Scott McLaughlin v. Anne L. Precythe

United States Court of Appeals
For the Eighth Circuit
___________________________
No. 18-3510
___________________________
Scott McLaughlin
Petitioner - Appellee
v.
Anne L. Precythe
Respondent - Appellant
____________
Appeal from United States District Court
for the Eastern District of Missouri - St. Louis
____________
Submitted: March 17, 2021
Filed: August 18, 2021
____________
Before SHEPHERD, ERICKSON, and KOBES, Circuit Judges.
____________
KOBES, Circuit Judge.
Scott McLaughlin filed this habeas action alleging (1) he received ineffective
assistance of sentencing counsel when his lawyer failed to investigate potential
impeachment evidence of his own expert witness; and (2) his death sentence was
unconstitutional due to flaws in the jury instructions. The district court agreed and
vacated his death sentence. We disagree and reverse.

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I.
A.
The night before a hearing on his adult abuse charge, Scott McLaughlin
ambushed his ex-girlfriend Beverly Guenther while she was leaving work. When
Guenther told him to leave, McLaughlin attacked, stabbing Guenther repeatedly with
a steak knife. Guenther fought for her life, scratching McLaughlin’s arms and face,
but he forced her to the ground and continued to stab and strangle her. Then he raped
her. Once he was finished, McLaughlin threw Guenther’s body into the back seat
of his car and took her to the Missouri River to dispose of her remains. He couldn’t
dump her into the river because the brush was too thick. Instead, he left Guenther’s
half-naked body in the brush and drove off.
The next day, McLaughlin was “laugh[ing] and jok[ing].” App. 2336. A
friend described his demeanor as “friendly” and said that the two had “nice
conversations.” Id. He went shopping to buy bleach and other cleaning supplies,
which he said he needed to get rid of a mildew smell in his car. When he got home
from shopping, McLaughlin poured the bleach inside his car.
Police came looking for McLaughlin and brought him in for questioning.
They found blood on his clothes and in his car. At the station, police showed him
the evidence they had against him, and McLaughlin eventually confessed and led
police to Guenther’s body.
The State charged McLaughlin with rape, first-degree murder, and two counts
of armed criminal action and sought the death penalty. A jury convicted him of rape,
first-degree murder, and one count of armed criminal action.

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B.
The case moved to the penalty phase. In Missouri, when the State seeks a
penalty of death after a jury conviction of first-degree murder, “a second stage of the
trial shall proceed at which the only issue shall be the punishment to be assessed and
declared.” Mo. Ann. Stat. § 565.030.4. The trier of fact hears evidence in
aggravation and mitigation of the punishment. Id. After that, the jury must find
beyond a reasonable doubt that a statutory aggravator is present. Id. § 565.030.4(2).
If no aggravator is present, then death cannot be assessed. Id. If the jury finds a
statutory aggravator, they move to the second step where they consider whether the
evidence in mitigation is sufficient to outweigh the evidence in aggravation. Id.
§ 565.030.4(3). If the jury finds it is, then death cannot be assessed. Id. If the
mitigation evidence does not outweigh the aggravation evidence, then the jury
proceeds to the third step to “decide[] under all of the circumstances” whether or
“not to assess and declare the punishment at death.” Id. § 565.030.4(4). If they
cannot, the judge must decide. Id. § 565.030.4.
The State argued four statutory aggravators: (1) the crime involved depravity
of mind based on the repeated and excessive acts of physical abuse McLaughlin
inflicted on Guenther; (2) the murder was committed while McLaughlin was
engaged in the perpetration of forcible rape; (3) Guenther was killed because she
was a potential witness in McLaughlin’s burglary prosecution; and (4) Guenther was
killed because she was a potential witness in an order-of-protection investigation.
In support, the State presented evidence of McLaughlin’s history of stalking,
harassment, and aggression towards Guenther. Following their break-up,
McLaughlin repeatedly called Guenther at work, showed up at her office uninvited,
and lurked outside of her home. Another time, police arrested McLaughlin for
burglarizing Guenther’s house. After charges were filed, McLaughlin stopped
Guenther in the parking lot of her work to ask about the pending case. When
Guenther told McLaughlin that she did not want to talk to him, he tried to kiss her
twice. On another occasion, McLaughlin jumped from the bushes and groped her

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breast. Guenther reported McLaughlin was becoming more violent and aggressive
as time went on.
The State also presented evidence of McLaughlin’s criminal history.
McLaughlin had been convicted for first-degree tampering, first-degree sexual
assault against a minor, forgery, and felony nonsupport. He was also convicted of
third-degree assault for attempting to cut Guenther’s neighbor with a knife.
McLaughlin argued for non-statutory mitigators in his defense. He started
with a discussion of his troubled childhood. McLaughlin’s biological father was an
alcoholic who abused his mother. He was placed in multiple foster homes.
Eventually, he was placed with and adopted by Louise and Harlan McLaughlin.
Harlan physically abused him. At a young age, McLaughlin was beaten with a
paddle, but, as time went on, Harlan, a police officer, used a Taser and nightstick to
punish him. McLaughlin also suffered emotional abuse. He and his siblings had
their access to food limited by locks placed on the refrigerator and cabinet doors.
McLaughlin’s sister also recounted that Louise once forced McLaughlin to drown a
kitten in a bucket of water.
Next, McLaughlin presented evidence from medical professionals. When
McLaughlin was nine, he underwent a comprehensive mental evaluation by two
doctors—Dr. Anthony Udziela and Dr. Pasquale Accardo. Both testified at the
penalty phase.
Dr. Udziela talked about McLaughlin’s intelligence. He noted that
McLaughlin has a low IQ and suffered from significant issues related to attachment,
anxiety, and mistrust associated with the neglect he suffered at a young age. He said
that McLaughlin’s childhood problems “markedly affected his development and had
a major impact on him resulting in an adjustment disorder with depressed features.”
App. 2482.

