The convicted killer whose case prompted the U.S. Supreme Court to abolish the death penalty for the mentally retarded will not himself benefit, as a jury on Friday ruled he was not retarded.

After nearly 13 hours of deliberation, a York County Circuit Court jury concluded that Daryl Renard Atkins, 27, who was condemned to death for kidnapping, robbing and shooting a young airman in 1996, is not legally mentally retarded and is therefore eligible for execution.

The Supreme Court's June 2002 ruling in Atkins's case prompted courts in several states, including Mississippi, North Carolina and Nevada, to spare the lives of several mentally retarded murderers by commuting their sentences to life in prison. But the court did not decide Atkins's fate. Instead, justices left it to each state to define mental retardation -- and to a Virginia jury to decide whether Atkins fell within that definition.

"It's ironic, but as a legal matter, this was always a possibility," said Robert D. Dinerstein, an American University law professor.

The trial, the first of its kind in Virginia, illustrated the subtleties and complexities that jurors, judges and attorneys nationwide face as they carry out the Supreme Court ruling. The justices held that because of disabilities in reasoning and judgment, mentally retarded criminals should not be subject to the ultimate punishment. Such defendants have a diminished "moral culpability" and may have difficulty assisting in their own defense, the court said.

During seven days of testimony, jurors -- whose sole task was to determine whether Atkins is mentally retarded -- did not learn details about the slaying of Eric Nesbitt, 21, or even hear his name.

Instead, they heard from psychologists who administered a battery of IQ and other tests and examined Atkins's school and prison records. They also relied on the testimony of family, friends and teachers who were asked to recall the most mundane details of Atkins's daily life. Was he able to cook chicken? Drive a car? Mow the lawn? Dress himself appropriately? Write rap lyrics?

In Virginia, lawmakers have defined a mentally retarded offender as someone with an IQ below 70 who has "significant limitations in adaptive behavior" that were evident before age 18. Atkins has scored 59, 67, 74 and 76 on IQ tests, according to testimony.

When the verdict was announced, Atkins turned to his family, blew a kiss and made a peace sign. His mother, Elvira Bullock, sobbed. On the other side of the small courtroom, Mary Sloan, Nesbitt's mother, leaned back, visibly relieved that her son's killer will return to death row. Neither family would comment.

Circuit Court Judge Prentis Smiley Jr. immediately set a Dec. 2 execution date.

York County's top prosecutor, Eileen M. Addison, who twice convinced other juries that Atkins deserved the death penalty, said she had never doubted that Atkins knew right from wrong. Drug abuse, laziness and a bad attitude were to blame for Atkins's poor grades in school and problems in life, she indicated.

"We've never disagreed that he is probably a slow learner and he is not of high intelligence, but that is not the same as mentally retarded," Addison said. "I do agree with the Supreme Court's decision, but this was the wrong case."

Atkins's attorneys, who said they will appeal the ruling, said their client's disability does not excuse his crimes. But they said a death sentence is not fair punishment for a man they say reads at a fifth-grade level, can't cook basic meals, struggled to play Monopoly and was called a "retard" by his grade-school classmates.

"It's a tragedy," said Richard Burr, one of Atkins's attorneys. "The question was whether he had mental retardation. We established he did. The people in this community rejected it, and we don't know why."

Relatives testified that Atkins, who flunked second grade, had developmental problems as an infant and took longer than other children to sit up on his own and talk. As a 14-year-old, he played Power Rangers with his young nephews, joining them as an equal, one aunt testified.

But Lorraine Batchelor, who taught Atkins at an alternative school, said she saw a teenager who struggled because he came late to class and didn't try to complete his work. Batchelor testified that Atkins blamed drugs for his disinterest and that there was "no indication whatsoever that he was incapable."

Thomas G. Walker, a constitutional law professor at Emory University who has written about the Atkins case, said the trial underscores the difficulties of such cases. Jurors faced contradictory expert-witness testimony and sifted through how Atkins carried out the simplest of tasks. Jurors were left to decide whether a defendant's actions are motivated by aptitude, attitude or circumstance.

"The challenge is to extrapolate from these kinds of activities and try to determine whether the standards of mental retardation have been met," said Walker, who was in the courtroom for several days of testimony.

For example, jurors learned that Atkins, when interrupted during a meal at prison, placed his soup bowl in a sink containing some hot water to keep it warm. Prosecutors portrayed it as a clever solution for a man with no access to a kitchen. But a defense expert countered that Atkins didn't seem to understand that the water soon would cool and that his fix was only temporary.

In August 1996, according to court records, Atkins and a friend, William A. Jones, were out after a day of drinking when they spotted Nesbitt, an Air Force mechanic from Upstate New York stationed at Langley Air Force Base, outside a 7-Eleven in Hampton. The pair abducted Nesbitt at gunpoint, forced him to withdraw $200 from a bank machine and drove him to a field, where he was shot eight times.

Both men claimed the other was the shooter. In a deal with prosecutors, Jones was given a life sentence in return for testifying against Atkins.

Although the jury learned nothing about Nesbitt's slaying, future juries will not work in a similar void. Under Virginia law, defendants claiming mental retardation would go to trial, and, if convicted, the same jury would decide whether the defendants' claims were true.

Defendants in Virginia must prove mental retardation by a preponderance of the evidence, a less-rigorous standard than that used to determine guilt.

Joseph Migliozzi Jr., left, Mark Olive and Richard Burr, right, sit with Daryl Atkins in a courtroom in Yorktown. Atkins's execution was set for Dec. 2.