Capital sentencing and neuropsychiatry
Samuel Jan Brakel
 Douglas E. Tucker
SimpleOriginal

Summary

Neuropsychiatric input in capital sentencing has grown, including mental health factors in criminal behavior. This review covers legal theories and data from forensic neuropsychiatrists, emphasizing the gravity of the death penalty.

Capital sentencing and neuropsychiatry

Keywords aggravation; capital punishment; criminal sentencing; death penalty; ethics; forensic neuropsychiatry; intellectual disability; juvenile offenders; mitigation, psychopathy; risk assessment

Abstract

The neuropsychiatric contribution to capital sentencing proceedings has grown substantially in recent decades as the consideration of neurological and psychiatric factors in criminal behavior has been increasingly accepted as relevant to the quest for justice. This review article will focus on the legal theories underlying neuropsychiatric input into capital sentencing decisions, as well as some of the investigative techniques and resulting data which may be offered by forensic neuropsychiatrists in this context. The death penalty is unique in its severity and irreversibility, as the courts, including the U.S. Supreme Court, have noted repeatedly. “Death is different,” and the recognition of this has generated a set of court decisions and statutes pertinent specifically to capital proceedings, both procedural and substantive.

1 | INTRODUCTION

The neuropsychiatric contribution to capital sentencing proceedings has grown substantially in recent decades as the consideration of neurological and psychiatric factors in criminal behavior has been increasingly accepted as relevant to the quest for justice. This review article will focus on the legal theories underlying neuropsychiatric input into capital sentencing decisions, as well as some of the investigative techniques and resulting data which may be offered by forensic neuropsychiatrists in this context. The death penalty is unique in its severity and irreversibility, as the courts, including the U.S. Supreme Court, have noted repeatedly. “Death is different” (Atkins v. Virginia, 2002b; Furman v. Georgia, 1972c; Gregg v. Georgia, 1976b), and the recognition of this has generated a set of court decisions and statutes pertinent specifically to capital proceedings, both procedural and substantive. For example, two criminal offender sub-populations have relatively recently been determined by the U.S. Supreme Court to be categorically exempt from capital punishment. These are (1) individuals charged with capital crimes who suffer from an intellectual disability (previously termed “mental retardation”) (Atkins v. Virginia, 2002a), and (2) juvenile offenders who committed their otherwise potentially capital crime(s) while under the age of 18 (Roper v. Simmons, 2005).

2 | A BRIEF “MODERN” HISTORY OF CAPITAL PUNISHMENT IN THE U.S.

The modern history of capital punishment in the United States begins with the U.S. Supreme Court's Furman decision in 1972 (Furman v. Georgia, 1972a). Furman v. Georgia was brought at a time when 40 of the 50 states still had laws permitting the death penalty, although public support for the penalty was at an historic low point, with polls showing that slightly less than half of the national population approved of it. Similar polling a generation later indicated 80%-plus in favor of capital punishment as an available option, a turn-about of stunning size and rapidity which has presented the question of whether and how courts, especially the U.S. Supreme Court, should respond to such major shifts in public opinion. Today, public support for the penalty is dropping again, based in part on science-aided revelations of false convictions.

Furman consolidated three criminal cases involving three different defendants, including a rape case from Texas (Branch v. State, 1969), another rape case from Georgia in which the death penalty had been imposed (Jackson v. State, 1969), and a robbery/murder case from Georgia which had also resulted in a death sentence (Furman v. Georgia). The Court focused on the Furman murder conviction in the consolidated case, as the name indicates. The question of whether death may be an appropriate punishment for adult rape was not addressed directly until 5 years later (Coker v. Georgia, 1977); other crimes potentially punishable by death in Georgia at the time of Furman included armed robbery, aggravated kidnapping, treason and aircraft hijacking. Challenging the validity of Georgia's then-capital punishment statute on several grounds, including its per se unconstitutionality (i.e., violation of the 8 th Amendment's prohibition against cruel and unusual punishment), the case presented an opportunity for the Court to effectively abolish the death penalty for the entire nation—an outcome fervently hoped for by the case's primary litigators and allied advocates. The Court, however, did not take this route, nor did it come close. In a one-paragraph “per curiam” opinion (i.e., an appellate court decision made collectively by multiple judges), it reversed the trial results in each case. When it came to the reasons, however, the nine Justices differed, resulting in a chaotic amalgamation of opinions spread over more than 200 pages, which led to the emergence of a much narrower rule. Only two Justices agreed that the death penalty was per se unconstitutional, irrespective of the facts of the case or the state of the law. They were joined by three Justices who objected to the particularities of the Georgia law as written as well as applied, making for a majority of 5–4—against four dissenters who saw no problem with either of these issues. The key invalidating feature of Georgia's law (as per the three decisive votes) was the lack of guidance it provided for the jury in making the capital decision. This left the jury with “unfettered” discretion, leading to “haphazard” or “arbitrary” imposition of the ultimate penalty (the words “capricious,” “wanton” and even “freakish” were also used [Brakel & Brooks, 2001; Furman v. Georgia, 1972b; Gregg v. Georgia, 1976a]), thus providing no meaningful basis for distinguishing between the few cases in which death was imposed from the many in which it was not. Because the death penalty statutes of all other states suffered from essentially the same defect, the penalty was in effect invalidated nationally, and a nation-wide moratorium on its application ensued.

