Until last year, Daryl Atkins was just another convict on Virginia's death row.
But then, his lawyers filed an appeal asking the US Supreme Court to overturn his death sentence. They made the request not because their client is innocent of any involvement in the 1996 murder for which he was convicted, but because he may not be intelligent enough to fully appreciate the depth of his wrongdoing and the severity of the punishment he faces.
With an IQ of 59, Mr. Atkins has been diagnosed as being mildly mentally retarded. Prosecutors in Virginia dispute that diagnosis and insist he fully understands the difference between right and wrong.
Today, Atkins's case will be heard before the high court, where the justices are being asked to decide whether capital punishment for convicted murderers who are mentally retarded violates the Eighth Amendment's ban on cruel and unusual punishment.
It is potentially a major decision. A victory for Atkins could establish a constitutional precedent that would block the death penalty whenever a convicted murderer is diagnosed as being mentally retarded (regardless of the individual facts of a case). Instead, the maximum penalty such defendants would face is life in prison without parole.
It is unclear how many of the nation's 3,700 death-row inmates might ultimately be designated as mentally retarded.
"Mental retardation profoundly limits a defendant's personal culpability for his or her actions," writes Robert Lee in Atkins's brief to the justices. Mr. Lee also argues that evolving standards of decency in the US have resulted in the emergence of a national consensus against execution of the mentally retarded.
Lawyers for the state of Virginia counter that mentally retarded individuals do not all possess the same level of intellectual ability. Many have the mental capacity to plan, premeditate, and deliberate with specific intent to kill, they say.
In the crime that led to Atkins's murder conviction, he and an associate, William Jones, abducted a US Air Force airman named Eric Nesbitt from the parking lot of a convenience store in Hampton, Va., in August 1996.
At gunpoint, they took $60 out of Mr. Nesbitt's wallet, then drove him in his own truck to the automated teller machine at his bank, where they forced him to withdraw another $200. Then they drove him to a remote location where he begged for his life. He was shot eight times. The two men stole Nesbitt's truck and left him beside the road, where he died.
A jury found that Atkins was the triggerman and sentenced him to death. Mr. Jones, who testified against Atkins as part of a deal with prosecutors, received a sentence of life in prison.
Atkins's lawyers argue that their client's mental retardation made it easy for police and prosecutors to maneuver him into a death sentence.
Prosecutors insist Atkins is the triggerman and was smart enough to know that it was wrong to carjack someone, commit armed robbery, and then shoot and kill them.
"Society's legitimate interests in deterrence and retribution are served by the execution of mentally retarded offenders who have the ability to plan and carry out a capital murder," writes Pamela Rumpz, an assistant attorney general in Virginia, in her brief to the court.
Ms. Rumpz adds that no national consensus has emerged on the issue. "A full 29 of the 38 states which authorize the death penalty permit it to be imposed on at least some, if not all, mentally retarded capital murderers," she says. "Society has not clearly set its face against such punishment, and, thus, it cannot be said to be cruel and unusual."
Others say momentum is building against such executions. Within the past year, five states have enacted restrictions on executing the mentally retarded, and two weeks ago, Virginia's own Senate unanimously adopted a similar measure. The state's General Assembly has yet to act on it.
"Every state that has affirmatively passed legislation on the subject has said no death penalty for someone with mental retardation," says Ron Tabak, co-chair of the American Bar Association's death-penalty committee, which filed a friend-of-the-court brief supporting Atkins.
The last time the high court examined this issue, in 1989, the justices ruled that the execution of mentally retarded defendants did not amount to cruel and unusual punishment.
But the court instructed prosecutors that mentally retarded defendants must receive a fair trial, including giving the jury the opportunity to assess an individual's mental retardation as a mitigating factor prior to deciding whether to sentence the individual to death.
A year earlier, the Supreme Court ruled that executing defendants younger than 16 amounts to cruel and unusual punishment because children have a lower level of culpability than adults. Death-penalty opponents ask why the same constitutional analysis shouldn't apply to a mentally retarded adult with the intellectual development of someone 15 or younger.
Says Lee in his brief: "As with children, the moral reasoning of individuals with mental retardation is only partially developed."