Former neighbors of a couple charged in the mauling death of a neighbor told harrowing stories in court Thursday about confrontations with the defendants and their two huge dogs.

The half-dozen witnesses followed testimony by a state investigator who said defendants Marjorie Knoller and Robert Noel worked with members of a white supremacist prison gang to raise dangerous guard dogs.

Noel and his wife, Knoller, both lawyers, are charged in the Jan. 26, 2001, mauling of their neighbor Diane Whipple by two Presa Canario dogs they kept in their San Francisco apartment. The trial was moved to Los Angeles due to extensive publicity in San Francisco.

Among witnesses describing encounters with the dogs was Neil Bardack, who testified that in September 2000, when Knoller was walking one of the dogs, the dog clamped its teeth around Bardack's three-legged Sheltie and put "a death grip on her back."

Bardack said he took the dog for treatment the next day and found she had a puncture wound, but he never reported it to authorities.

"I let it pass and moved on," he said. "My dog healed."

But when Whipple's death was reported on the news, he said, he realized it involved the same dog and the same woman.

Knoller, 46, who was walking one of the dogs when Whipple was attacked, is charged with second-degree murder, involuntary manslaughter and having a mischievous animal that killed a human being. She faces up to 15 years in prison if convicted.

Noel, 60, faces the latter two charges and up to four years in prison if convicted.

The couple's defense lawyers say both were unaware that the dogs were dangerous. Knoller's attorney Nedra Ruiz says her client risked her own life trying to save Whipple from the dogs. Noel's lawyer, Bruce Hotchkiss, says his client was not present during the attack and is not responsible.

Testifying in the trial Thursday, David Moser said he was bitten on the buttocks by one of the couple's dogs as he moved belongings out of the apartment building where he and the defendants lived.

"Mr. Noel looked and said, 'Hmm. Interesting,' and he just walked away and left me sitting in the lobby," Moser testified. "I was kind of in shock and it was disturbing — the reaction. They didn't come over. They didn't apologize."

Also during Thursday's testimony, Devan Hawkes, an employee of the state Corrections Department who investigates gangs, cited letters found at the couple's home and in the cells of two inmates belonging to the Aryan Brotherhood prison gang.

Letters from Noel showed active involvement in a "Dog O' War" business, Hawkes said.

Jurors were shown enlarged portions of letters in which Noel appeared to encourage Pelican Bay State Prison inmate Paul "Cornfed" Schneider to try to escape and said that if he and Knoller were present they would help.

"I would want to make it clear," Noel wrote, "... If you went for the door, all she and I would do is wave you goodbye and wish you godspeed."

Hawkes also identified a letter from Noel that named and pinpointed the location of an inmate who had dropped out of the Aryan Brotherhood.

"There is a potential danger," Hawkes said. Noel "is identifying the location of a potential witness, and the potential is that bodily harm could come to this witness."

Hawkes said Schneider and another inmate worked with Noel and Knoller on a business to raise Presa Canarios with the Aryan Brotherhood for use as guard dogs.

Prosecutor Jim Hammer showed jurors invoices for books ordered by the prisoners — among them Gladiator Dogs, Fighting Dog Breeds and Manstopper: Training a Canine Guardian.

During cross-examination, defense attorneys questioned the assertion that the defendants were gang associates.

"Isn't it possible that a person could help an individual who is a member of a gang without intending to benefit the gang?" Ruiz asked.

"I suppose so," Hawkes said.

After the testimony on Thursday, the trial was recessed until Monday.