A jury's conviction of Kevin Hilton for murdering his Richland landlords in 2002 was upheld Tuesday by the Washington Court of Appeals.

Hilton's attorney argued that Hilton deserved a third trial in the deaths of Larry and Josephine Ulrich because the defense did not get to present evidence that someone else killed the couple.

Lenell Nussbaum of Seattle, who represented Hilton, argued that Hilton's constitutional right to due process was violated because his trial lawyers were prevented from presenting a proper defense.

Nussbaum was unavailable Tuesday and is out of her office until Oct. 14.

Hilton rented a Mahan Avenue duplex from the couple for about six years. He twice has been found guilty of two counts of aggravated first-degree murder.

Benton County Deputy Prosecutor Terry Bloor said he was happy with the unanimous decision.

Key in the court's findings was that daughter Lisa Ulrich had absolutely nothing to do with her parents' death, Bloor said. She loved them, he added.

"I think the court of appeals hit it exactly right," he said. "Really, I think that Lisa Ulrich was treated very unfairly in this process. ... She had the tragedy of finding her parents murdered, and it was totally unfair that she was blamed."

Bloor pointed to the court's opinion, which noted the defense failed to show the jury how Lisa Ulrich would have had access to a .45-caliber gun or the rare ammunition used by Hilton. The defense did not show that she could use the weapon with the "skill of a killer."

The court also wrote there was no evidence that she returned to her parents' home that night, so Hilton's circumstantial evidence was insufficient to allow him to argue that she had a role in her parents' deaths.

"The theory that Lisa Ulrich killed her parents was completely unsupported by the facts," the opinion said.

Such a case was so weak that it would have made the defense look "desperate," the opinion concluded. Instead, the defense counsel chose to try to persuade the jury that Lisa Ulrich was biased and not credible.

Lisa Ulrich has been maligned, when there is no evidence that anyone but Hilton killed Josephine and Larry Ulrich, Bloor said.

"The opinion in here was very strong. It was unanimous," he said. "The state isn't really concerned about an additional review (by the state Supreme Court)."

Nussbaum has 30 days to petition the state Supreme Court to review the Court of Appeals decision, according to court rules.

Josephine, 67, and Larry, 72, were killed March 20, 2002.

Hilton owed $3,475 in rent and penalties to his landlords and was unemployed, except for odd jobs he did on the computer or in property maintenance for the Ulriches. Prosecutors said at the trial that Hilton became desperate when the Ulriches served him with a three-day notice to pay up or move out.

A receipt found in Larry Ulrich's hand was made out to Hilton for $3,475. Jurors cited it as key evidence in their decision.

The opinion issued Tuesday also stated that the prosecutor properly cross-examined Hilton about his ability to tailor his alibi to meet evidence from the first and second trials and that evidence from Schoonie's Rod Shop properly was admitted.

Hilton changed his testimony about what books he returned to the library March 20, what grocery store he went to that night and when he sold a Norinco .45-caliber handgun at a Walla Walla gun show, according to the opinion.

"Any one of those pieces of testimony opened up the door (to cross-examination on tailoring); in combination, they kicked the door down," according to the opinion.

Hilton has remained adamant that he is innocent and at sentencing expressed sympathy for the deaths.

Nussbaum was successful in getting Hilton's first conviction overturned because of invalid search warrants at Hilton's rental house.

That led to a second trial, which was moved to Asotin County because of extensive Tri-City media coverage. Evidence seized in the searches at Hilton's Mahan Avenue home could not be used in the second trial.

Hilton again was convicted in February 2008 after a five-week trial. The jury took seven hours to return the verdicts.

Hilton, who is serving a life sentence, is at Airway Heights Corrections Center, according to the state Department of Corrections' offender search.