time of driving. Id. Justice McLaren concluded that the introduction of
the BAC test result, with no possibility of explanation or context, would clearly
result in unfair prejudice, confusion, and misdirection. Id. ¶ 43. He, therefore,
would have held that the trial court did not abuse its discretion in excluding the
BAC test result. Id.
¶ 13 We allowed defendant’s petition for leave to appeal. Ill. S. Ct. R. 315 (eff. Oct.
1, 2021).
¶ 14 II. ANALYSIS
¶ 15 On appeal to this court, defendant contends that the trial court properly
exercised its discretion in excluding the BAC test result. The probative value of the
test result is outweighed by its risk of unfair prejudice because an expert witness
testified that the result is inherently unreliable to determine defendant’s BAC at the
time of driving. The unreliable test result is offered to prove an element of the
criminal offense, essentially establishing a mandatory irrebuttable presumption and
shifting the burden of persuasion and proof from the State to defendant.
¶ 16 Defendant contends that, based on unreliable evidence, the jury will be allowed
to assume that she drove with a BAC over 0.08. The expert witness determined,
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however, that the result was useless in assessing defendant’s BAC at the time of
driving. Defendant maintains that the trial court did not abuse its discretion in
excluding the evidence under Rule 403 given the substantial risk of unfair prejudice
from presenting the jury with an inherently unreliable BAC test result.
¶ 17 The State responds that defendant’s BAC test result is highly probative to show
that she had been drinking before she got into the car, that she was intoxicated when
she was pulled over, and that her BAC was over 0.08 when she was driving. The
evidence is not unfairly prejudicial and does not tend to suggest the decision should
be made on an improper or emotional basis. Defendant’s BAC is probative only of
the question at issue here, whether she consumed alcohol to the point that she was
intoxicated while driving.
¶ 18 The State further observes that whether defendant’s postarrest BAC is
indicative of her BAC while driving depends on if the evidence shows she only
drank immediately before driving and that she grew increasingly intoxicated after
the traffic stop. Dr. O’Donnell based his opinion on defendant’s statement to him
that she only drank immediately before driving and on his review of the traffic stop
videos, but the factfinder may reach its own conclusions on those points after
reviewing the evidence presented at trial. The factual basis for Dr. O’Donnell’s
opinion would be undermined if the factfinder determined that defendant did not
grow increasingly intoxicated during the traffic stop. In that case, the factfinder
could conclude that defendant was no longer absorbing alcohol after she was
stopped, and there would be no question that her postarrest BAC of 0.107 showed
her BAC while driving was far above the legal limit.
¶ 19 The State argues that the underlying facts should be determined by the
factfinder. Permitting suppression of evidence based on defendant’s own self-
serving statements would allow her to avoid liability simply by telling her expert
witness that she only consumed alcohol immediately prior to driving. The State,
therefore, concludes that the trial court abused its discretion in excluding the
evidence under Rule 403.
¶ 20 Generally, evidence is relevant and admissible if it has “any tendency to make
the existence of any fact that is of consequence to the determination of the action
more probable or less probable than it would be without the evidence.” Ill. R. Evid.
401 (eff. Jan. 1, 2011); see also Ill. R. Evid. 402 (eff. Jan. 1, 2011). “Although
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relevant, evidence may be excluded if its probative value is substantially
outweighed by the danger of unfair prejudice, confusion of the issues, or misleading
the jury, or by considerations of undue delay, waste of time, or needless
presentation of cumulative evidence.” Ill. R. Evid. 403 (eff. Jan. 1, 2011). The trial
court’s decision on whether to admit evidence is reviewed for abuse of discretion.
People v. King, 2020 IL 123926, ¶ 35.
¶ 21 The function of a jury is “ ‘to assess the credibility of witnesses, weigh the
evidence presented, resolve conflicts in the evidence, and draw reasonable
inferences from the evidence.’ ” People v. Ward, 2011 IL 108690, ¶ 34 (quoting
People v. Moss, 205 Ill. 2d 139, 164 (2001)). To perform its function properly, the
jury must be given as much relevant, admissible evidence as possible. Id. Without
that evidence, the reliability of the jury’s verdict may be called into question. Id.