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Dr. Accardo testified about a neurodevelopmental assessment. The test
showed that McLaughlin’s language skills, common sense monitoring, and cognitive
ability were all deficient. Dr. Accardo also testified that McLaughlin’s attention
deficit hyperactive disorder and impulsivity were neurologically based. He further
said that while McLaughlin was capable of making good choices, these limitations
and McLaughlin’s childhood had an impact on his ability to do so. Dr. Accardo also
observed that McLaughlin appeared to be suffering from depression.
McLaughlin then called Dr. Sripatt Kulkamthorn, his treating physician
before the murder. Dr. Kulkamthorn testified that McLaughlin struggled with
depression and anxiety. Dr. Kulkamthorn prescribed McLaughlin an antidepressant,
but McLaughlin only received the pills during visits because he could not afford the
prescription.
Next, Dr. Mark Cunningham, a clinical and forensic psychologist, testified
about his examination of McLaughlin. Dr. Cunningham conducted interviews with
McLaughlin and several members of his biological and adoptive families and
reviewed McLaughlin’s medical, academic, mental health, and prison records. He
testified that McLaughlin had a choice when he killed Guenther, but that the choice
was affected by risk and protective factors that pervaded his life, arising from his
childhood and other factors.
At closing argument, McLaughlin’s lawyer urged the jury to consider the
“excessive” evidence in mitigation of McLaughlin’s moral culpability. App. 2589.
Counsel acknowledged that McLaughlin could understand the choice he made, but
argued that the choice was colored by the facts and circumstances of his life.
The jury could not decide the issue of death. In a special verdict form, the
jury found the existence of a statutory aggravator—depravity of mind—beyond a
reasonable doubt. The jurors did not find unanimously that the mitigating factors
outweighed the aggravating factors. Turning to the next step, the jury could not
unanimously agree on whether death was warranted under all of the circumstances.

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Because the jurors were unable to agree on punishment, adjudication of the issue
went to the trial judge. The judge sentenced McLaughlin to death.
McLaughlin appealed, and the Missouri Supreme Court affirmed his death
sentence. State v. McLaughlin, 265 S.W.3d 257 (Mo. 2008) (McLaughlin I). The
court found that the State’s process was consistent with Ring v. Arizona, 536 U.S.
584, 589 (2002), which held that “[c]apital defendants . . . are entitled to a jury
determination of any fact on which the legislature conditions an increase in their
maximum punishment,” because the jury had already found the facts necessary to
make McLaughlin eligible for a death sentence. McLaughlin I, 265 S.W.3d at 264.
C.
McLaughlin filed a state habeas petition alleging that his sentencing counsel
were constitutionally deficient because they failed to call a psychiatrist like Dr.
Stephen Peterson, whom McLaughlin proffered in support of his petition. If counsel
had done so, he claimed, the jury would have heard evidence about McLaughlin’s
mental state at the time he murdered Guenther. Specifically, he was under extreme
mental or emotional disturbance which substantially impaired his ability to
appreciate the criminality of his conduct. McLaughlin alleged that if the jury heard
testimony like this, it would have supported statutory mitigators and there is a
reasonable probability that he would not have been sentenced to death.
In fact, McLaughlin’s lawyers had such a witness—Dr. Keith Caruso—but
chose not to put him on the stand because of last-minute questions about his
background. Dr. Caruso would have testified that McLaughlin was under extreme
emotional disturbance and, due to mental illness, lacked the ability to appreciate the
criminality of his conduct. He would also have testified that McLaughlin was
suffering from a depressive episode of bipolar disorder at the time of the murder.
Dr. Caruso was hired on the recommendation of Lisa McCulloch, a mitigation
specialist. McCulloch saw Dr. Caruso give a presentation at a death penalty legal

