The United States is the only country whose jurisprudence expressly permits such executions and which carries them out with distressing frequency, as documented in our recent report, Beyond Reason: The Death Penalty and Offenders with Mental Retardation.
An adult with mental retardation who commits a murder should be held legally accountable, assuming the retardation is not so profound as to render him or her incompetent to stand trial. But the death penalty is always disproportionate to the moral culpability of the mentally retarded. The mentally retarded have limited abilities to learn, reason, plan, understand, judge, and discriminate. They have trouble understanding abstract concepts, including moral ones. They have a truncated capacity to think about intended actions, to consider their possible consequences, and to exercise mature control over their conduct. Given their limited cognitive abilities, the mentally retarded should never be placed in the category of the most culpable offenders for whom the death penalty is ostensibly reserved.
People with mental retardation are also uniquely vulnerable to miscarriages of justice in criminal trials. They are susceptible to suggestion, eager to please, and readily acquiesce to other adults or authority figures, including the police. These characteristics lead them to waive their rights to remain silent and, in some cases, even to make false confessions. Beyond Reason includes a number of cases in which men with mental retardation have confessed to crimes they did not commit and have spent years on death row before their innocence was ultimately established. Indeed, just last week a mentally retarded man who confessed to and was convicted of six murders was released from prison in Florida after DNA tests showed he could not have committed the crimes.
In 1989, in Penry v. Lynaugh, the U.S. Supreme Court in a five to four decision ruled that executing the mentally retarded did not violate the Eighth Amendment to the U.S. Constitution. Justice O'Connor's majority opinion relied heavily on the absence of a national consensus against such executions for her conclusion that U.S. standards of decency had not evolved enough to warrant a constitutional prohibition. At the time, only two states forbade the death penalty for the mentally retarded. Since then, fifteen states and the federal government have enacted legislation that prohibits such executions. Bills with similar measures have passed the Missouri and Connecticut legislatures and are awaiting the governors' signatures. Public opinion polls consistently show a preponderance of the American people, even those who otherwise support the death penalty, believes that executing the mentally retarded is wrong. They recognize, as does the rest of the world, that accountability and public safety can be secured through punishment short of death and that executing people of limited cognitive abilities is not necessary to advance the putative goal of deterrence.
This spring, the Supreme Court agreed to hear the case of McCarver v. North Carolina. Petitioner Ernest McCarver, a man with mental retardation, is asking the Court to overturn the Penry decision and to rule that the constitution prohibits the execution of mentally retarded offenders. In light of the number of mentally retarded individuals who continue to be sentenced to death in the U.S., such a ruling is needed to guarantee this barbaric practice is banned from the nation. A brief from the solicitor general urging a constitutional prohibition against executing the retarded would be an invaluable contribution to the outcome of the case.
Again, we commend you for placing your administration on record as opposing the execution of mentally retarded offenders. However terrible the crimes committed by a person with mental retardation, his or her execution is unacceptable in a civilized nation.