EVERETT — Public defenders representing a man accused of two 1995 Snohomish County “cold-case” killings won a significant victory Wednesday.

Superior Court Judge Bruce Weiss ruled it would be prejudicial for Danny Ross Giles to face a single trial on both cases.

If prosecutors want to prove Giles is responsible for what happened to Patti Berry and Tracey Brazzel 19 years ago, they will have to convince separate juries, the judge said.

To do otherwise would ignore the “inherent danger” that jurors could be swayed more by emotion than evidence, Weiss said.

There is insufficient proof that the women fell victim to a “common scheme or plan” instead of two similar crimes that happened weeks apart, the judge ruled.

“The dots have not been connected,” Weiss said.

It wasn’t immediately clear Wednesday if the ruling will affect how prosecutors move forward, but it is almost certain to make it tougher for them to win convictions on both counts.

Berry, 26, worked as a dancer at Honey’s, a nude nightclub that used to be along Highway 99 north of Lynnwood. She encountered her killer on July 31, 1995, after heading home from work.

Brazzel disappeared May 27, 1995. The hairstylist, 22, was last seen at a pub south of Everett along Highway 99, according to police.

Brazzel’s body has never been found. Berry was repeatedly stabbed and dumped in the woods south of the Everett Mall.

A convicted rapist, Giles, 46, has spent much of his life cycling in an out of prison. He was not a suspect in either case until 2008, when genetic tests yielded a match, first on the steering wheel of Berry’s car and later on a spot that had been collected from the exterior of Brazzel’s vehicle.

The state crime lab calculated the statistical probability of a random DNA match to Giles in the Berry case at 1 in 580 million, and 1 in 56 quadrillion in the Brazzel case, according to court papers.

He was charged with two counts of first-degree murder in 2012.

Trial is now scheduled for September and Giles’ attorneys argued that “catastrophic prejudice” would occur if the jury heard evidence on both counts.

Neal Friedman, the county’s longest-serving public defender, argued prosecutors were trying to prop up two weak cases by offering them as a matched set.

Deputy prosecutor Craig Matheson countered that both cases were strong, just in different ways. Weiss on Wednesday said he disagreed with both sides. He characterized the evidence in the Berry case as “strong” but said the strength of the case is only “medium at best” for Brazzel. Moreover, the alleged links between the two cases were revealed to be based on theories or speculation — not facts that could be weighed by jurors, the judge said.

Weiss’ ruling means that two murder trials will need to be scheduled, both expected to last several weeks.

Matheson told the judge trying them back to back may not be possible because other cases are scheduled.

After the hearing, he said prosecutors and detectives will have to confer before deciding their next steps, including which case to bring Giles to trial on first.

No decisions are expected before next week.

Giles’ criminal record includes the 1987 rape of a woman attacked while she was using a Lynnwood tanning bed, plus a string of other crimes against women and girls starting in his teens.

By severing the murder cases, he now is at risk of amassing three “strikes,” and an automatic life sentence should he be convicted, Weiss said.

Friedman told the judge he didn’t think that likely, but Weiss said he wanted a record made that Giles fully understands his legal predicament.

After the hearing, Friedman said the judge had made the correct decision.

“It was the proper ruling based on the law and it will enable Danny to have a fair trial,” he said.

Scott North: 425-339-3431; north@heraldnet.com. Twitter: @snorthnews