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education program. David Kenyon, one of the members of McLaughlin’s trial team,
reviewed Dr. Caruso’s curriculum vitae and found he was licensed in several states
but did not do more research. Later, Robert Steele joined the trial team. Steele did
not inquire into Dr. Caruso’s background because he “had no reason to think there
was anything wrong with Dr. Caruso.” App. 2741.
During the jury’s deliberations at the guilt phase, Dr. Caruso told
McLaughlin’s lawyers about potential impeachment evidence that could be used
against him: seventeen years earlier he had falsified data in a lab report. The data
was never published, so no sanctions were imposed, but there was an investigation
and the information was published in the Federal Register. Dr. Caruso said that the
impeachment evidence had only been used in three of the ninety cases he testified
in, and he gave counsel a list of rehabilitation questions.
While Steele knew the information could be problematic, he still planned to
call Dr. Caruso. During opening arguments of the penalty stage, Steele said the jury
would hear from multiple experts, including Dr. Caruso. The defense team later
changed their mind. At the close of the penalty stage, Steele told the State and the
trial court about the decision not to call Dr. Caruso. He said he did not believe it
was ineffective to mention him in opening, but warned the prosecution not to
mention Dr. Caruso in closing argument. The prosecution argued that the defense
did not present testimony about McLaughlin’s state of mind at the time of the
murder, but did not specifically discuss the failure to call Dr. Caruso.
The motion court denied habeas relief and found that the decision to not call
Dr. Caruso was reasonable. The motion court also found that the failure to call a
psychiatrist like Dr. Peterson did not prejudice McLaughlin because Dr. Peterson’s
testimony was similar to the evidence of the other testifying experts.
The Missouri Supreme Court affirmed. See McLaughlin v. State, 378 S.W.3d
328, 334 (Mo. 2011) (McLaughlin II). On appeal, McLaughlin raised a new claim
that his counsel were also ineffective for failing to investigate Dr. Caruso’s

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background. Id. at 340. The court denied that claim on procedural grounds, finding
the argument was waived. Id.
D.
McLaughlin then filed this petition, including allegations that his sentencing
counsel were ineffective for failing to investigate Dr. Caruso’s credentials and that
his jury instructions violated Mills v. Maryland, 486 U.S. 367 (1988) and Ring.
After an evidentiary hearing, the district court vacated McLaughlin’s death
sentence. The court found that McLaughlin’s sentencing counsel were ineffective
in violation of his Sixth Amendment rights for failing to investigate Dr. Caruso’s
reliability as a witness. The district court found that this prejudiced McLaughlin
because the potential testimony of a psychiatrist like Dr. Peterson made for a
reasonable probability of a different sentencing outcome. This was because Dr.
Peterson examined McLaughlin in person and would have said that McLaughlin had
a reduced capacity to conform his conduct to the requirements of the law at the time
of the murder. That evidence would have been particularly relevant, the court found,
because the sentencing case was a close call, as evidenced by the jury’s deadlock on
the issue. More evidence may have moved the jury enough to change the outcome.
The court also found that McLaughlin’s sentencing procedure was
constitutionally deficient under Mills and Ring. As to the Mills claim, the court
found that requiring the jury to unanimously find that the mitigating factors
outweighed the aggravating factors was per se unconstitutional. On the Ring claim,
the court found that Missouri law treats the balancing stage as an issue of fact. As
an issue of fact, Ring would require a jury to unanimously find the mitigating factors
do not outweigh the aggravating factors. In reaching that conclusion, the district
court relied on the Missouri Supreme Court’s decision in State v. Whitfield, 107
S.W.3d 253 (Mo. 2003), abrogated by State v. Wood, 580 S.W.3d 566, 585 (Mo.
2019), reh’g denied (Sept. 3, 2019), cert. denied, 140 S. Ct. 2670 (2020).

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The State appealed.
II.
The State first argues that McLaughlin’s Sixth Amendment right to effective
assistance of counsel was not violated. “A district court’s decision in a habeas claim
of ineffective assistance of counsel presents a mixed question of fact and law.”
United States v. White, 341 F.3d 673, 677 (8th Cir. 2003). “We review the
ineffective assistance issue de novo, but findings of underlying predicate facts are
reviewed under the clearly erroneous standard.” Id.
“A convicted defendant’s claim that counsel’s assistance was so defective as
to require reversal of a conviction or death sentence has two components.”
Strickland v. Washington, 466 U.S. 668, 687 (1984). “First, the defendant must
show that counsel’s performance was deficient.” Id. “Second, the defendant must
show that the deficient performance prejudiced the defense.” Id. “Surmounting
Strickland’s high bar is never an easy task.” Padilla v. Kentucky, 559 U.S. 356, 371
(2010). The State argues that McLaughlin fails both prongs.
A.
McLaughlin claims his sentencing counsel were deficient for failing to
investigate Dr. Caruso’s credentials. While “strategic choices made after thorough
investigation of law and facts relevant to plausible options are virtually
unchallengeable,” “strategic choices made after less than complete investigation are
reasonable precisely to the extent that reasonable professional judgments support the
limitations on investigation.” Strickland, 466 U.S. at 690–91. “In other words,
counsel has a duty to make reasonable investigations or to make a reasonable
decision that makes particular investigations unnecessary.” Id. at 691.
“In assessing counsel’s investigation, we must conduct an objective review of
their performance, measured for ‘reasonableness under prevailing professional

