Harris Seeks to Have Sentence Overturned : Death Penalty: The killer of two San Diego teen-agers has seen his case progress further toward execution than that of any other convict on California’s Death Row.

In a legal brief filed Friday, Robert Alton Harris has urged the California Supreme Court to overturn his death sentence, arguing that he has changed for the better in prison.

Hoping to put off California’s first execution since 1967, Harris, convicted of the murders of two San Diego teen-age boys, said it would be cruel and unusual punishment to kill him now that he has changed.

Harris, whose case has progressed further through the court system than that of any of the more than 200 men on California’s Death Row, also contended that the lengthy delay since he was condemned to die--nearing 11 years--has violated his rights and warrants a new sentence.

Aside from those two claims, the nine other reasons detailed in the 180-page brief were mostly technical requests for relief, Harris’ lead attorney, Charles Sevilla of San Diego, said Friday. A few, however, were responses to the denial last September by the U.S. 9th Circuit Court of Appeals in San Francisco of the earlier appeal Harris had filed, Sevilla said.

If all of Harris’ appeals are rejected, some death penalty experts have said there is a chance he could be die in San Quentin’s gas chamber by the end of the year.

The U.S. Supreme Court is scheduled to consider this month whether to hear Harris’ earlier appeal, Sevilla said. However, the brief filed Friday will begin yet another round of appeals for Harris, as the case works its way through the state and federal courts.

The U.S. Supreme Court already has upheld key parts of Harris’ 1979 trial, making it unlikely that the court will review his case, prosecutors have said. The California Supreme Court, meanwhile, affirmed Harris’ death sentence about 10 years ago.

Harris was arrested July 5, 1978, by San Diego Police Officer Steve Baker, who did not know that earlier in the day Harris had killed Baker’s son, Michael, and Michael’s friend, John Mayeski.

The 16-year-old boys had been eating their lunches in the parking lot of a Jack-in-the-Box in northern San Diego when Harris kidnaped them at gunpoint in a scheme to steal their car and use it in a bank robbery.

He ordered them to drive to a canyon near Miramar Reservoir, where he killed them. Later, he ate their lunch.

In the brief filed Friday, Harris argued that it violates his rights to kill him now that he has become what one regular visitor called an “affable, extremely friendly and obviously well-liked” prisoner.

Harris included in the brief 21 sworn statements from friends, other inmates and even guards at San Quentin saying he has mellowed in prison.

Among the other reasons Harris said he should not be put to death is “newly discovered” evidence of “mental disorders” that Harris claimed have affected him but he did not know about when he was sentenced.

The four “disorders”--including a claim of post-traumatic stress disorder that does not involve military service--obviously weren’t presented at the trial and require neurological attention, Harris contended.

Sevilla filed the brief Friday with an intermediate state appeal court in San Diego.