Intellectual Disability and the Death Penalty

Defining Intellectual Disabilities
The Courts and Executing Defendants with Intellectual Disabilities
Continuing Issues with Executing Individuals with Intellectual Disabilities
The Issue of Intellectual Disability in the Anthony Porter Case
Related Links

Defining Intellectual Disabilities

In 2002, the U.S. Supreme Court in Atkins v. Virginia held it is unconstitutional to execute defendants with "mental retardation," a term then used for individuals now identified as persons with intellectual disabilities. However, legal questions surrounding this issue remain unresolved. The Court in Atkins left the definition and method of determining intellectual disability up to individual states.

The American Association on Intellectual and Developmental Disabilities (AAIDD), an organization of clinicians and other intellectual disabilities professionals, uses the following guidelines to determine whether a person has an intellectual disability:

• An IQ test is used to determine a person’s level of intelligence. A person may have an intellectual disability if his or her IQ score measures in the bottom two percent of the population. The AAIDD measures this as an IQ score at or below 70, although people with an IQ of up to 75 may still have intellectual disabilities.
• Another indication of intellectual disability is determined by a clinical evaluation that measures deficits in the person’s adaptive behavior and his or her functional level of intelligence. This evaluation identifies real-life skills the person does not have, or real-life tasks the person cannot do, because of his or her intellectual disability. These deficiencies in behavior may be found in communication, self-care, or functional academics. In essence, the mental health examiner tries to understand how successfully the person is able to apply his or her fundamental level of intelligence, as determined by an IQ test, in the real world.
• The age of onset is the final criterion for determining whether a person has an intellectual disability. The AAIDD states that a subject must display signs of an intellectual disability before age 18 in order to be considered intellectually disabled. Typically, a person will manifest an intellectual disability at birth or during early childhood.

The Courts and Executing Defendants with Intellectual Disabilities

One of the first discussions of intellectual disabilities and the death penalty occurred in 1978 when the U.S. Supreme Court decided Lockett v. Ohio (1978). The Court held that evidence of a defendant’s mental disabilities is admissible during the sentencing hearing as a mitigating factor. However, the ruling did not forbid the execution of people with intellectual disabilities.

In 1989, the question of whether individuals with intellectual disabilities could be executed was brought before the Supreme Court in Penry v. Lynaugh (1989). The Court decided that although intellectual disability is a factor that may lessen a defendant’s culpability for a capital offense, the Eighth Amendment did not preclude the execution of a person based on his or her intellectual disability alone. The Court also decided that as long as a jury or judge was able to consider a defendant’s intellectual disability when imposing sentence, the determination of whether death is the appropriate punishment could be made on a case-by-case basis. The Penry decision was significant in two ways. First, the ruling affirmed that intellectual disability is so relevant to the level of an offender’s culpability that states cannot refuse to allow the jury to consider it as a mitigating factor. Second, the Court said there was, at that time, “insufficient evidence of a national consensus against executing [individuals with intellectual disabilities] convicted of capital offenses for [the Justices] to conclude that it is categorically prohibited by the Eighth Amendment.”

Between 1989 and 2002, disability advocacy groups mobilized efforts to ban the execution of individuals with intellectual disabilities. Additionally, national opinion polls indicated lack of support for executing individuals with intellectual disabilities. For example, in the late 1980s, when 71% of the population supported the use of death penalty, only about 25% favored executing individuals with intellectual disabilities (Ellsworth & Gross, "Social Science and the Evolving Standards of Death Penalty Law," 2008). After 18 states banned the practice through legislation, in 2002 the Supreme Court revisited the issue in Atkins v. Virginia, overturned Penry v. Lynaugh, and determined that the "legislative judgment reflects a much broader social and professional consensus" that executing individuals with intellectual disabilities was an excessive punishment not in accord with our standards of decency. Justice Stevens, delivering the opinion of the Court, wrote:

Mentally retarded persons frequently know the difference between right and wrong and are competent to stand trial, but, by definition, they have diminished capacities to understand and process information, to communicate, to abstract from mistakes and learn from experience, to engage in logical reasoning, to control impulses, and to understand others' reactions. Their deficiencies do not warrant an exemption from criminal sanctions, but diminish their personal culpability.

The Court doubted that the justifications underpinning the death penalty – retribution and deterrence – applied to intellectually disabled offenders. Justice Stevens wrote,

As to retribution, the severity of the appropriate punishment necessarily depends on the offender's culpability. If the culpability of the average murderer [that is, a murderer whose crime involves no special aggravating circumstances] is insufficient to justify imposition of death, the lesser culpability of the mentally retarded offender surely does not merit that form of retribution. As to deterrence, the same cognitive and behavioral impairments that make mentally retarded defendants less morally culpable also make it less likely that they can process the information of the possibility of execution as a penalty and, as a result, control their conduct based upon that information.

