SAN JOSE, Calif. (AP) _ Other defendants have erupted in court, shouted obscenities at judges and even turned on their attorneys. But rarely, if ever, has one uttered the kind of malevolent insult Richard Allen Davis spewed before being sentenced to die for killing Polly Klaas.

The courtroom accusation: that the 12-year-old girl had been molested by her father, Marc Klaas.

``It's extremely unusual that a defendant, a convicted defendant who is present for sentencing, takes the opportunity to throw ... emotional acid in the face of the bereaved survivor,'' said Robert Pugsley of Southwestern University School of Law.

``Most defendants don't say anything, except to plead for mercy,'' said former Massachusetts prosecutor Tom Hoopes, now in private practice in Boston. ``This guy is just a manipulator to the end.''

Emotion is no stranger to the courtroom.

William Kirkpatrick Jr., one of Davis' new colleagues on San Quentin's death row, had to be shackled during sentencing in August 1984 and was threatened with a gag after he yelled an obscenity at the judge.

Last year in Dayton Beach, Fla., a 35-year-old man convicted of robbing and murdering his 70-year-old landlady was gagged after he interrupted the judge with declarations of innocence.

Richard Ramirez, Southern California's ``Night Stalker'' serial killer, was hauled from a court hearing in August 1989 after he yelled that his trial was a joke and cursed the judge.

What made Davis' statement on Thursday unusual was that it was aimed at someone outside the system _ a bereaved parent.

``It exceeds the bounds of decency that we expect even from people convicted of the kind of vicious crime for which he was sentenced to death,'' Pugsley said Friday.

``It made the hair on the back of my neck stand up,'' concurred Kelly Rudiger, executive director of the Doris Tate Crime Victim's Bureau.

Davis, 42, was convicted in June of killing Polly after kidnapping her as she played with two other girls in her bedroom in Petaluma, a small city about 45 miles north of San Francisco.

The jury found the ``special circumstances,'' of robbery, kidnapping, burglary and attempting a lewd act on a child, meaning a punishment of death or life in prison without possibility of parole. On Aug. 5, jurors chose death.

At Thursday's formal sentencing, defense attorneys had been expected to ask the judge for life.

Instead, only Davis addressed the court, embarking on a long list of complaints.

The insult came when he started talking about the one charge he had always denied _ that he tried to sexually molest Polly. Davis said the reason he knew he didn't commit that crime was because Polly had told him: ``Just don't do me like my dad.''

Klaas shouted an obscenity and lunged at Davis. Klaas was restrained and hustled out as his mother, B.J., broke into heart-rending sobs. Others in the courtroom gasped and groaned.

Outside the courtroom, Klaas called the allegation a ``vile and sinister and evil act.''

Prosecutor Greg Jacobs said no such claim had been made during the case and there was no evidence to support it.

Jacobs delivered a short argument in favor of death, and Superior Court Judge Thomas Hastings confirmed the sentence, telling Davis _ now inmate No. D11903 _ he had made the traumatic decision ``very easy.''

Some victims' rights groups questioned whether the incident indicates a need for more strictures on defendants.

Rudiger of the Tate bureau, named for the mother of Manson Family victim Sharon Tate, is considering a bid to deny defendants the right to speak at the sentencing if, like Davis, they do not testify.

But Peter Keane, chief attorney at the San Francisco Public Defender's office, said it would be ``completely unrealistic'' to try to silence them.

Throughout the trial, which began April 16, there was open animosity between Klaas, an outspoken advocate for child victims, and Davis.

Still, no one had expected Davis' revenge.

``The Klaas family did not deserve that extra stab in the back,'' Rudiger said.