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norms,’ which includes a context-dependent consideration of the challenged conduct
as seen ‘from counsel’s perspective at the time.’” Wiggins v. Smith, 539 U.S. 510,
523 (2003) (quoting Strickland, 466 U.S. at 688, 689). Counsel should be “strongly
presumed to have rendered adequate assistance and made all significant decisions in
the exercise of reasonable professional judgment.” Strickland, 466 U.S. at 690.
“The burden of rebutting this presumption rests squarely on the defendant.” Dunn
v. Reeves, 141 S. Ct. 2405, 2410 (2021) (citation omitted).
Before addressing this challenge, we carefully delineate what this case is (and
is not) about. McLaughlin takes issue with his counsel’s failure to find potential
impeachment evidence on Dr. Caruso. This issue is qualitatively different from the
one presented in many of the cases relied on by the district court, which concern the
failure to investigate a potential defense or inquire into the substance of the expert
witness’s testimony. A death penalty case involves mountains of evidence and many
witnesses. And “[d]efense lawyers have limited time and resources, and so must
choose from among countless strategic options.” Dunn, 141 S. Ct. at 2410 (citation
omitted). Finding impeachment evidence on a witness is no small task, as it can be
drawn from a broad universe of information. It would be malpractice to spend too
much time on such a search, disregarding other trial-related responsibilities out of
fear that some obscure source might cast doubt on your witness’s credibility. Cf.,
e.g., United States v. Jewell, 614 F.3d 911, 926 (8th Cir. 2010) (finding a district
court abused its discretion for failing to admit evidence that the adverse attorney in
a witness’s unrelated divorce proceedings found the witness untruthful).
We note, too, that even in the range of cases involving expert credentials, this
case falls on the more attenuated side. Sometimes, the failure to investigate an
expert’s credentials leads to the testimony being inadmissible. Cf. Polski v. Quigley
Corp., 538 F.3d 836, 839 (8th Cir. 2008) (citation omitted) (for expert testimony to
be admissible under Rule 702, “the proposed witness must be qualified to assist the
finder of fact”); see also Fed. R. Evid. 702. Unquestionably, a lawyer must practice
some degree of diligence in ensuring the foundation is laid for the admission of an
expert’s testimony. See People v. Cornille, 448 N.E.2d 857, 865–66 (Ill. 1983)

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(noting that “it is obvious that every party . . . has an obligation to verify the
credentials of its expert witnesses” because the expert’s credentials lay the
foundation for the admission of their testimony). Not only do these types of inquiries
involve important threshold matters, they are also simpler to verify by objective
criteria by using, e.g., verified copies of academic transcripts. Neither can be said
for the impeachment evidence at issue here.
We turn now to case law. We have not directly addressed the inquiry that
must be made into an expert’s credentials or credibility in a criminal case. In Dees
v. Caspiri, we suggested, in dicta, that counsel’s investigation “probably was
sufficient” where the expert came on the recommendation of an experienced attorney
and had years of experience in the field. 904 F.2d 452, 455 (8th Cir. 1990). Keeping
Dees in mind, we look to other courts for further guidance.
The Sixth Circuit is the only of our sister circuits to address a similar issue.
In Skaggs v. Parker, the court found that the failure to investigate an expert witness’s
falsified academic history was not deficient where counsel had a general familiarity
with and had used the witness before. 235 F.3d 261, 268 (6th Cir. 2000). The court
noted that “[g]iven the magnitude of what was at stake, and the centrality of [the
defendant’s] mental state to a legitimate defense, counsel should have taken more
time and given more thought to their expert witness.” Id. Nevertheless, considering
counsel’s familiarity with the witness, the actions “did not fall below an objective
standard of reasonableness under Strickland.” Id.
Two cases from the Northern District of Illinois are also helpful. In United
States ex rel. Hanna v. McGinnis, counsel’s failure to verify the credentials of an
expert was not deficient where an expert referral service supplied the expert. No. 90
C 7004, 1991 WL 203806, at *6 (N.D. Ill. Oct. 4, 1991). The court expressed
concern that requiring an attorney “to review every credential of each expert he
retains, even an expert provided and presumably screened by a referral service,
would impermissibly intrude into the realm of professional judgment and impose an
unrealistic burden upon counsel.” Id.

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In United States ex rel. Erickson v. Shomig, the court reached a different
conclusion. 162 F. Supp. 2d 1020 (N.D. Ill. 2001). There, the failure to investigate
the background of the sole mitigation witness was constitutionally deficient after
cross-examination showed that the expert lied about having psychology degrees and
the trial judge disqualified the witness as an expert. Id. at 1030, 1044. The court
rejected the argument that the attorney acted reasonably by relying on the
recommendation of the defendant’s family to hire the witness, saying that counsel
should have exercised greater diligence where the witness played a central role to
the defense’s lone mitigation strategy. Id. at 1044. In the court’s words, “[b]lindly
putting on a single witness at a capital sentencing hearing does not satisfy” the
obligation to discover and evaluate potential mitigating evidence. Id.
Consistent with Skaggs and Hanna, we conclude that McLaughlin did not
carry his burden to show that “counsel took an approach that no competent lawyer
would have chosen.” Dunn, 141 S. Ct. at 2410. Those cases stand for the general
proposition that counsel is not deficient where they reasonably rely on the
professional community to vet an expert. Accord Dees, 904 F.2d at 455; contra
Shomig, 162 F. Supp. 2d at 1044 (counsel deficient for relying on recommendation
of defendant’s family). Counsel did so here. Dr. Caruso was referred by a mitigation
specialist, and Kenyon checked Dr. Caruso’s curriculum vitae. The lawyers knew
that Dr. Caruso was a presenter on mitigation topics at national seminars and that he
had served as a witness in several other death penalty cases. McLaughlin has not
shown that, under these circumstances, no competent lawyer could have made the
choice to trust the legal community’s appraisal of Dr. Caruso.1
1 We recognize that reliance on a professional community alone may be
insufficient in certain cases. Sometimes, preparation and discussion with an expert
may reveal certain red flags about the expert’s credentials. But that is not this case.
McLaughlin does not point to any reason why the defense team should have made
further investigation, and Steele testified that he had “no reason to think there was
anything wrong with Dr. Caruso.” App. 2741.