The Court cited the higher probability of inaccurate factual determinations of guilt and individual culpability due to the increased potential that defendants with intellectual disabilities would “unwittingly confess to crimes they did not commit.” For example, Earl Washington, who had an IQ of 69, faced execution after confessing to a crime he did not commit. In 1983, police convinced Washington to make a statement concerning the 1982 rape and murder of a woman in Culpepper, VA. The statements were used against him, and in 1984 he was convicted and sentenced to death. Sixteen years later, DNA tests confirmed that Washington was innocent and he received an absolute pardon.

The Atkins opinion also suggested that “[m]entally retarded defendants may be less able to give meaningful assistance to their counsel and are typically poor witnesses, and their demeanor may create an unwarranted impression of lack of remorse for their crimes.”

Continuing Issues with Executing Individuals with Intellectual Disabilities

According to Dr. Denis Keyes, who has published several articles regarding disability issues, at least 46 known “mentally retarded” persons have been executed since 1976. Two of those executions occurred after Atkins v. Virginia was decided. Controversy persists because Atkins did not provide a definition of intellectual disability, leaving the issue to the states. Although most states use some variation of AAIDD’s definition, there is still ambiguity in whether a capital defendant has an intellectual disability, how this disability should be determined, and whether a judge or jury should make the determination.

Most states now opt to have a judge decide whether a capital defendant has an intellectual disability, probably because this procedure is thought to be less expensive and less complicated than a jury trial. Additionally, most states make this decision in a hearing before trial, thereby saving the time and resources involved in a lengthy capital trial. Of course, an adequate determination of intellectual disability in pretrial proceedings requires that defense counsel recognize early in their investigation of a case the need to test for intellectual disabilities. Most states require an IQ test, a personal history chronicling intellectual disability developments, and an expert evaluation to substantiate a claim of intellectual disabilities - which require time and resources that may be unavailable to state-appointed counsel or public defenders. Continuing ambiguities in the process of determining intellectual disabilities contribute to the risk of arbitrary implementation of the death penalty.

The Issue of Intellectual Disability in the Anthony Porter Case

Anthony Porter was sentenced to death on September 9, 1983. After a series of appeals, Porter was scheduled to die on September 23, 1998, but just 50 hours before his execution the Illinois Supreme Court granted a stay to examine his mental capacity. Porter had an IQ of 51, well below the threshold commonly used to deem a person “mentally retarded.” Although at the time Illinois law did not forbid executing individuals with intellectual disabilities, it did forbid executing anyone who was mentally incapable of comprehending the punishment he was about to receive. The court was not confident Porter could meet this test. Similarly, the Due Process Clause of the federal Constitution, as interpreted by Ford v. Wainwright (1986), would not have barred Porter’s execution simply because of his intellectual disabilities, but might have barred it if these disabilities prevented him from understanding he was being put to death as a punishment for his crime. Ultimately Porter was exonerated of murder. The evidence of his innocence emerged while his execution was stayed to examine his competency to be executed. Judicial concern about his intellectual disabilities indirectly saved his life, and it remains an open question whether those disabilities contributed to his wrongful conviction because of handicaps that defendants with intellectual disabilities face in criminal trials, as the Supreme Court later recognized in Atkins.

The concern about Porter’s mental capacity raises multiple issues about punishment in our justice system today. Understanding the implications of one’s crime and punishment is an issue at the time of the crime, at trial and sentencing, and at the time of execution.

Questions for Further Analysis:

• Why should limited intellectual functioning be considered a mitigating factor in capital cases?
• Since defendants with intellectual disabilities are to be excluded from the death penalty, how should intellectual disabilities be defined? Who should determine intellectual disability? What should the role of experts be and how should they be chosen?
• How would courts treat an adult who suffered severe intellectually disability after a traumatic head injury?
• In light of the problems associated with the definition of intellectual disabilities, should federal legislation be passed to ensure uniform application of Atkins? Is it acceptable that a federal constitutional law requirement restricting the permissible application of the death penalty be administered differently from state to state?
• Why was the Supreme Court concerned with public opinion sentiment in deciding whether executing people with intellectual disabilities constitutes a cruel and punishment under the Eighth Amendment?

Related Links

Mental Illness and the Death Penalty
Mitigation in Capital Cases
The Case of Anthony Porter