Hennepin County prosecutors are confident they have the right man convicted as a brutal 1980s Minneapolis serial killer, despite the findings of an inmate advocacy group casting doubt on the case through DNA evidence.

Billy Glaze, who is serving three life sentences for the high-profile murders of three American Indian women, should remain behind bars and doesn't need a new trial, prosecutors argued in court papers filed Friday afternoon. Glaze's case, they said, "is not a DNA exoneration case."

The jury saw "overwhelming evidence" of Glaze's guilt at his 1989 trial, prosecutors wrote. Glaze's own confessions before and after his conviction confirm his guilt and explain the lack of physical evidence at the scenes of the murders, they contend.

The Minnesota Innocence Project, a group dedicated to freeing innocent prisoners, is seeking a new trial for Glaze, who has spent more than 25 years behind bars for the murders. They argue there was no biological evidence linking Glaze to the crimes. New DNA tests of 39 items found at the murder scenes, including bodily fluids, clothing and other items, also found no link to Glaze, they said. Instead, the group argues, those tests implicate another man — a convicted Minnesota rapist whom they declined to identify publicly. They argued that Glaze's confessions were false.

Glaze's lawyers said in phone interviews Friday that they were disappointed with the state's response.

The filing "continues to rely upon discredited evidence," said Ed Magarian, a partner at the firm of Dorsey & Whitney who is working on the case with the Innocence Project.

A jury found Glaze, now 71, guilty of first- and second-degree murder in the bludgeoning deaths of Kathy Bullman, 19, Angeline Whitebird-Sweet, 26, and Angela Green, 21. The bodies of the women were found between July 1986 and April 1987 in three locations frequented by transients in Minneapolis. All three were found nude or mostly nude with their bodies positioned in ways that suggested a serial killer. The cases prompted intense media attention and public outcry, including allegations that police hadn't been aggressive in investigating crimes against Indians.

Hennepin County Attorney Mike Freeman said in a statement Friday that the Innocence Project's evidence is "inconclusive and unpersuasive" and doesn't meet the legal standards for a new trial.

"This office, and I personally, believe in innocent until proven guilty," the statement said. "We also believe that if new evidence is found, it should be pursued and analyzed. This office followed those standards in this case and after reviewing what has been presented, we are absolutely convinced, as was the jury, that Billy Glaze is guilty."

Prosecutors argued that Glaze had an "intense hatred toward Native American women" and a "fantasy to sexually mutilate them." They outlined a list of statements that witnesses said he'd made to that effect.

Confessions and DNA

Glaze's conviction was based largely on testimony from witnesses and jail inmates. Prosecutors also presented a note that Glaze had purportedly written in jail saying, "I killed them. I was mad at them."

Innocence Project attorneys say the witness testimony was unreliable and the physical evidence — including the note — didn't prove him guilty.

In 2009, DNA testing of sperm collected from Green excluded Glaze, but when Innocence Project attorneys persuaded the FBI to run the DNA through a national database of millions of offenders in 2012, it came up as a match to another Minnesota man.

In April, DNA testing of a cigarette butt collected near Whitebird-Sweet's body also excluded Glaze and revealed a match to the same Minnesota man.

Innocence Project attorneys found the other man used to frequent the same establishments as the victims.

Prosecutors argued Friday that the vaginal swab from Green had DNA from two men and it can't be determined when she had sex with the man that the Innocence Project is now pointing to as a suspect.

The cigarette butt found near Whitebird-Sweet's body came from a heavily trafficked area near the American Indian Center on Franklin Avenue in Minneapolis, and contained only a partial DNA profile that cannot exclude the new suspect's father or brother, prosecutors contend. They contend the cigarette butt was old.

Attorneys for Glaze pointed out that police collected only fresh-looking, relevant evidence from the scenes. The county could exclude the relatives through DNA testing, they said.

Prosecutors claim that the request for a new trial is "just the latest in a string of blame-shifting over the years."

Prosecutors wrote that Glaze "proudly admitted" to law enforcement officers in 2004 that he had committed the murders, saying he made sure that he didn't leave evidence and didn't have sex with the victims because he had other things on his mind, specifically killing them.

Minnesota Innocence Project managing attorney Julie Ann Jonas said Glaze has an IQ of 75 and also admitted to many other murders in California that he was never connected to.

Pam Louwagie • 612-673-7102