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Even if further investigation was more prudent, it is not clear that the
investigation should have covered the falsified lab reports. Counsel should generally
investigate witness credentials to ensure testimony is admissible. See Shomig, 162
F. Supp. 2d at 1044; Cornille, 448 N.E.2d at 866. That is not what McLaughlin
argues. Instead, he suggests that a broader search into Dr. Caruso was necessary and
would have yielded impeachment information because a Google search returned
news about the falsified lab reports. But McLaughlin’s proposed search does not
address the purpose of that general duty—to ensure the expert’s admissibility. That
sort of search would not necessarily yield the news about falsified lab reports. And
surely, the Constitution does not require a scavenger hunt. See Rompilla v. Beard,
545 U.S. 374, 383 (2005) (“[T]he duty to investigate does not force defense lawyers
to scour the globe on the off chance something will turn up.”).
In sum, we find that McLaughlin did not overcome the presumption that
counsel performed reasonably by not investigating Dr. Caruso’s credentials.
B.
The State also challenges the district court’s finding that the failure to call a
psychiatrist prejudiced McLaughlin. To show prejudice, “Strickland asks whether
it is ‘reasonably likely’ the result would have been different.” Harrington v. Richter,
562 U.S. 86, 111 (2011) (citation omitted). “The likelihood of a different result must
be substantial, not just conceivable.” Id. at 112.
1.
The district court found that McLaughlin was prejudiced because if counsel
had further investigated Dr. Caruso they could have hired another psychiatrist like
Dr. Peterson. Dr. Peterson would have testified based on a face-to-face evaluation
of McLaughlin and made clinical observations about his frame of mind at the time
of the murder. He also would have testified that McLaughlin was under extreme
duress and had a reduced capacity to conform his conduct to the requirements of the

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law. Plus, the failure to put up this witness was aggravated by sentencing counsel’s
mention of Dr. Caruso during opening statements, and the jury could have thought
that the failure to call the witness was attributable to something else. This problem
was exacerbated by the Government’s closing argument, which pointed out that
McLaughlin did not present evidence about his mental state at the time of the murder.
In the district court’s view, this prejudice was important in the context of what
was already a close case. The jury found only one of the four aggravating factors—
depravity of mind. Dr. Peterson’s testimony would have weighed against that
finding. The jury also hung on the substantive issues of whether the mitigating
evidence outweighed the aggravating evidence and whether finding death was
appropriate. As the issues were close, the case could have been swayed by
introducing additional evidence relevant to the question. See Strickland, 466 U.S. at
696 (a “weakly supported” conclusion is “more likely to have been affected by errors
than one with overwhelming record support”).
The State disagrees. First, it says that the district court should not have
considered prejudice resulting from counsel mentioning Dr. Caruso during opening
argument. Second, the State argues that Dr. Peterson’s testimony would not have
changed the outcome of the case. The State says that even if Dr. Peterson’s
testimony had some probative value, the evidence showing depravity of mind was
too strong to be outweighed by the evidence in mitigation.
We start by narrowing the scope of our analysis. When considering prejudice,
the district court found that it was relevant that McLaughlin’s counsel told the jury
that it would hear from Dr. Caruso. This was error. We have said before that
“[h]abeas relief will not be granted based on the cumulative effect of attorney
errors.” Shelton v. Mapes, 821 F.3d 941, 951 (8th Cir. 2016); see also Forrest v.
Steele, 764 F.3d 848, 861 (8th Cir. 2014) (“By requiring that counsel’s performance
be ‘reasonable considering all the circumstances,’ Strickland does not purport to
aggregate each discrete and potentially unrelated claim of ineffectiveness into a
single performance inquiry.”) (cleaned up). By adding potential prejudice caused

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by counsel’s opening statements to its overarching analysis, the district court
violated this rule.
Moving on, we agree with the State that Dr. Peterson’s testimony would not
result in a different verdict. The State provided an overwhelming amount of
evidence in aggravation.2 McLaughlin stalked and terrorized Guenther before the
murder. He planned the attack, telling others that he was going to “fucking kill[]
that bitch” and saying he did not “want to be locked up” because of her. App. 2317–
18. He waited for Guenther outside of her work armed with a steak knife and
attacked her. While Guenther scratched and screamed, McLaughlin stabbed her
seven times and threw her to the ground, then strangled and raped her.3 McLaughlin
showed equal care for Guenther’s body, dragging it into his car, tying Guenther’s
legs together with twine, and dumping the body in the brush by the Missouri River.
One would expect a traumatic crime like this to induce immediate feelings of regret
and remorse. Instead, McLaughlin was seen the next day laughing and joking with
friends as though nothing happened. Even after his arrest, McLaughlin told one of
Guenther’s friends, “You’re next.” This evidence substantially outweighed any
evidence in mitigation.
2 The jury found McLaughlin acted with depravity of mind. “Depravity of
mind” requires evidence to support at least one of the following factors:
mental state of defendant, infliction of physical or psychological torture
upon the victim as when victim has a substantial period of time before
death to anticipate and reflect upon it; brutality of defendant’s conduct;
mutilation of the body after death; absence of any substantive motive;
absence of defendant’s remorse and the nature of the crime.
State v. Johnson, 284 S.W.3d 561, 586 (Mo. 2009) (citation omitted).
3 In McLaughlin’s initial state appeal, he argued that he could not have raped
Guenther because she was not alive at the moment of penetration. See McLaughlin
I, 265 S.W.3d at 269. The Missouri Supreme Court rejected that theory. In any
case, penetration after death would tilt even more in favor of finding McLaughlin
acted with depravity of mind. See id. at 277 (“[I]f, as [McLaughlin] argues, the rape
occurred wholly or partially after death, the crime would be even more depraved.”).

