An Orange County Superior Court judge found enough evidence Thursday to move forward with a case against a Costa Mesa woman who was accused of lying to police during a murder investigation involving her then-fiance.

But prosecutors may still have a "hard time" proving that Rachel Buffett, 25, intentionally misled investigators to help Daniel Wozniak, 28, also of Costa Mesa, avoid getting caught, said Judge Kazuharu Makino.

Toward the end of the hours-long preliminary hearing, Makino questioned whether Buffett would lie to police to prevent Wozniak's conviction even after Wozniak told investigators that he killed their Costa Mesa neighbor and their neighbor's tutor.

Still, he said, after hearing testimony from three Costa Mesa police detectives who worked on the case, "I think the evidence is sufficient."

Buffett faces up to three felony charges of accessory after the fact for her alleged involvement following the murders of Samuel Herr, 26, of Costa Mesa, and Juri "Julie" Kibuishi, 23, of Irvine.

"Common sense is not too common," Buffett said after the proceedings. "The judge appeared to demonstrate common sense, but the legal process is tedious and my lawyer said this was to be expected. I'm sad to see the pain drawn out for the victims' families."

Buffett's family, as well as the families of Herr and Kibuishi, sat through the hearing, during which many of the grizzly details of the case were retold. Kibuishi's and Herr's parents sat together in the front row of the gallery, comforting each other.

"We're just relieved that it's going forward," Herr's father, Steve Herr, said.

Kibuishi's mother, June Kibuishi, said it was the first time she'd heard some of those details presented in court.

After more than two years, she said, the pain of losing her daughter is still fresh.

"It's like having your heart ripped out of your body," she said, gesturing to her chest.

Buffett is due back in court for an arraignment Dec. 26.

jill.cowan@latimes.com

Twitter: @jillcowan