Since the articulated defects were particular to the content of the laws, rather than a per se condemnation of state-imposed death for criminal behavior, legislators from 37 states proceeded to rewrite their statutes in an effort to comply with the new standards. Since Georgia was the focus of the litigation that invalidated the statutory status quo in 1972, its revised scheme was the first one to be tested for its constitutionality (as expected though not required). This occurred 4 years later when the U.S. Supreme Court took on the case of Gregg v. Georgia (Gregg v. Georgia, 1976c). The decision in this case approved a series of mostly procedural reforms to Georgia's death penalty statute, such as direct review of any death sentence by the state's Supreme Court, including specific review for unfair bias or arbitrariness. The key substantive change in the Georgia statute, however, affirmed by the Court and in due course copied by all other states, was the enumeration of a list of aggravating and mitigating factors that would now guide the jury in deciding between life and death. These factors would appropriately “channel” the jury's discretion in order to avoid arbitrary and impermissibly biased decisions. The jury would be informed of the aggravating circumstances of the crime (e.g., the behavior and background of the criminal, the characteristics of the victim) as well as the mitigating factors (e.g., actual or psychological compulsion, lack of criminal history), weigh them against each other, and justice would thus be served. Another, very different, method to curb jury arbitrariness used at that time in some states, particularly North Carolina, Louisiana and Nevada, was to take away all of the jury's discretion. Under this approach, the death penalty was mandatory upon conviction of certain high crimes, for example, first-degree murder of any citizen, the killing of a police officer or prison guard, or (shifting focus from victim to perpetrator) homicide by an inmate already serving a life sentence without parole. However, in a series of decisions dealing with each of these categories, the U.S. Supreme Court eventually invalidated them all on the ground that every death penalty decision must be individualized to the offense and the offender (Roberts v. Louisiana, 1977; Sumner v. Shuman, 1987; Woodson v. North Carolina, 1976).

3 | MITIGATION, AGGRAVATION AND RISK ASSESSMENT

Throughout the course of psychiatry's involvement in the legal domain, including the criminal justice system in particular, forensic psychiatrists have commonly been asked to address mitigating issues related to mental state and psychopathology. Aggravating factors have been less frequently addressed, although forensic mental health experts have offered or been challenged to offer opinions on these as well. In fact, mental health disorders and deficiencies are a major feature of the list of mitigating factors in almost all states. The now-defunct Illinois death penalty statute, for example, initially included “extreme mental and emotional disturbance” as one of its seven enumerated mitigating circumstances; it later added the defense option of proving that the offender “suffer[ed] from a reduced mental capacity” at the time of the crime (Brakel & Brooks, 2001; Furman v. Georgia, 1972b; Gregg v. Georgia, 1976a). Earlier, a major precedent-setting decision by the U.S. Supreme Court in the late 1970's (Lockett v. Ohio, 1978) featured a statute containing as one of three mitigating factors whether or not the defendant's crime was “the product of psychosis or mental deficiency.” The relevance of neuropsychiatric opinion to these mitigating considerations is a question that is part of the more general debate on the relevance of increasingly sophisticated biologically-based evidence to the law's essentially moralistic questions about responsibility/accountability. There are prominent legal thinkers who believe the impact is or should be zero or next-to-zero; others who believe it will and should revolutionize both attitudes and outcomes; and some who choose a safer ground somewhere in the middle. Whatever the outcome of this debate, it is certain that forensic psychiatrists will continue to be asked to perform mitigation evaluations. The challenge for the forensic evaluator, as always, will be to respond to the precise language of the statute in the particular jurisdiction in which their service is requested and offered. The only thing different or unique about the capital context is that the stakes are very high, that is, as high as they can be for that defendant.

States often have a final over-arching jury instruction process built on top of the aggravating/mitigating substructure. Thus, in Texas at the time the U.S. Supreme Court's major rulings in this area were rendered (some technical changes have come since, see Penry v. Johnson, 2001, et seq. [Penry v. Johnson, 2001]), the capital sentencing jury which convicted the defendant in the guilt phase of the trial was required to answer three questions at the sentencing phase in order to decide between life and death. Two of these questions are “legal” in that they focus on the defendant's intent at the time of the crime, an issue presumably already considered during the guilt phase. The third requires an assessment of future dangerousness, that is, whether or not there is “a probability” the defendant will commit further serious crimes if not executed (Estelle v. Smith, 1981). The performance of violence risk assessments by mental health professionals in the capital context was approved by the U.S. Supreme Court as far back as 1983 in Barefoot v. Estelle (Barefoot v. Estelle, 1983), over the objections of psychiatric organizations which expressed concern at that time about the lack of evidence that psychiatrists could predict future behavior, especially if such predictions could be used to facilitate imposition of the death penalty. Violence risk assessments can be helpful to the defense, too, however, especially when these indicate that the defendant is at relatively low risk. For example, the often-mandatory alternative to the death penalty in many jurisdictions is life imprisonment, and living conditions in the highly structured and monitored environment of a correctional facility are almost certainly quite different from those that prevailed at the time of the original offense, usually resulting in lower risk of recidivism.

