Conviction Is Upheld in Mysterious Murder : Justice: Appeal court upholds killer’s sentence in slaying of teen-age co-worker. Motive remains a mystery.

Mark Alan Radke, convicted of first-degree murder in the brutal 1988 killing of a Mira Mesa teen-ager, was fairly tried and properly sentenced to the maximum term possible, 25 years to life, a state appeal court in San Diego ruled Tuesday.

Rejecting Radke’s claim that evidence against him was illegally obtained by police, the 4th District Court of Appeal said Tuesday the evidence showed Radke planned and executed the killing of Jeffrey Rudiger, 17, who had worked with Radke at a Scripps Ranch pizza restaurant.

Rudiger disappeared after work on the night of Jan. 21, 1988. His beaten body was found the next day in a Scripps Ranch alley. Radke was convicted of murder two years later.

The conviction did not, however, resolve the puzzling case, which has been dogged by the question of whether a second person was involved in the killing. A San Diego Superior Court jury could not decide whether Radke or a mystery accomplice wielded the murder weapon, and the 4th District court did not take up the issue.

Radke, now 25, who is behind bars at Folsom State Prison, has never spoken on the issue. He did not testify at his trial.

His defense lawyer, San Diego attorney Douglas C. Brown, said Tuesday too many unanswered questions remain in what he called a “disturbing” case. He promised further appeals to the California Supreme Court and, if necessary, to the U.S. Supreme Court.

Prosecutors at the state attorney general’s office could not be reached Tuesday for comment.

Both Radke and Rudiger worked at a Chuck E. Cheese restaurant in Scripps Ranch, near where Rudiger’s body was found Jan. 22, 1988, the morning after he disappeared.

When he was discovered, Rudiger was clad only in underwear and a T-shirt. He was wearing handcuffs, had been bludgeoned on the head with a blunt object and had cuts on his body.

Radke was arrested after Rudiger’s friends told police he and Radke were working together on a secret project.

Before the case ever made it to trial, it generated three separate appeals over whether police had acted properly in detaining Radke for questioning after a traffic stop.

At one point, a state appellate court ruled police were overzealous and had violated Radke’s constitutional rights by placing him in handcuffs and drawing a revolver. That decision would have made virtually all evidence in the case off-limits to prosecutors.

Later, though, San Diego Superior Court Judge Charles R. Hayes ruled officers on the case had probable cause--or a “strong suspicion”--to arrest Radke before they ever saw him, meaning all the evidence officers found later was obtained legally.

The 4th District court upheld that ruling Tuesday, saying Radke’s rights had not been violated.

The pretrial appeals were unusual, Justice Daniel J. Kremer said. But it was eminently reasonable for police, who already had been talking to friends and family and suspected that Radke may have been involved in the killing, to have searched him when they stopped him, Kremer said.

The search turned up blood spots that matched Rudiger’s blood type in Radke’s car trunk, in the wheel wells of his recently cleaned car and on his jacket, according to testimony at the trial.

Kremer said a motive for the killing remained uncertain. But the manner of the slaying--it appeared Rudiger was hit 26 times with a tire iron or similar object--showed that it had been deliberate, violent attack rightly found to be first-degree murder, Kremer said.

Justices Richard D. Huffman and Charles W. Froehlich Jr. joined the ruling.