A few phrases have been stitched into Raymond Gonzales' brain so deeply they roll off his tongue.

David Hunt was the "the enforcer" and Richard Thompson the "diplomat," he said. John Riggins "put up some sort of scuffle" and Hunt "settled him down pretty quick," with a bash to the head. Ask him again and he'll repeat that David Hunt's wife, Suellen, went along with the ride but she was "skittish" and she never saw the bodies.

Those are the lines he's been repeating for 25 years, and he repeated them again Tuesday as a star witness in the defense of Richard Joseph Hirschfield, who is on trial for murder in the Dec. 20, 1980, bludgeon-and-slash killings of Riggins and his girlfriend and fellow UC Davis student, Sabrina Gonsalves.

Gonzales, now 63, was an undercover police operative used by Sacramento law enforcement agencies for 18 years in assorted drug, burglary and firearms investigations.

In the year after the Riggins and Gonsalves killings, Gonzales came forward and told his handlers he had information on who he thought did it – namely, David Hunt, his former brother-in-law.

Seven years later, Sacramento law enforcement lent him to a Davis police detective, Fred Turner, who had been assigned to kick the cold case around. Turner and Sacramento County sheriff's Lt. Ray Biondi sent Gonzales down to Los Angeles, to the Hotel Cecil off Skid Row, to introduce himself to Thompson, Hunt's old "road dog" from their robbery days.

Gonzales got the room next to Thompson's, bought him a few drinks and struck up a conversation in which he said Thompson related the details of the students' slayings.

Under questioning from Hirschfield lawyer Linda Parisi, Gonzales told a Sacramento Superior Court jury how he introduced himself to Thompson with a fabricated story about how he wanted to break the then-incarcerated Hunt out of prison. Having gained Thompson's trust, he testified Thompson told him how he and Hunt came across the 18-year-old kids at the Lucky's market in Davis and how he sweet-talked them into the clutches of Hunt on the way to their deaths.

"He was pretty much open," Gonzales testified, in describing Thompson's demeanor. "He was pretty relaxed. We drank a couple beers at the bar. He was pretty mellow when he talked about the murders."

Gonzales couldn't get into what he and the defense claim was the reason for the killings. Hunt, their theory goes, was the half-brother of Gerald Gallego, the late serial sex-slave murderer who had just been arrested for the killing of two Sacramento State students, and Hunt wanted to pull off a copy-cat murder to make it look like whoever did it was still at large.

Judge Michael W. Sweet ruled out any references to Gallego in the Hirschfield trial as irrelevant because no evidence directly ties the Riggins and Gonsalves killings to him.

The theory satisfied the Yolo County District Attorney's Office to file murder charges on the Hunts, Thompson and one other defendant, but it fell apart when DNA on a semen-stained blanket in Riggins' van excluded those defendants and in 2002 came back to what a state Department of Justice criminalist described as a one-in-240-trillion hit on Hirschfield.

Against those odds, Gonzales testified he had been equipped with a tape recorder for the July 14, 1987, conversation where he said Thompson laid the details of murder out to him. Somehow the recording device failed, making his credibility the bulwark of Hirschfield's third-party-culpability defense.

"I'm not lying about nothing," he testified at the end of his direct examination, leaning back in his blue-denim shirt and black jeans with no belt, his left hand on his hip and his right arm stretched casually over the right arm of the witness chair. "You could give me a polygraph test."

Deputy District Attorney Dawn Bladet instead sought to impeach Gonzales with multiple inconsistencies between his testimony Tuesday and his sworn statements during the Yolo County preliminary hearing on the so-called "Hunt Group."

Gonzales also admitted to Bladet he once "had a little problem" with methamphetamine and that "I had my issues with the drink" around the time of his conversation with Thompson.

Gonzales once testified he had as many as 16 beers the day of Thompson's admissions; he said Tuesday, "I was never at the point where I was intoxicated."

He confirmed he went to investigators with Hunt's name because he was interested in a $30,000 reward. He also once testified that Hunt "did dirt" to his sister, he admitted Tuesday, but he never told police about his brother-in-law problem before they hooked him up with Thompson. "So what?" Gonzales testified.

Bladet used a transcript from a July 20, 1987, Gonzales conversation with Thompson, portions of which were taped. Sections of the transcript Bladet displayed on the courtroom's overhead projector mostly depicted the now-deceased Thompson expressing confusion or wondering what Gonzales was talking about when he made reference to the murders.

At one point, the transcript quotes Gonzales as lying to Thompson that Hunt is concerned his wife might talk to police about the Davis killings. "The what?" Thompson replied. When Gonzales asked Thompson how he lured the victims to their deaths, Thompson said, "What?"

While the transcript doesn't contain any admissions by Thompson, Gonzales, under additional questioning by Parisi, said it doesn't have him denying anything, either.

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