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Plus, Dr. Peterson’s evidence would have been at least somewhat cumulative
to Dr. Cunningham’s testimony. Both interviewed McLaughlin and examined his
ability to conform his actions to societal standards. At trial, Dr. Cunningham
acknowledged that McLaughlin had a choice when he killed Guenther, but that the
decision was influenced by certain “risk” and “protective” factors throughout his
life. Dr. Peterson would have testified that McLaughlin was suffering extreme
emotional disturbance when Guenther rejected him. This “impaired his capacity to
conform his conduct to the requirements of law.” McLaughlin Br. 12. Dr. Peterson
and Dr. Cunningham’s accounts overlap significantly because both suggest that the
rejection by Guenther triggered pains from McLaughlin’s childhood, impacting his
decision to kill.
At the same time, we do not discount McLaughlin’s argument to the contrary.
McLaughlin says that there is a difference in the testimonies. Dr. Peterson would
have been able to testify about McLaughlin’s mental state at the time of the murder.
We recognize that the testimony of Dr. Peterson may have been better at establishing
this. In some ways, it would have been the denouement of the mitigation case: while
the testimony of the other three doctors set up the circumstances surrounding
McLaughlin’s life and his hardships, Dr. Peterson could have told the jury what the
effect of all these circumstances was at the critical moment. We understand the
effect that this might have had on the overall trial strategy, but considering the
substantial overlap and the weight of the evidence in aggravation, we do not think
this evidence would have shown a “substantial” likelihood of a different result.
Even if Dr. Peterson’s testimony was not cumulative, some of it is undermined
by the record. McLaughlin says that Dr. Peterson would have testified that
McLaughlin was unable to appreciate the criminality of his conduct. But
McLaughlin’s actions to cover up the murder say otherwise. See United States v.
Hiebert, 30 F.3d 1005, 1007 (8th Cir. 1994) (“A defendant’s attempt to conceal his
commission of a crime suggests that he knows the action is wrongful . . . .”). After
killing Guenther, McLaughlin tried to dump Guenther’s body in the Missouri River.
The next day, he cut up sections of fabric from his car’s backseat and bought bleach

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to clean the blood. He knew murder was a crime. Even before the murder,
McLaughlin knew that his other actions towards Guenther were unlawful. See id.
(“[T]he defendant’s knowledge that one crime was wrong evidences that he
understood that other criminal acts were inappropriate.”). And, one of the
motivating factors in killing Guenther was that he did not “want to be locked up” on
the other charges Guenther filed against him. App. 2318. Put together, these actions
are incompatible with Dr. Peterson’s conclusion.
We conclude that there was not a substantial likelihood of a different result.
The evidence in aggravation of the offense far outweighed the evidence in
mitigation—even if bolstered by Dr. Peterson’s examination. While we think that
the case is made closer by the jury deadlock, we find that the new evidence is not
enough to call into question the soundness of the verdict. See Boyd v. Allen, 592
F.3d 1274, 1303 (11th Cir. 2010) (denying ineffective assistance claim in jury
override case despite noting that “prejudice ‘is more easily shown’” in such cases)
(citation omitted).
2.
On the issue of prejudice, the state habeas court found that McLaughlin was
not prejudiced by sentencing counsel’s failure to call a psychiatrist. The prejudice
analysis is the same one presented here: whether there is a substantial likelihood of
a different result if McLaughlin had called Dr. Peterson. Under 28 U.S.C. §
2254(d)(1), we can only provide habeas relief “with respect to any claim that was
adjudicated on the merits in State court proceedings” if “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.” “Taken together, [the Antiterrorism and Effective Death
Penalty Act of 1996] and Strickland establish a ‘doubly deferential standard’ of
review.” Williams v. Roper, 695 F.3d 825, 831 (8th Cir. 2012) (citation omitted).
Even if our analysis above is mistaken, we do not think the state court’s decision
“was contrary to, or involved an unreasonable application of, clearly established

