Mental Retardation and the Death Penalty

September 4, 2003

On June 20, 2002, the U.S. Supreme Court ruled in Atkins v. Virginia that executing people with mental retardation violated the Eighth Amendment prohibition against cruel and unusual punishment, overruling its Penry v. Lynaugh  decision in 1989.

The difference, according to the Court, was its finding that a public consensus had emerged, demonstrating ""evolving standards against executing people with mental retardation.""

Between 1989 and 2002, sixteen states outlawed executing mentally retarded people, bringing the total to eighteen of the 38 states that have the death penalty.  The Court also looked to public opinion polls that have consistently shown support for banning executions for people with mental retardation, as well as international law and opinion that universally condemns the practice.   

The ruling means states that have the death penalty are now under a Constitutional mandate to craft legislation and other procedures to ensure that people with mental retardation are not executed. It is not an easy task.

Mental retardation is a commonly misunderstood disability.   It is defined by the American Association on Mental Retardation (AAMR) as "significantly sub-average general intellectual functioning existing concurrently with deficits in adaptive behavior and manifested during the developmental period." Three factors must be taken into account in order for a person to be classified as mentally retarded. 

First, a person must have sub-average intellectual functioning. Intelligence Quotient (I.Q.) tests are one means of determining sub-average functioning but it is important not to confuse IQ with mental retardation.  A common standard is an I.Q. of 70 or below; but numbers alone do not always determine mental retardation.

Second, a person must have difficulty coping in the everyday world. People with mental retardation, particularly in its less-severe form, are often able to be autonomous members of society, holding jobs, and living without assistance. However, they have greater difficulty than the average person in dealing with stressful situations. Their intellectual development and reasoning are limited, as is their ability to predict cause and effect.

Third, the disability must manifest itself prior to adulthood, which is usually considered age eighteen. (This third requirement makes it impossible for a defendant to ""fake"" mental retardation.)  

People with mental retardation are at a higher risk of wrongful convictions and death sentences.  They may be more likely to falsely confess to a crime because they want to please the authorities that are investigating the crime. They are less able than others to work with their lawyers to help to prepare their defense. Because of the stigma attached to mental retardation, people with this disability often become adept at hiding it, even from their lawyer, not understanding the importance of this information to the outcome of the case.  

State legislatures across the country are working to bring their laws into compliance with the Atkins decision, crafting definitions and developing processes to determine mental retardation.  

Definitions can be too limiting.  For example, some states, like Idaho, have defined mental retardation by a fixed IQ number, even though experts agree that these numbers alone do not determine mental retardation.  Under Idaho law, someone with an IQ of 71 could be executed, even if he or she otherwise qualified as mentally retarded.  

Another crucial issue is when the determination is made, and by whom.  Advocates for the mentally retarded want the decision made pre-trial, by a judge or unbiased jury, based solely on evidence of retardation.  Prosecutors in states like Virginia and Louisiana have been arguing for the decision to be made post-conviction by the same jury that found the person guilty of murder.  It is clear that a  pre-trial decision makes more sense; if a person is mentally retarded and not eligible to be executed, the state saves the hundreds of thousands of dollars associated with a death penalty prosecution.

Case Study

Earl Washington:  The case of Earl Washington is a poignant example of how those with mental retardation are more vulnerable in the criminal justice system. Washington was sentenced to death in 1983 for a crime he did not commit. Because of his mental retardation he was induced by police into confessing to the crime. DNA evidence eventually proved his innocence, but not before Washington came dangerously close to being executed. Washington spent ten years on death row and then several more years in prison before he was finally released in January of 2001.

Click here for more information on the exoneration of mentally retarded death row prisoners.

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