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A death row inmate whose case led to the Supreme Court's ban on executing the mentally retarded was found mentally competent by a Virginia jury Friday. A judge immediately scheduled his execution for December.

Daryl Atkins (search), 27, flashed a peace sign to his family and blew a kiss as he was led from the courtroom after the verdict was read.

Three years ago, Atkins' case had led to the landmark U.S. Supreme Court (search) ruling that declared executing the mentally retarded to be unconstitutional. The court, however, left it up to states to determine whether inmates are retarded.

The Virginia jury deliberated for 13 hours over two days before determining Atkins was not retarded.

If the jury had deemed Atkins retarded, he would have been spared execution and instead sentenced to life in prison for the robbery and slaying of an Air Force enlisted man over beer money.

York County prosecutor Eileen Addison said she agrees with the Supreme Court's ruling on executing the mental retarded, but she said Atkins' was "the wrong case."

"We never disagreed that he was probably a slow learner," she said. "That's not the same as being mentally retarded."

Atkins' lawyers maintained they had established their client's mental retardation.

"People in this community rejected that. We don't know why," attorney Richard Burr said.

During a court proceeding that the judge said was unique in judicial history, defense lawyers had portrayed Atkins' mental abilities as so limited he was cut from the football team because he couldn't understand the plays.

The prosecution blamed his poor performance in school on the use of drugs and alcohol, and said the claim of mental retardation was a ploy to avoid execution.

Both sides called expert witnesses who disagreed on whether Atkins fell into the category of mentally retarded.

An IQ of 70 or less by the age of 18 is required to be considered mentally retarded in Virginia, which also takes into account social skills and the ability to care for oneself. Atkins had scores of 59, 67, 74 and 76 on IQ tests, but they were given when he was older than 18.

Atkins was 18 when he and William Jones killed Airman 1st Class Eric Nesbitt (search), 21. Nesbitt was abducted outside a convenience store, forced to withdraw money from an automated teller machine and driven to a desolate road, where he was shot eight times.

Prosecutors said Atkins was the triggerman. A plea agreement was reached with Jones, who testified against Atkins and received a life sentence.

Atkins' case has been closely watched by civil rights activists, in part because the jury did not include any blacks and Atkins is black. The jurors declined to comment after the verdict was read.

Eighteen states already had laws on the books exempting the mentally retarded from execution before the Supreme Court's ruling in Atkins' case. Eight, including Virginia, have revised their laws to comply with the ruling.