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Federal law.” The required deference in Section 2254(d)(1) imposes an independent
ground for reversal.
III.
The State argues that the district court should not have considered
McLaughlin’s failure to investigate claim because it was procedurally defaulted
when he failed to raise it in his state habeas case. “[A] federal court will not review
the merits of claims, including constitutional claims, that a state court declined to
hear because the prisoner failed to abide by a state procedural rule.” Martinez v.
Ryan, 566 U.S. 1, 9 (2012). In those cases, the state court’s judgment “rests on
independent and adequate state procedural grounds,” and normally, we cannot grant
relief. Coleman v. Thompson, 501 U.S. 722, 736 (1991).
To excuse procedural default, McLaughlin must show that his post-conviction
counsel was defective with respect to a “substantial” claim. Martinez, 566 U.S. at
14. Post-conviction counsel cannot be ineffective for failing to raise a meritless
claim. See Grubbs v. Delo, 948 F.2d 1459, 1464 (8th Cir. 1991) (counsel on direct
appeal cannot be considered ineffective for having failed to raise a meritless issue).
As McLaughlin’s failure to investigate claim is meritless, the claim was not
“substantial,” and McLaughlin’s procedural default is not excused.
IV.
The district court also found that two constitutional issues marred
McLaughlin’s sentencing. First, it reasoned that the jury instructions violated Mills
by requiring a jury to unanimously find that mitigating factors outweighed
aggravating factors. Second, it found that Missouri’s capital sentencing system,
which permits the judge to make findings of mitigating factors, violates Ring
because it unconstitutionally vests the authority to make factual findings in the
judge.

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A.
The State disputes the district court’s finding that the sentencing instructions
violated Mills, arguing that the district court misunderstood Mills. We agree. Mills
held that capital sentencing instructions may not “preclude[] [jurors] from
considering any mitigating evidence unless all 12 jurors agreed on the existence of
a particular such circumstance.” 486 U.S. at 384; see also Griffin v. Delo, 33 F.3d
895, 906 (8th Cir. 1994). In other words, jurors must be allowed to make their own
decisions on which mitigating factors they think weigh against the aggravating
factors. The instructions here permitted that—they did not require unanimity on any
specific mitigating factor. See App. 1603 (“Does the jury unanimously find that
there are facts and circumstances in mitigation of punishment sufficient to outweigh
facts and circumstances in aggravation of punishment?”). In Griffin, we upheld a
similar instruction in a Missouri death penalty case that required unanimity but
allowed the jurors to consider multiple mitigating circumstances. 33 F.3d at 905.
We reverse the district court’s conclusion to the contrary.
B.
The State also challenges the district court’s application of Ring. This was
addressed in McLaughlin’s initial appeal to the Missouri Supreme Court. Under
AEDPA, the availability of federal habeas relief is narrow for claims “adjudicated
on the merits” in state-court proceedings. 28 U.S.C. § 2254(d). A state prisoner
must show that the state court decision (1) “was contrary to, or involved an
unreasonable application of, clearly established Federal law, as determined by the
Supreme Court of the United States”; or (2) “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). “‘[I]f a habeas court must extend a rationale
before it can apply to the facts at hand,’ then by definition the rationale was not
‘clearly established at the time of the state-court decision.’” White v. Woodall, 572
U.S. 415, 426 (2014) (citation omitted).

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In Ring, the Supreme Court held that “[c]apital defendants . . . are entitled to
a jury determination of any fact on which the legislature conditions an increase in
their maximum punishment.” Ring, 536 U.S. at 589. The district court found that
“[u]nder Missouri law, the weighing of mitigating and aggravating circumstances is
a finding of fact” that can only be performed by the jury. D. Ct. Dkt. 77 at 72. To
get there, the court relied on State v. Whitfield, 107 S.W.3d at 261, which held as
much.
But the tides have changed. In McLaughlin’s initial appeal, the Missouri
Supreme Court found that the rule from Whitfield was inapplicable. See
McLaughlin I, 265 S.W.3d at 263. And, since, the Missouri Supreme Court has
disavowed Whitfield’s interpretation of the statute. See Zink v. State, 278 S.W.3d
170, 192–93 (Mo. 2009) (en banc) (counsel was not ineffective for failing to raise
“meritless” argument that sentencing violated Ring because the weighing step is not
a finding of fact); see also Wood, 580 S.W.3d at 585 (collecting cases). We do not
sit in judgment of a state supreme court’s interpretation of state law, and the district
court should not have, either. Missouri’s statute never required the weighing of
mitigating and aggravating circumstances to be a finding of fact, see Wisconsin Cent.
Ltd. v. United States, 138 S. Ct. 2067, 2074 (2018) (“every statute’s meaning is fixed
at the time of enactment”) (emphasis omitted), so it is impervious to McLaughlin’s
challenge.
Nor can the requirement to find mitigating factors beyond a reasonable doubt
be found in any Supreme Court precedent. As a constitutional threshold, the Court
has found that “[t]o render a defendant eligible for the death penalty in a homicide
case, . . . the trier of fact must convict the defendant of murder and find one
‘aggravating circumstance’ (or its equivalent) at either the guilt or penalty phase.”
Tuilaepa v. California, 512 U.S. 967, 971–72 (1994). But the Court has refused to
adopt definitive standards of proof in the context of mitigating factors, observing
that “the ultimate question whether mitigating circumstances outweigh aggravating
circumstances is mostly a question of mercy.” Kansas v. Carr, 577 U.S. 108, 119
(2016). We will not speculate whether the Court will one day require mitigating

