Convicted serial killer Billy Glaze's appeal for innocence died with him, a Hennepin County judge has ruled.

Glaze, convicted of the murders of three women in Minneapolis in the 1980s, had long maintained that he didn't commit the crimes, and attorneys with the Minnesota Innocence Project were trying to free him last year based on new DNA evidence that they contend pointed to another man.

But amid their appeal, Glaze, 72, fell ill with lung cancer and died on Dec. 22. He never got a new trial, which his attorneys were advocating he receive.

Prosecutors in Hennepin County moved quickly to have Glaze's latest arguments to the court dismissed, saying the case was moot after Glaze died. They had remained confident that they had the right man and argued that a new trial wasn't needed.

Innocence Project attorneys argued that not only was Glaze's reputation at stake, but so was the public's interest in learning whether the justice system worked fairly in his case. Perhaps more important, they argued, was the question of whether the person responsible for the killings is still free. They claimed that no physical evidence linked Glaze to the murders but that DNA testing of sperm collected from one victim's body excluded Glaze but matched the other man; DNA testing of a cigarette butt that had been collected near another victim's body did the same.

Testing had continued during Glaze's appeal.

In a nine-page ruling, Judge Toddrick Barnette found that attorneys for Glaze hadn't yet proven his innocence with the evidence they introduced. For that reason, there was no "live controversy" to be resolved, the judge found.

While Barnette agreed with Glaze's attorneys that there is an important public interest in exonerating innocent people and ensuring that prosecutions are conducted fairly, without evidence to prove Glaze's innocence, analyzing mistakes and raising questions about criminal justice system reforms aren't necessary, the judge wrote.

"Finally, nothing in the record supports a finding that [Glaze] was actually innocent or that his conviction was wrongful," the ruling said.

In 1989, a jury found Glaze guilty of first- and second-degree murder in the bludgeoning deaths of Kathy Bullman, 19; Angeline Whitebird-Sweet, 26; and Angela Green, 21. All were found nude or mostly nude with their bodies positioned in ways that suggested they were victims of a serial killer. The cases prompted intense media attention and public outcry, including allegations that police hadn't been aggressive in investigating crimes against American Indians.

Hennepin County Attorney Mike Freeman said in a statement Thursday that he was satisfied with the decision: "We cooperated with the Minnesota Innocence Project to review the case. But in the end, the evidence was overwhelming that Glaze was the killer and he rightfully spent the rest of his life in prison."

Minnesota Innocence Project Legal Director Julie Jonas said Glaze's team of attorneys was disappointed in the ruling. "We believed with the DNA testing that was in existence at the time of his death, we proved Glaze's innocence," Jonas said.

Defense attorney Ed Magarian said they plan to appeal.