¶ 22 Accordingly, the plain language of Rule 403 favors admission of relevant
evidence. Under the rule, relevant evidence may not be excluded simply because
its probative value is outweighed by its prejudicial effect. Rather, by its plain terms,
Rule 403 provides for exclusion of relevant evidence only if its probative value is
substantially outweighed by the risk of unfair prejudice. Ill. R. Evid. 403 (eff. Jan.
1, 2011). The jury is, therefore, placed in its proper position of considering relevant
evidence and assigning it the appropriate weight.
¶ 23 In this case, the BAC test result is certainly relevant to the issues. The result, at
a minimum, shows defendant consumed alcohol before driving. Indeed, the test
result of 0.107, measured from blood drawn approximately four hours after driving,
may indicate that defendant consumed a significant amount of alcohol before
driving that night. That is relevant to whether she was under the influence of alcohol
while driving. The BAC test result is highly probative here regardless of whether
retrograde extrapolation may be performed to calculate defendant’s BAC while
driving.
¶ 24 Defendant, however, contends that the evidence must be excluded as unfairly
prejudicial. Defendant’s core argument is that the jury will be misled to believe the
BAC test result is conclusive proof that she was driving with a BAC over 0.08 when
defendant’s expert witness testified that the result is inherently unreliable to
establish that proposition. The alleged prejudicial impact of the BAC test result is,
therefore, based primarily on a potential misuse of the evidence to mislead the jury.
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¶ 25 Initially, defendant’s argument appears to assume that the BAC test result is
admissible only if retrograde extrapolation is performed to establish her BAC while
driving. The State, however, is generally not required to provide expert testimony
on retrograde extrapolation when a BAC test result is above the statutory limit. See
Winterpacht, 2012 IL App (2d) 101192, ¶ 13 (holding that, when a BAC test result
is above the statutory limit and “a reasonable amount of time elapses between when
the defendant was driving and the test, extrapolation evidence is permissible but is
not a foundational requirement”); Torruella, 2015 IL App (2d) 141001, ¶¶ 41-42
(same). Our appellate court has long held that matters of delay between driving and
BAC testing go to the weight of the evidence and must be viewed in light of the
surrounding circumstances. People v. Newman, 163 Ill. App. 3d 865, 868 (1987)
(citing People v. Kappas, 120 Ill. App. 3d 123, 128-29 (1983)). Given the facts of
a particular case, the jury may reasonably infer that a defendant’s BAC at the time
of driving was “similar to, if not higher than,” the level when it was subsequently
tested. Winterpacht, 2012 IL App (2d) 101192, ¶ 15. Defendant has submitted
expert witness testimony challenging the reliability of the BAC test result to
establish her BAC at the time of driving, but that testimony generally goes to the
weight of the evidence, not its admissibility.
¶ 26 Contrary to defendant’s argument, the risk of unfair prejudice in misleading the
jury will be remote if the jury is allowed to consider all the evidence on the BAC
test result and assign it the appropriate weight. In this case, the trial court excluded
the BAC test result based entirely on the testimony of defendant’s expert witness
that the result was “inherently unreliable” to determine defendant’s BAC at the time
of driving. The expert’s opinion, in turn, was based on his determination of the
underlying facts, namely, his acceptance of defendant’s statement that she
consumed alcohol immediately before driving and his conclusion from viewing the
traffic stop video recordings that defendant became more intoxicated during the
traffic stop. Of course, as the State argues, if those underlying factual
determinations are not accepted, the expert’s opinion testimony is undermined. If
the factfinder discounts as self-serving defendant’s statement that she drank
immediately before driving and concludes that the video recordings do not establish
that she became increasingly intoxicated during the traffic stop, then the expert’s
opinion based on those facts becomes unsupported.
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¶ 27 Based on its determinations of fact, the factfinder could conclude that
defendant’s alcohol absorption peaked before the traffic stop. The BAC test result
from blood drawn after the traffic stop would then be indicative of defendant’s BAC
while driving. Defendant’s expert acknowledged that, if defendant’s alcohol
absorption had peaked prior to the traffic stop, retrograde extrapolation could be
used to determine defendant’s BAC at the time of the stop.
