A jury in Spokane, Washington convicted 65-year-old Donna Perry on Thursday of three counts of first-degree murder for the brutal killing of three prostitutes in 1990 — a decade before the transgender murderer got a sex change operation in Thailand.

Prior to rechristening himself as Donna Perry and undergoing genital mutilation in Bangkok, Perry had been a man named Douglas Perry.

Superior Court Judge Michael Price announced the verdict in court on Thursday morning, reports The Spokesman-Review, Spokane’s main newspaper.

The evidence that Perry murdered the three women — Yolanda Sapp, Kathleen Brisbois and Nickie Lowe — was substantial.

Yolanda Sapp, Kathleen Brisbois and Nickie Lowe were all found shot to death near the Spokane river just weeks apart in 1990. pic.twitter.com/kT1pfZdLnq — Lindsay Nadrich (@KREMLindsay) June 27, 2017

In 2012, Perry told investigators that “there’s a great downturn in violence” after a man has a sex change operation and, in fact, that the sex change operation was “a permanent way to control violence,” according to Spokane radio station KXLY.

Police interviewing Douglas at the time suggested that serial killers frequently don’t stop murdering.

“Douglas didn’t stop. Donna stopped it,” Perry responded, according to a police affidavit obtained by KXLY.

“I’m not going to admit I killed anybody, I didn’t. Donna has killed nobody,” Perry also told detectives.

“I don’t know if Doug did or not, it was 20 years ago and I have no idea whether he did or did not.”

Perry added that the sex change created a new attitude that was “paranoid and emotional but won’t hurt anybody.”

The murders occurred weeks apart. Police discovered the victims’ bodies naked or partially naked on the banks of the Spokane River.

DNA belonging to Perry — who dated a prostitute who had worked in the same area where the three victims worked — was found beneath one murdered woman’s fingernails, on a blanket near the location of one of the bodies and on a bottle of lubricant recovered with one of the victim’s possessions, according to The Spokesman-Review.

The big break in the case came after Perry’s DNA was entered into a national database for a 2012 conviction in Texas. That conviction was for possessing firearms as a felon, according to Spokane CBS affiliate KREM-TV.

Investigators also found the 1969 International Scout Perry owned at the time of the murders. It contained a .22 caliber cartridge which matched bullets used to kill the three prostitutes.

But wait! There’s more! In addition, a woman who had spent time in jail with Perry told investigators that Perry boasted of killing nine prostitutes (and bragged about being a contract killer).

The cellmate, a woman, told detectives Perry killed the prostitutes “because she couldn’t breed and the women had the ability to have children and they were wasting it being ‘pond scum,'” according to KXLY.

Perry, who has a notable rap sheet, was also arrested in 1988 for possession of a pipe bomb. At the time, he also owned 49 guns and 20,000 rounds of ammunition, according to The Spokesman-Review.

Despite the litany of evidence against Perry, defense attorneys complained that prosecutors had failed to establish guilt beyond a reasonable doubt.

“It’s one of those things where the jury put a lot of weight on what was said while Donna was in jail,” defense attorney Brian Whitaker told The Spokesman-Review. “That’s what this boils down to, because the physical evidence wasn’t there.”

Prosecuting attorney Sharon Hedlund expressed relief for the families of the three victims.

“We hope this gives the families some closure,” she said, according to The Spokesman-Review.

Price, the presiding judge, decided it would be a good idea to thank Perry after he read the verdict.

“Ms. Perry, I’ve appreciated all the dignity you’ve shown,” the judge told the convicted serial killer, according to the Spokane newspaper.

Perry will be sentenced on July 24. The maximum sentence is a life sentence for each murder charge.

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