A man who heard screams in the apartment hallway where Diane Whipple was mauled to death by two dogs last year testified Thursday he thought someone was being raped or that it was a domestic dispute.

The defense called him to bolster its theory that defendant Marjorie Knoller tried to stop the dogs, a possibility raised by another neighbor. But the witness, David Kuenzi, declined to say the voice of the screamer was any different from the voice saying "stop."

"I presumed it was the same woman saying, 'Stop, please stop.' It seemed the woman was no longer screaming but was begging for mercy. It was truly terrifying," he said.

Knoller is accused of second-degree murder, involuntary manslaughter and having a mischievous dog that killed a person. Knoller's husband, Robert Noel, faces the latter two charges.

Kuenzi's testimony followed a series of witnesses who portrayed the two Presa Canarios involved in the Jan. 26, 2001, mauling death as gentle. Also Thursday, Judge James Warren said he would look into whether a defense attorney violated a gag order by attacking the credibility of Whipple's domestic partner during a TV interview.

The trial was moved to Los Angeles because of extensive publicity.

Kuenzi was a visitor to San Francisco and intended to stay with a friend in the building, but got there before the friend arrived home.

He testified the screams he heard began as a shrill, high-pitched sound which ultimately became a whimper, and then there was a voice saying, "Stop, please stop."

"It was from someone being physically assaulted," he said.

Kuenzi said he was afraid to enter the floor where the attack was occurring and uncertain what to do. He said he had to go down to the lobby to get reception on his cell phone.

Another defense witness, Dave Neville, told the jury that two weeks after the killing he saw two dogs that looked like Presa Canarios being walked five blocks from the apartment where Whipple died. Neville said the dogs' owner gave him an unfriendly look and he turned away.

Knoller's attorney, Nedra Ruiz, later said she called the witness to try to show there might have been other dogs in the neighborhood that scared passers-by. She suggested that those who reported scary encounters with the defendants' dogs, Bane and Hera, may have been mistaken.

Other defense witnesses included kennel owners and friends of the defendants who described petting and playing with the big dogs without being threatened.

Kim Boyd, a legal client of the couple, said she visited their apartment, accompanied Noel down an elevator with one dog and saw a building tenant pass without incident.

On cross-examination, Assistant District Attorney Jim Hammer stressed that Boyd saw the dogs in their home environment for only a few minutes and could not say what they did at other times.

"The issue legally is whether Ms. Knoller had knowledge these dogs were dangerous. But the law does not require that they were always vicious," Hammer said outside court.

Meanwhile, the judge said a hearing on whether Ruiz violated his gag order will be held May 17.

Warren, who barred attorneys from commenting on the credibility of witnesses, was sent a transcript of a Fox News program interview in which Ruiz said Whipple's partner was "exaggerating or lying" about Whipple being bitten previously.

Interviewer Greta Van Susteren then asked: "Are you saying that Sharon lied about it? Is that what you're saying?" Ruiz replied: "Yes, I am."

"My client has the right to have her side told," Ruiz said outside court.