The clinical diagnosis of psychopathy has particular relevance to violence risk assessments, as it has been repeatedly validated as a robust risk factor for criminal violence in a variety of contexts and populations (Rice et al., 2013). As a result, the diagnosis of psychopathy is generally not considered to be advantageous for the defendant, but this may change as the underlying neurobiology becomes increasingly elucidated. Genetic and neurodevelopmental factors related to life-course persistent antisocial behavior, including psychopathy in particular, have been identified beginning in earliest childhood, and could as well be considered legally mitigating. For example, a child murder case from Illinois dating back to 1983 came to its final resolution in 2009 when defendant Brian Dugan pled guilty to the offense. This occurred after three others had been formally accused of the crime, two of whom were convicted and sentenced to death, but later exonerated in part due to Dugan's confession (Hagerty, 2010). Following Dugan's 2009 plea, defense mental health experts testified in mitigation at the sentencing phase about the genetic and neurobiological dimensions of psychopathy. Although the defense was unsuccessful and Dugan was ultimately sentenced to death, the case highlighted the potential relevance of neurological underpinnings for at least some criminal behavior, and the appreciation of this has been a major foundation for the developing new field of “Neurolaw” (Meynen, 2016). Dugan himself avoided execution when 2 years later the Illinois legislature abolished capital punishment, a move preceded by a state-wide moratorium on the penalty in 2000 declared by then-Governor Ryan, whose confidence in the proper administration of the penalty was undermined in part by the false convictions in the Dugan case.

4 | THE EVIDENTIARY LATITUDE OF THE SENTENCING PROCESS

There are generally very few constraints on the nature and scope of evidence that may be presented in the sentencing phase of any trial, whether capital or not, and especially for the defense. While evidence-admissibility tests such as Frye (Frye v. United States, 1923) or Daubert (Daubert v. Merrell Dow Pharmaceuticals, 1993) are often decisive points of contention in pre-trial maneuverings or at trial in both civil and criminal cases, the courts will admit a much wider range of defense evidence at the sentencing phase (Brakel et al., 1996). Defense attorneys who fail to raise even somewhat plausible mitigating themes or evidence can be sued for incompetent representation, even when the evidence may lie outside any statutory enumeration of these issues. The U.S. Supreme Court decided several decades ago (Lockett v. Ohio, 1978) that all mitigating evidence in capital cases is admissible, irrespective of statutory limits, despite Justice Scalia's objection that it undid post-Furman reforms which specified what evidence juries were to consider. Regardless of the offense or the apparent motive, all defendants are entitled to the benefits of evidentiary latitude in the capital sentencing process. In fact, many capital sentencing cases feature an ABA-recommended Mitigation Report, put together by a mitigation specialist, that is expected to advocate for the defense.

5 | THE CATEGORICALLY EXCLUDED

As indicated at the beginning of the article, mentally retarded/intellectually disabled (MR/ID) and juvenile offenders who commit crimes that for others could merit the death penalty are, via the U.S. Supreme Court's interpretation of the 8 th Amendment prohibition against cruel and unusual punishment, exempt from the penalty. The issue is one of culpability, and the Court has concluded that members of these two classes are a priori less culpable than other capital offenders, who are intended to be the most heinous of murderers, that is, those guilty of “the most serious adult criminal conduct” (Atkins v. Virginia, 2002a). The reasoning behind this conclusion is virtually identical for both classes, and the opinions of the Justices, including the dissents, are quite similar. Both cases, decided only 3 years apart, overruled relatively recent Supreme Court precedents to the contrary, and the majority in both cases claimed its decision was compelled by changes in the country's laws, reflecting changes in “contemporary standards of decency” (the test for constitutionality as per an earlier precedent [Trop v. Dulles, 1958]). The precedential case for MR/ID offenders (Penry v. Lynaugh, 1989) held that death penalty decisions should be individualized irrespective of certain common categorical characteristics, since there would be a “false homogenization” of the class if no consideration were given to the many individual differences within the group. The precedential cases for juvenile offenders were earlier Supreme Court rulings permitting capital punishment for defendants younger than 18 at the time of their offense, that is, 16 or 17 in some states (Stanford v. Kentucky, 1989).

6 | NEUROPSYCHIATRY AND CAPITAL SENTENCING FOR INTELLECTUALLY DISABLED OFFENDERS

There is significant potential for expansion of neuropsychiatry's role in capital sentencing of MR/ID offenders, since the Court's ruling in Atkins essentially left the definition of this class up to forensic mental health professionals by deferring to the states' legislatures the details of implementing its holding. In delegating this task, the Court noted that the statutes on the books already conformed generally to clinical definitions set forth by the American Association on Mental Retardation, currently called the American Association on Intellectual and Developmental Disabilities (AAIDD), as well as the American Psychiatric Association (APA) (Atkins v. Virginia, 2002a). Psychiatric concepts were thus indirectly endorsed for definition of the law's terms, setting the stage for additional mental health input into diagnostic investigations and testimony in specific cases. The AAIDD and APA definitions make reference to substantial deficits in intellectual and adaptive functioning across several critical skills areas, with age of onset often identified as a third and less important “prong.” The issues of intellectual and adaptive functioning are of course both amenable to forensic neuropsychiatric analysis, while age of onset is usually a somewhat simpler historical inquiry, involving review of school records and the like that can be carried out by a range of health professionals. Controversies about scoring and interpretation of results tend to be political in nature, although they do involve scientific considerations which may benefit from neuropsychiatric input. These controversies include how to account for the Flynn effect (the substantial and worldwide increase in intelligence test scores that has been observed throughout the 20th century), and whether or not to norm test results for race in capital cases (not favored by the defense). The state statutes are likely to use language similar to that referenced in the Atkins decision, although as always, the forensic practitioner must be familiar with the statute of the particular jurisdiction involved, and respond to its specific language.