¶ 28 In sum, Dr. O’Donnell’s expert opinion, that the BAC test result is unreliable
to show defendant’s BAC at the time of driving, is based on defendant’s statement
to him that she drank immediately before driving and his perception from the video
recordings that she continued to become more intoxicated as the stop progressed.
Dr. O’Donnell’s view of defendant’s intoxication during the traffic stop was
premised largely on his observations that her balance became unsteady and her
speech became slurred. The credibility of defendant’s statement on her alcohol
consumption and the conclusions after observing the video recordings are factual
determinations that may be questioned by the jury. If those underlying factual
determinations are not accepted by the jury, the BAC test result may be used to
establish defendant’s BAC level at the time of driving.
¶ 29 Ultimately, the factfinder should be allowed to weigh the evidence given all the
factors in this case. Defendant may certainly present evidence at trial, including Dr.
O’Donnell’s testimony, to show the potential problems with the BAC test result,
and she may argue that the test result is inherently unreliable to establish her BAC
at the time of driving. The factfinder may determine that the underlying facts
support the expert’s findings that defendant consumed alcohol immediately before
driving and that her alcohol absorption did not peak until after driving. In that case,
the jury may credit the expert’s opinion that the test result is inherently unreliable
to prove defendant’s BAC while driving.
¶ 30 The critical point, however, is that the factfinder should weigh all of these
questions of fact and make the credibility determinations required to assign the
appropriate weight to the evidence and testimony. The BAC test result will not pose
a substantial risk of misleading the jury if the jury is allowed to hear the evidence
and make its own determinations of the underlying facts used to formulate the
expert’s opinion on that evidence. Given the specific facts of this case, we conclude
that the probative value of the BAC test result is not “substantially outweighed by
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the danger of unfair prejudice, confusion of the issues, or misleading the jury, or by
considerations of undue delay, waste of time, or needless presentation of
cumulative evidence.” Ill. R. Evid. 403 (eff. Jan. 1, 2011).
¶ 31 We also necessarily reject defendant’s related argument that admission of the
BAC test result will violate her constitutional right to due process. Defendant
contends that admission of the evidence creates an unconstitutional mandatory
presumption that she drove with a BAC of 0.08 or more. According to defendant,
the appellate court’s decision allows admission of unreliable evidence to
conclusively prove an element of a criminal offense.
¶ 32 Due process requires the State to prove every element of a criminal offense
beyond a reasonable doubt, but the State may rely on certain presumptions in
proving those elements. People v. Pomykala, 203 Ill. 2d 198, 203 (2003). A
permissive presumption allows, but does not require, the trier of fact to infer the
existence of the ultimate fact upon proof of the predicate fact. Id. The trier of fact
is free to accept or reject a permissive presumption. People v. Watts, 181 Ill. 2d
133, 142 (1998). Mandatory presumptions, on the other hand, require the factfinder
to accept the presumption, and they are per se unconstitutional under Illinois law.
Pomykala, 203 Ill. 2d at 203-04.
¶ 33 The admission of the BAC test result in this case does not create a mandatory
presumption. The State still has the burden of proving the elements of the offenses.
The BAC test result is not irrebuttable, and the factfinder is not required to accept
it. Defendant may submit evidence, including the testimony of Dr. O’Donnell, to
show that the BAC test result is unreliable to establish her BAC at the time of
driving. Based on the evidence of its reliability, the factfinder may accept or reject
the BAC test result for the purpose of showing defendant’s BAC at the time of
driving. Thus, the admission of the test result does not violate defendant’s right to
due process. It simply allows the jury to perform its essential function of weighing
and assigning the appropriate weight to all relevant evidence.
¶ 34 In sum, we hold that the trial court abused its discretion in excluding the
evidence in this case under Rule 403. Accordingly, the appellate court’s judgment
is affirmed.
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¶ 35 III. CONCLUSION
¶ 36 For the reasons stated above, we affirm the appellate court’s judgment and
remand to the trial court for further proceedings.
¶ 37 Appellate court judgment affirmed.
¶ 38 Circuit court judgment reversed.
¶ 39 Cause remanded.
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