Seven more witnesses testified about the chain of custody on key evidence in the Richard Joseph Hirschfield murder trial, but the real action in court Tuesday took place outside the presence of the jury.

Hirschfield's defense team again asked to be allowed to present evidence to the Sacramento Superior Court jury that four other people had been charged with the killings of UC Davis students John Riggins and Sabrina Gonsalves some 32 years ago.

And once again, Judge Michael W. Sweet precluded Hirschfield's lawyers from making mention of the Yolo County prosecution.

Before the trial began, Sweet denied much of the defense effort to present evidence of third-party culpability in the Dec. 20, 1980, slayings of the 18-year-old college sweethearts.

Yes, the judge said, the defense could present evidence that investigators looked into other suspects – David Hunt, his wife Suellen Hunt and former prison buddies Richard Thompson and Douglas Lanier. But the judge said any reference to Yolo prosecutors having actually charged the four, in a case that crumbled when DNA testing excluded the members of the so-called "Hunt Group," would only confuse the Hirschfield jury.

Hirschfield, 63, is accused of slashing and bludgeoning Riggins and Gonsalves to death during the course of a sexual assault on the young woman. He faces the death penalty if he is convicted.

Two of the seven witnesses called to the stand Tuesday were former Davis Police Detective Fred P. Turner and onetime Yolo County district attorney's investigator John Haynes.

Their testimony was restricted to their handling of evidence that ultimately produced a DNA profile that prosecutors say matched Hirschfield's. The most important among the items of evidence was a blanket found in Riggins' van that contained four semen stains.

Turner and Haynes were proponents of a theory of murder that led to the Yolo County prosecution of the Hunt Group. Sweet ordered the two former detectives back to court Oct. 15, when they will be called as defense witnesses when Hirschfield's lawyers put on their own case.

Earlier in the trial, Deputy District Attorney Dawn Bladet sought to have an arrest warrant issued on Turner when he did not respond to a subpoena to appear as a witness in the trial.

Sweet issued the warrant Sept. 6, but stayed it pending Turner's court appearance. Bladet asked Tuesday that the warrant be recalled.

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