By contrast, the exemption dictated by Roper v. Simmons for juveniles is simply a particular chronological age (i.e., under 18 years at the time of the offense), and this fixed threshold is not an issue which is open to psychiatric interpretation. Mental health professionals did provide input to the Court's decision to set the age at 18, but their contribution ended with that decision, and it is unlikely that the Court will be motivated to reconsider this threshold at any time in the foreseeable future.

7 | CASE EXAMPLE

AW is a 22-year old AA male defendant charged with three counts of first-degree murder, with the special circumstance of multiple murders making him eligible for the death penalty. The killings occurred in the context of an emotional argument with his girlfriend and her mother during which he felt attacked and belittled. He reported having dissociative symptoms during this argument (felt that he was “outside his body”), and described how he went to his vehicle, retrieved a pistol, and returned to the house where he shot and killed all the occupants, including his pregnant girlfriend, her unborn fetus, her mother, and her pre-teen brother. These acts were reported by the defendant to be immediately followed by his “breaking down crying” in a state of confusion and intense remorse, and shortly thereafter turning himself in to the police, saying “I don't know why I killed them.”

Extensive family interviews and social service records indicated a history of recurrent physical, emotional and sexual abuse during childhood, including the repeated witnessing of domestic violence. There was a pattern of disinhibited, impulsive aggression since age six, with documented school behavior problems including hyperactivity, disruptiveness, short attention span, and frequent fighting, which resulted in two suspensions and placement in special education from third to sixth grades (for behavior problems rather than a learning disability). He reportedly continued to experience episodic violent rage episodes as a teen and young adult, several of which led to arrest and prosecution for assault and recurrent domestic violence. He was diagnosed in childhood with several neurodevelopmental disorders including Attention Deficit Hyperactivity Disorder, Oppositional Defiant Disorder, Conduct Disorder, Enuresis, and Speech Impediment, but no significant history of substance abuse was noted. He was additionally diagnosed by the defense neuropsychiatrist with untreated Persistent Depressive Disorder (Dysthymic Disorder), Paranoid Personality Disorder, and Intermittent Explosive Disorder. The family history was significant for extensive mental illness on his mother's side, including unipolar and bipolar mood and psychotic symptoms in the mother, maternal grandmother, and several aunts and cousins.

Initial defense mental health evaluation included a standard neurological examination, neuropsychiatric assessment, and neuropsychological testing, all of which were basically normal, including average-range IQ and academic abilities without evidence of significant cognitive impairment. A structural brain MRI was likewise read by a forensic neuroradiologist as essentially normal, but subsequent quantitative volumetric MRI analysis with statistical comparison to normative databases found substantial gray matter volume reductions in about 30% of measured regions. Most cortical regions supporting basic cognitive skills such as memory and attention were reasonably intact, while areas supporting the processing of emotional stimuli and the emotional regulation of behavior such as the amygdala and orbitofrontal cortex showed reduced volumes (Radeljak et al., 2010). Diffuse Tensor Imaging demonstrated reduced fractional anisotropy values in about 25% of white matter fiber tracts, indicating disrupted connectivity particularly in the genu of the corpus callosum and the left uncinate fasciculus, which are relevant to behavioral control and emotional processing (Ling et al., 2019).

Functional brain scanning with fMRI showed substantial abnormalities in functional connectivity in frontal regions, and disrupted connectivity within the default mode network (Espinoza et al., 2018). Quantitative electroencephalogram (EEG) findings indicated substantial abnormalities in both spectral content and connectivity, including reduced posterior delta and theta, and increased midline beta, along with anomalies in coherence and amplitude asymmetry. There was evidence of impaired sensory gating and impulse control, although memory and orienting functions were intact (Calzada-Reyes et al., 2013). Finally, neurogenetic analysis for behavioral genotyping found multiple polymorphisms associated with increased risk for impulsive violence in the context of an abusive upbringing, including highrisk alleles in the genes coding for MAO-A, COMT, SLC6A4, and DRD4 (Bernet et al., 2007; Raad & Appelbaum, 2015).

Testimony in mitigation was given by the defense neuropsychiatrist at the penalty phase of the trial, indicating that the location and distribution of reduced brain volume in the defendant's brain, particularly in frontal, limbic and paralimbic areas, would be expected to reduce his ability to exercise appropriate social judgment and control violent impulses, especially when under stress or threat. Despite the presentation of this uncontroverted neuropsychiatric evidence to the jury, however, the outcome was a verdict of death.

8 | DISTINCTION BETWEEN MR/ID AND MENTALLY ILL DEFENDANTS

The law's treatment of MR/ID capital offenders is often contrasted with the approach to mentally ill offenders, with concerns expressed about unfair discrimination since mentally ill capital offenders as a class are not also exempt from the death penalty. One reason for this may be that, although the intellectually disabled are certainly not a homogeneous class, the mentally ill are even less so. The resulting situation is that the factors that may be considered to potentially spare mentally ill capital offenders from the death penalty can only be invoked on an individual basis, whereas the MR/ID defendant, in addition to asserting these individual factors at or pretrial, may also be able to prove the right to be exempt at sentencing based on a categorical claim. These individual trial defense options include potential incompetence to stand trial, insanity (or diminished capacity/responsibility) at the time of the crime, incompetence to be sentenced, and/or incompetence to be executed. The defendant's competency to proceed in the criminal context is considered to be a fundamental Constitutional right, including competence to stand trial (Pate v. Robinson, 1966) and competence to be executed (Ford v. Wainwright, 1986). The various forms of incompetency, if proved, tend to simply slow or halt the process and postpone the final outcome. Insanity at the time of the offense, however, is relevant to guilt/culpability and affects the overall disposition of the case, although the insanity defense is not considered to be a Constitutional right (Kahler v. Kansas, 2020).

