CHEYENNE - A lawyer for a man sentenced to life in prison last year for the 1986 murder of a Casper woman asked the Wyoming Supreme Court on Thursday to rule that his client didn't get a fair trial.

Jeffrey Lynn Smith, 46, was convicted in the death of Tammy Dively, a 25-year-old single mother from Casper whose body was found along a roadside.

Prosecutors say Smith hit Dively in the head and ran her over with his truck. They say they found DNA evidence from her body that tied Smith to the crime.

The Supreme Court heard arguments on Smith's appeal Thursday at the Little America Hotel in Cheyenne, site of the annual meeting of the Wyoming State Bar.

Authorities interviewed Smith soon after Dively was found but didn't charge him until 2006. Three years after Dively's death, Smith was arrested for first-degree sexual assault for breaking into the home of a 58-year-old Casper woman and raping her. He pleaded guilty and went to prison until 2001.

Dively was a native of Bedford, Pa. She worked at the Casper College cafeteria and had lived in Casper for about six years when she was killed. She had a daughter who was 7 years old at the time.

Lawyer Michael H. Reese, representing Smith, argued Thursday that trial judge Keith G. Kautz of Natrona County violated Smith's rights when he limited Smith's original defense lawyer from presenting information about other people police had suspected in the case.

"This is literally a cold case that took 20 years to develop," Reese told the court. Reese said Smith has never confessed in the Dively case and always maintained his innocence.

Reese said the DNA evidence proves only that Smith and Dively had sex, not that he killed her. He argued it violated Smith's constitutional rights for a prosecutor to tell the jury that he had refused to take a DNA test.

"He cannot be compelled to testify against himself, and that's what's happening here," Reese said. He said that if Smith had provided a DNA sample, prosecutors could have used it against him. Reese argued that made it improper for prosecutors to tell the jury that Smith had refused to provide such a sample.

Assistant Attorney General Graham Smith, no relation to the defendant, said Kautz was correct not to allow the jury to hear information about two other men who had been considered suspects. Graham Smith said the statements were unsubstantiated.

Graham Smith told the justices that defendant Smith had repeatedly denied to investigators that he had known Dively.

"Despite his repeated denials of ever having known Ms. Dively, the sperm that was in her body was a positive match to the appellant's," Graham Smith said.

The court will issue a written ruling in the case later.