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factors to be found by a jury beyond a reasonable doubt. For our purposes today,
we need only recognize that requiring as much would be an extension of Ring,
placing it outside our authority under Section 2254(d). See White, 572 U.S. at 426.
IV.
The judgment of the district court is reversed. The case is remanded for
proceedings consistent with this opinion.
ERICKSON, Circuit Judge, concurring.
I write separately to highlight and join the district court’s concerns about
defense counsel’s failure to conduct any type of investigation about Dr. Caruso, an
expert that counsel anticipated would be his star witness during the penalty phase.
Decades ago, the United States Supreme Court acknowledged “that death is a
punishment different from all other sanctions in kind rather than degree.” Woodson
v. North Carolina, 428 U.S. 280, 303–04 (1976) (citations omitted). “Because of
that qualitative difference, there is a corresponding difference in the need for
reliability in the determination that death is the appropriate punishment in a specific
case.” Id. at 305.
Here, the undisputed record shows that the impeachment evidence at issue
was readily available and easily ascertainable. Once Dr. Caruso made counsel aware
of the potential impeachment evidence, the third “hit” on counsel’s Google search
produced a June 1994 Office of Research Integrity, U.S. Public Health Service
document. That document provided information about Dr. Caruso’s misconduct,
explaining that Dr. Caruso, while a student in the department of psychiatry, “altered,
fabricated, and destroyed primary laboratory data.”
As recognized by the majority, lawyers are tasked with exercising some
degree of diligence with regard to expert testimony. I am not convinced that

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McLaughlin failed to meet his burden of showing counsel performed deficiently.
Counsel’s conduct in vetting the expert witness—one that he believed would be the
most significant penalty phase witness—was limited to two things: (1) a review of
the expert’s curriculum vitae, and (2) a mitigation specialist’s recommendation
based solely on watching the expert present at a seminar. It is certainly debatable
whether this vetting process meets either the low diligence standard noted by the
majority or falls within the range of acceptable professional competence. Indeed,
counsel admitted on the record at trial that he believed he was ineffective in the
handling of Dr. Caruso. Counsel’s concern was not that he decided against calling
Dr. Caruso to testify, but that he did not investigate Dr. Caruso’s background and
when Dr. Caruso pointed out to him impeachment evidence, counsel failed to take
the time to consider the significance of the information and proceeded to mention
Dr. Caruso’s anticipated testimony during opening statements. It is these decisions
that counsel acknowledged had a prejudicial effect. Trial. Tr. 1953–55.
In spite of my concerns related to professional competence, I concur in the
result because, after carefully reviewing the record, I agree with the majority that
McLaughlin is unable to show that counsel’s performance prejudiced him. Even
without Dr. Caruso, as noted by the Missouri Supreme Court in McLaughlin v. State,
378 S.W.3d 328, 344 (Mo. 2012), defense counsel presented significant evidence
documenting McLaughlin’s intelligence issues and long-standing mental health
issues ranging from personality disorders to neurological problems. It is beyond
question that the State capitalized on the absence of a defense expert who had talked
to or evaluated McLaughlin recently. Specifically, the State argued that
McLaughlin’s evidence should be discredited for a number of reasons, including the
fact that the experts who testified had not seen or treated McLaughlin for 24 years.
Notwithstanding these arguments, before the jury was extensive testimony about
McLaughlin’s life and his characteristics, including:
• McLaughlin’s attachment and trust issues stemming from his
traumatic childhood;
• McLaughlin’s early antisocial behavior;

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• McLaughlin’s association with deviant peers;
• McLaughlin’s anxiety issues;
• McLaughlin’s history of treatment for depression, including
McLaughlin’s admission to the hospital for six days, which
occurred four months before the murder, because of major
depressive disorder triggered by the breakup with the victim;
• McLaughlin’s intellectual deficiencies and neuro-developmental
problems and how they impact McLaughlin’s behavior and
understanding of the world;
• McLaughlin’s problems with impulse control; and
• Each of the risk factors present in the models used by the
Department of Justice that “push[ed] [McLaughlin’s] ramp at a
very high angle in terms of predisposing him toward both alcohol
abuse and towards criminality.”
On the evidence before it, the jury was left with no reason to believe that any
of McLaughlin’s intellectual or mental health issues that began as a child had
resolved or improved over time. Defense counsel presented ample evidence for a
jury to find that McLaughlin was undergoing a mental health crisis at the time of the
murder. The jury, however, could not unanimously agree on whether the mitigating
factors outweighed the aggravating factor of depravity of mind. On this record, I
cannot say that testimony from Dr. Caruso, or an alternative psychiatrist, would have
made a difference in the outcome. Because McLaughlin has failed to demonstrate a
reasonable probability that the outcome would have been different, McLaughlin’s
ineffective assistance of counsel claim fails.
With regard to the constitutional claims regarding the jury instructions and
Missouri’s death penalty scheme, the Missouri Supreme Court in State v. Wood, 580
S.W.3d 566, 586–87 (Mo. 2019), made clear that the only factual finding that must
be made by the jury under its death penalty statute pertains to the existence of at
least one aggravating circumstances (the eligibility step). The jury in this case made
the necessary eligibility finding and the judge acted within his sentencing discretion

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when he decided on a sentence of death. I cannot say that the Missouri Supreme
Court’s decision is contrary to, or involves an unreasonable application of clearly
established Supreme Court precedent, or that the decision is based on an
unreasonable determination of the facts. For these reasons, I concur.
______________________________

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