It is important to note that all criminal competencies follow the guiding precedent of Dusky v. U. S. (1960), in that the defendant's factual comprehension of the process is not enough, and there must be a “rational” understanding as well (Dusky v. United States, 1960). The U.S. Supreme Court reiterated this in Panetti v. Quarterman (2007), a case involving competence to be executed in which the lower court's finding that a delusional death row inmate's ability to understand factually what execution meant and why it was imposed, as well as the link between the two, was insufficient if it was not also a “rational” understanding (Panetti v. Quarterman, 2007).

Defense options for alleged mentally ill offenders in the guilt phase include the insanity defense and in some states a plea of Guilty but Mentally Ill (GBMI). Legal insanity can also play a role in the capital sentencing phase, in that the finder of fact (jury or judge) that heard all the evidence (including any on mental illness) and determined guilt, is also the decider of the ultimate sentence. The guilt-phase evidence related to psychiatric symptoms at the time of the offense can again be invoked and refreshed at the penalty phase by either side, as long as the defendant initiated an insanity claim and/or adequate notice was given (Estelle v. Smith, 1981). The plea of GBMI presents a unique issue with regard to the relevance of guilt-phase evidence that may later be considered at sentencing. In People v. Crews, a 1988 death penalty case before the Supreme Court of Illinois, the question was whether a verdict of GBMI based on the finding of statute-defined “mental illness” would automatically satisfy the mitigating circumstance of “extreme mental or emotional disturbance” (People v. Crews, 1988). The statutory definition of “mental illness” in this jurisdiction specified “a substantial disorder of thought, mood or behavior which afflicted the person at the time of the commission of the offense and which impaired that person's judgment, but not to the extent [of meeting the insanity defense test]” (People v. Crews, 1988). The Court found that the GBMI finding would not automatically qualify as a mitigating factor, although this decision might have been different had the later mitigator of “reduced mental capacity” been in effect. In any case, this is one reason that GBMI is not generally seen as an especially desirable outcome for the defense, as it does not guarantee avoidance of the death penalty. Nonetheless, guilt-phase opinions and testimony by neuropsychiatrists do remain relevant and important at the sentencing phase, whether they are ultimately effective in mitigating the sentence or not.

9 | ETHICAL CONSIDERATIONS

As mentioned, public support for the death penalty in the United States is currently on the wane, with only 28 states still retaining the penalty as one option, down from 37 at the time of Gregg v. Georgia (1976). The frequency of death verdicts and executions has decreased nationally, and although the data are less clear regarding the proportion of cases in which the prosecution seeks the death penalty, this appears to be lower as well. Nonetheless, the newer scientific insights and applications offered by neuropsychiatry remain relevant to the process. Individual forensic practitioners vary in their perceptions and opinions regarding the morality, fairness, and effectiveness of the death penalty (Beck, 1993; Halpern et al., 2004), but whatever their personal convictions are, it is important to emphasize that the fundamental duty in this context is to serve the legal process. Personal beliefs or ideology about the death penalty should not play a role. The expert witness is not the decider of the issues at stake, but a source of information and expertise to assist those who do decide and carry out the law's verdict. The practitioner in capital proceedings is of course aware that the penalty process may lead to the death of the defendant, but his or her findings may as well be instrumental in saving the accused from the penalty via testimony regarding the range of issues that affect the outcome. These include, as discussed, potential categorical exemption based on mental state, capacity, culpability or age at the time of the offense, varying degrees of mitigation, or lack of competency at any juncture of the process that would at the least serve to suspend the final reckoning.

Concerns about mental health treatment for condemned inmates, particularly involuntary treatment, tends to generate the sharpest ethical dilemmas, but these are not relevant to the neuropsychiatrist serving as an expert witness. The participation of medical doctors in the actual execution process is officially prohibited as unethical, and is considered a violation of the Hippocratic Oath, though some doctors do continue to feel a duty to be involved, albeit anonymously (Gawande, 2006).

The neuropsychiatrist serving as an expert witness should approach the evidence in a neutral fashion, and present all findings, both the “good” and the “bad,” to the retaining attorney or court so that “just” and appropriate handling of the case by the legal system can be facilitated. Working within this role is certainly not for everyone, and it is very important to be aware of and guard against personal biases that could affect the gathering or presentation of neuropsychiatric information. However, it is important to realize that abandonment of forensic participation in the capital process (so long as it remains legal) only risks leaving this important task to the less competent and least principled.

Abstract

The neuropsychiatric contribution to capital sentencing proceedings has grown substantially in recent decades as the consideration of neurological and psychiatric factors in criminal behavior has been increasingly accepted as relevant to the quest for justice. This review article will focus on the legal theories underlying neuropsychiatric input into capital sentencing decisions, as well as some of the investigative techniques and resulting data which may be offered by forensic neuropsychiatrists in this context. The death penalty is unique in its severity and irreversibility, as the courts, including the U.S. Supreme Court, have noted repeatedly. “Death is different,” and the recognition of this has generated a set of court decisions and statutes pertinent specifically to capital proceedings, both procedural and substantive.

