Was he a hero who injected new life into a dormant murder investigation? Or was he just a blunderer who set back the search for the real killer of two UC Davis college students brutally slain 32 years ago?

Fred P. Turner came off as a bit of both Monday in his testimony in the Richard Joseph Hirschfield murder trial. He told a Sacramento Superior Court jury how he brought some heat to the cold case when he took it over in 1987. At the same time, he came under attack from a prosecutor who has repudiated Turner's efforts and blasted him on cross-examination for failing to control an operative whose work in the Dec. 20, 1980, murders of Sabrina Gonsalves and John Riggins was highly suspect.

Turner is the Davis police detective who drove 5,000 miles across nine states to make a case against four suspects who were charged – but later exonerated – for the crimes, when a DNA test on a semen-stained blanket found in Riggins' van ultimately was matched to Hirschfield, according to state Department of Justice criminalists.

Twenty-nine times during his testimony, Turner, who now lives in Washington state and was testifying as a defense witness after the prosecution rested its case earlier Monday, broke into nervous laughter while explaining his version of events to the jury. He never got a chance to say whether he still stands behind his theory of the case.

Outside court, Turner emphatically stated he still believes that his four suspects – David Hunt; his wife, Suellen Hunt; former prison buddy Richard Thompson (now deceased); and another inmate friend named Douglas Lanier – were responsible for the deaths of Riggins and Gonsalves.

"Absolutely," Turner said in an interview. As for the DNA, he said, "All it means is there were people that we did not have identified that may have been part of the same group."

Hirschfield, 63, faces the death penalty if convicted. Besides the murder charges, he faces special-circumstance allegations of murder during the course of rape, kidnap and forced oral copulation.

In their defense of Hirschfield, his lawyers have seized upon Turner's theory. It maintains that Hunt led a murder party from Arizona, Nevada and then Davis, where Riggins and Gonsalves were abducted, to Folsom Boulevard near Lake Natoma, where their bodies were dumped. Turner and the Hirschfield lawyers say the Hunt party did it to throw investigators off the track of Hunt's half-brother Gerald Gallego, the late, serial sex-slave murderer who was then in custody for the killings of Sacramento State students Craig Miller and Mary Beth Sowers.

Linda Parisi of the defense team led Turner through as much of the theory as Judge Michael W. Sweet would allow.

The retired detective told about his work with a Sacramento undercover police operative and informant Ray Gonzales, equipping him with a voice-activated tape recorder and dropping him off at the Hotel Cecil off Los Angeles' Skid Row on July 14, 1987, to try to draw a confession from Thompson, the former Hunt cellmate, about how and why the group killed the kids.

"He was a trusted informant," Turner said of Gonzales. "He had been used by law enforcement. He came well-represented as trustworthy and capable."

Turner testified he picked up Gonzales the morning after his conversation with Thompson. The operative, Turner said, "elicited remarkable information." The only problem was, none of Thompson's purported admissions showed up on tape. To compensate, Turner said he had Gonzales recount in his own recording his recollections of what Thompson had told him.

On another occasion, Turner sent Gonzales back to Thompson with a transmitter. Background noise rendered the wire useless, Turner said.

Judge Sweet allowed Turner to testify about one intriguing find – a driving trip by Hunt and his friends from their homes in Phoenix to Carson City, Nev., where the Gallego half-brother married Suellen Hunt the day that Riggins and Gonsalves disappeared. It put them within two and half hours of Davis. But that was about as much of the Gallego theory that the judge allowed the defense to enter.

Under cross-examination, Turner admitted to Deputy District Attorney Dawn Bladet that not only was the Hotel Cecil tape inaudible, but that Gonzales didn't even give him the cassette until a month after the conversation because the operative had "misplaced" it. Nor did Turner document the date he finally obtained possession of the tape.

Turner said he only worked six homicide cases in his career, that he had never been trained on the handling of informants and that he failed to document all the conversations he had with Gonzales, including the many that took place while the two drove together on the Hunt trail from California to Arizona, Utah, Colorado and Montana.

He admitted he never documented Gonzales' criminal history before sending him to see Thompson, didn't note the possible bias that might have resulted from the fact that Gonzales' sister was once married to Hunt, didn't debrief him to find out what he knew about the case and didn't check into his drug and alcohol background.

Yet Turner testified that he believed Gonzales was reliable, mostly because he showed up on time for their meetings.

"He had the gift of gab," Turner also said of Gonzales, who is scheduled to testify when the trial resumes today.

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