Summary

This review examines the legal theories behind neuropsychiatric involvement in capital sentencing, exploring how neurological and psychiatric factors are increasingly viewed as relevant to the pursuit of justice. The article discusses the history of capital punishment in the United States, highlighting the shift in public opinion and the Supreme Court's landmark decisions on the issue. It delves into the concepts of mitigation and aggravation, and how neuropsychiatric expertise can be used to assess risk and provide evidence relevant to sentencing.

2 | A BRIEF “MODERN” HISTORY OF CAPITAL PUNISHMENT IN THE U.S.

The Furman v. Georgia (1972) decision marked a turning point in capital punishment in the United States. The ruling invalidated existing death penalty statutes due to their lack of guidance for juries, leading to a moratorium on executions nationwide. In response, states revised their statutes, introducing aggravating and mitigating factors to guide jury decisions. This shift aimed to address concerns about arbitrariness and ensure that sentences were individualized to the offense and offender.

3 | MITIGATION, AGGRAVATION AND RISK ASSESSMENT

Forensic psychiatrists commonly address mitigating factors related to mental state and psychopathology, although the role of mental health experts in assessing aggravating factors is less frequent. The relevance of neuropsychiatric evidence in these contexts is a subject of ongoing debate, with some arguing for its minimal impact while others anticipate a transformative effect on legal attitudes and outcomes. Despite this debate, forensic psychiatrists are increasingly involved in mitigation evaluations, particularly in capital cases where the stakes are high.

4 | THE EVIDENTIARY LATITUDE OF THE SENTENCING PROCESS

Generally, there are few constraints on the evidence presented in the sentencing phase of a trial, especially for the defense. While pre-trial and trial evidence admissibility tests are often contentious, courts typically allow a wider range of defense evidence at sentencing. This evidentiary latitude is particularly relevant in capital cases, where defendants are entitled to present mitigating information regardless of statutory limitations.

5 | THE CATEGORICALLY EXCLUDED

The U.S. Supreme Court has ruled that individuals with intellectual disabilities and juvenile offenders are categorically exempt from the death penalty, citing the 8th Amendment's prohibition against cruel and unusual punishment. The Court's reasoning emphasizes the reduced culpability of these individuals, acknowledging that they are less likely to commit the most serious adult criminal conduct. These decisions reflect shifting societal standards of decency and overruled previous precedents that permitted capital punishment for these groups.

6 | NEUROPSYCHIATRY AND CAPITAL SENTENCING FOR INTELLECTUALLY DISABLED OFFENDERS

Neuropsychiatry has the potential to play a significant role in capital sentencing for individuals with intellectual disabilities, as the Atkins v. Virginia (2002) decision left the definition of intellectual disability to forensic mental health professionals. The Court's reliance on clinical definitions set forth by the American Association on Intellectual and Developmental Disabilities (AAIDD) and the American Psychiatric Association (APA) underscores the importance of neuropsychiatric expertise in this area.

7 | CASE EXAMPLE

The case of AW illustrates the complex interplay between neuropsychiatric evidence and legal proceedings. AW, a young man with a history of abuse and diagnosed with several neurodevelopmental disorders, was found guilty of multiple murders and sentenced to death despite the presentation of uncontroverted neuropsychiatric evidence suggesting diminished capacity for impulse control and social judgment.

8 | DISTINCTION BETWEEN MR/ID AND MENTALLY ILL DEFENDANTS

The legal treatment of individuals with intellectual disabilities in capital cases is often contrasted with the approach to mentally ill offenders. While intellectually disabled individuals may be categorically exempt from the death penalty, mentally ill offenders must rely on individual defenses, such as insanity or incompetence. These defenses can slow or halt the legal process, but they do not guarantee exemption from the death penalty.

9 | ETHICAL CONSIDERATIONS

While public support for the death penalty is declining, the role of neuropsychiatry in capital cases remains relevant. Forensic practitioners are ethically bound to serve the legal process, presenting evidence in a neutral fashion and avoiding personal biases that could affect their findings. However, ethical concerns remain regarding the role of mental health professionals in the execution process and the potential for involuntary treatment of condemned inmates.

Abstract

The neuropsychiatric contribution to capital sentencing proceedings has grown substantially in recent decades as the consideration of neurological and psychiatric factors in criminal behavior has been increasingly accepted as relevant to the quest for justice. This review article will focus on the legal theories underlying neuropsychiatric input into capital sentencing decisions, as well as some of the investigative techniques and resulting data which may be offered by forensic neuropsychiatrists in this context. The death penalty is unique in its severity and irreversibility, as the courts, including the U.S. Supreme Court, have noted repeatedly. “Death is different,” and the recognition of this has generated a set of court decisions and statutes pertinent specifically to capital proceedings, both procedural and substantive.

Summary

This review article examines the legal theories that support neuropsychiatric input into capital sentencing decisions, along with investigative techniques and resulting data that forensic neuropsychiatrists may use.

1 | INTRODUCTION

The neuropsychiatric contribution to capital sentencing proceedings has grown significantly in recent decades, as the consideration of neurological and psychiatric factors in criminal behavior has become increasingly accepted as relevant to the quest for justice. This article will explore the legal theories underlying neuropsychiatric input into capital sentencing decisions, as well as some of the investigative techniques and resulting data which may be offered by forensic neuropsychiatrists in this context.

2 | A BRIEF “MODERN” HISTORY OF CAPITAL PUNISHMENT IN THE U.S.

The modern history of capital punishment in the United States begins with the U.S. Supreme Court's Furman decision in 1972. Furman v. Georgia was brought at a time when 40 of the 50 states still had laws permitting the death penalty, although public support for the penalty was at an historic low point. Similar polling a generation later indicated 80%-plus in favor of capital punishment as an available option, a turn-about of stunning size and rapidity. Today, public support for the penalty is dropping again, based in part on science-aided revelations of false convictions.

3 | MITIGATION, AGGRAVATION AND RISK ASSESSMENT

Forensic psychiatrists have commonly been asked to address mitigating issues related to mental state and psychopathology. Aggravating factors have been less frequently addressed, although forensic mental health experts have offered or been challenged to offer opinions on these as well. Mental health disorders and deficiencies are a major feature of the list of mitigating factors in almost all states. The relevance of neuropsychiatric opinion to these mitigating considerations is a question that is part of the more general debate on the relevance of increasingly sophisticated biologically-based evidence to the law's essentially moralistic questions about responsibility/accountability.

4 | THE EVIDENTIARY LATITUDE OF THE SENTENCING PROCESS

There are generally very few constraints on the nature and scope of evidence that may be presented in the sentencing phase of any trial, whether capital or not, and especially for the defense. The U.S. Supreme Court decided several decades ago that all mitigating evidence in capital cases is admissible, irrespective of statutory limits, despite Justice Scalia's objection that it undid post-Furman reforms which specified what evidence juries were to consider.

5 | THE CATEGORICALLY EXCLUDED

Mentally retarded/intellectually disabled (MR/ID) and juvenile offenders who commit crimes that for others could merit the death penalty are, via the U.S. Supreme Court's interpretation of the 8 th Amendment prohibition against cruel and unusual punishment, exempt from the penalty. The issue is one of culpability, and the Court has concluded that members of these two classes are a priori less culpable than other capital offenders.

6 | NEUROPSYCHIATRY AND CAPITAL SENTENCING FOR INTELLECTUALLY DISABLED OFFENDERS

There is significant potential for expansion of neuropsychiatry's role in capital sentencing of MR/ID offenders, since the Court's ruling in Atkins essentially left the definition of this class up to forensic mental health professionals by deferring to the states' legislatures the details of implementing its holding. The AAIDD and APA definitions make reference to substantial deficits in intellectual and adaptive functioning across several critical skills areas, with age of onset often identified as a third and less important “prong.”

7 | CASE EXAMPLE

AW is a 22-year old AA male defendant charged with three counts of first-degree murder, with the special circumstance of multiple murders making him eligible for the death penalty. The killings occurred in the context of an emotional argument with his girlfriend and her mother during which he felt attacked and belittled. He reported having dissociative symptoms during this argument (felt that he was “outside his body”), and described how he went to his vehicle, retrieved a pistol, and returned to the house where he shot and killed all the occupants.

8 | DISTINCTION BETWEEN MR/ID AND MENTALLY ILL DEFENDANTS

The law's treatment of MR/ID capital offenders is often contrasted with the approach to mentally ill offenders, with concerns expressed about unfair discrimination since mentally ill capital offenders as a class are not also exempt from the death penalty. One reason for this may be that, although the intellectually disabled are certainly not a homogeneous class, the mentally ill are even less so.

9 | ETHICAL CONSIDERATIONS

As mentioned, public support for the death penalty in the United States is currently on the wane. The frequency of death verdicts and executions has decreased nationally. Nonetheless, the newer scientific insights and applications offered by neuropsychiatry remain relevant to the process. Individual forensic practitioners vary in their perceptions and opinions regarding the morality, fairness, and effectiveness of the death penalty, but whatever their personal convictions are, it is important to emphasize that the fundamental duty in this context is to serve the legal process. The expert witness is not the decider of the issues at stake, but a source of information and expertise to assist those who do decide and carry out the law's verdict.

Abstract

The neuropsychiatric contribution to capital sentencing proceedings has grown substantially in recent decades as the consideration of neurological and psychiatric factors in criminal behavior has been increasingly accepted as relevant to the quest for justice. This review article will focus on the legal theories underlying neuropsychiatric input into capital sentencing decisions, as well as some of the investigative techniques and resulting data which may be offered by forensic neuropsychiatrists in this context. The death penalty is unique in its severity and irreversibility, as the courts, including the U.S. Supreme Court, have noted repeatedly. “Death is different,” and the recognition of this has generated a set of court decisions and statutes pertinent specifically to capital proceedings, both procedural and substantive.

Summary

Forensic neuropsychiatry plays a crucial role in capital sentencing proceedings. This article will discuss legal theories, investigative techniques, and the role of forensic neuropsychiatrists in these proceedings.

2 | A BRIEF “MODERN” HISTORY OF CAPITAL PUNISHMENT IN THE U.S.

The modern history of capital punishment in the United States began with the U.S. Supreme Court's decision in Furman v. Georgia (1972). This decision effectively invalidated the death penalty nationwide due to inconsistencies in how it was applied. As a result, many states revised their death penalty statutes to address the issues raised by Furman. The Supreme Court later upheld the revised Georgia statute in Gregg v. Georgia (1976), paving the way for the reinstatement of the death penalty in many states.

3 | MITIGATION, AGGRAVATION AND RISK ASSESSMENT

Forensic psychiatrists often evaluate mitigating factors related to mental state and psychopathology. These factors can play a crucial role in determining the sentence in a capital case. One important factor is future dangerousness, which is often assessed through violence risk assessments.

4 | THE EVIDENTIARY LATITUDE OF THE SENTENCING PROCESS

In general, there are few restrictions on the type of evidence that can be presented in the sentencing phase of a trial, especially for the defense. This includes mitigating evidence related to the defendant's mental state, which can be crucial in arguing for a lesser sentence.

5 | THE CATEGORICALLY EXCLUDED

The U.S. Supreme Court has ruled that two categories of offenders are exempt from the death penalty: individuals with intellectual disabilities (previously termed “mental retardation”) and juvenile offenders who committed their crimes before the age of 18. This exemption is based on the idea that these individuals are less culpable than other capital offenders.

6 | NEUROPSYCHIATRY AND CAPITAL SENTENCING FOR INTELLECTUALLY DISABLED OFFENDERS

The Supreme Court's decision in Atkins v. Virginia (2002) left the definition of "intellectual disability" to forensic mental health professionals. This has opened up a significant role for neuropsychiatry in assessing the intellectual functioning of individuals in capital sentencing proceedings.

7 | CASE EXAMPLE

This section presents a detailed case example of an individual facing the death penalty. The example highlights the use of neuropsychiatric evidence, including brain imaging and genetic testing, to understand the defendant's mental state and potential mitigating factors.

8 | DISTINCTION BETWEEN MR/ID AND MENTALLY ILL DEFENDANTS

The law treats individuals with intellectual disabilities differently from those who are mentally ill. While individuals with intellectual disabilities can be exempt from the death penalty based on their condition, mentally ill offenders are not categorically excluded. Mentally ill defendants may still be eligible for the death penalty, although they can argue for mitigation based on their mental state.

9 | ETHICAL CONSIDERATIONS

This section explores the ethical considerations that forensic neuropsychiatrists face when working in capital sentencing proceedings. It emphasizes the importance of objectivity and neutrality in presenting evidence and avoiding personal biases that could affect the outcome of the case.

Abstract

The neuropsychiatric contribution to capital sentencing proceedings has grown substantially in recent decades as the consideration of neurological and psychiatric factors in criminal behavior has been increasingly accepted as relevant to the quest for justice. This review article will focus on the legal theories underlying neuropsychiatric input into capital sentencing decisions, as well as some of the investigative techniques and resulting data which may be offered by forensic neuropsychiatrists in this context. The death penalty is unique in its severity and irreversibility, as the courts, including the U.S. Supreme Court, have noted repeatedly. “Death is different,” and the recognition of this has generated a set of court decisions and statutes pertinent specifically to capital proceedings, both procedural and substantive.

Summary

This article talks about how psychiatrists can help with deciding if someone should get the death penalty. They look at if someone has a mental illness or disability that might make them less responsible for their crimes.

2 | A BRIEF “MODERN” HISTORY OF CAPITAL PUNISHMENT IN THE U.S.

The death penalty in the United States has been debated for many years. In the 1970s, the Supreme Court ruled that the way the death penalty was being used was unfair. The Court said that the death penalty could only be used if there were specific reasons to use it, like if the crime was very serious or if the person who did it was a danger to others.

3 | MITIGATION, AGGRAVATION AND RISK ASSESSMENT

Psychiatrists can help decide if someone should get the death penalty by looking at the things that made the person commit the crime and if they are likely to commit crimes again. Some things that might make the person less likely to commit crimes again are if they have a mental illness or if they were abused as a child.

4 | THE EVIDENTIARY LATITUDE OF THE SENTENCING PROCESS

The law allows for a lot of different types of evidence to be used when deciding if someone should get the death penalty. This can include evidence about the person's mental state, their background, and their chances of committing more crimes.

5 | THE CATEGORICALLY EXCLUDED

The Supreme Court has ruled that people with intellectual disabilities and people who were under 18 when they committed a crime cannot get the death penalty. They said that these people are less responsible for their actions and that the death penalty would be too harsh for them.

6 | NEUROPSYCHIATRY AND CAPITAL SENTENCING FOR INTELLECTUALLY DISABLED OFFENDERS

Psychiatrists can help decide if someone has an intellectual disability. They can look at how well the person does on tests and how well they can take care of themselves.

7 | CASE EXAMPLE

This is an example of a case where a man killed three people. He had a history of violence and mental health problems. He also had some brain problems that might have made him more likely to be violent. The jury decided that he should get the death penalty, even though there was evidence that he had brain problems.

8 | DISTINCTION BETWEEN MR/ID AND MENTALLY ILL DEFENDANTS

People with intellectual disabilities and people with mental illnesses are treated differently by the law. People with mental illnesses can still get the death penalty, but people with intellectual disabilities cannot.

9 | ETHICAL CONSIDERATIONS

Psychiatrists who work on death penalty cases have to be careful to be fair and impartial. They should not let their own personal beliefs about the death penalty affect their work. They should also be aware of the ethical issues involved in working on cases where someone might be sentenced to death.

Highlights