LOS ANGELES (AP) — The first defense witness in the Phil Spector murder trial, a noted forensic expert on gunshot wounds, testified Tuesday that Lana Clarkson committed suicide by shooting herself in the mouth at the record producer's mansion.

Dr. Vincent DiMaio, a physician with a specialty in forensic medicine, was asked by attorney Christopher Plourd for his conclusion about how the actress died.

"She died of a self-inflicted wound," said DiMaio. "There is no objective scientific evidence that anyone else held the gun. "

He said the proof was in gunshot residue and blood on her hands as well as the nature of the wound.

"She's got blood on her hands, gunshot residue on her hands, an intra-oral wound. Ninety-nine percent, it's suicide," DiMaio said.

Clarkson, 40, was a struggling actress who met Spector, now 67, at her job as a House of Blues hostess. According to testimony, she went to Spector's mansion for a drink when she got off work and a few hours later was dead from a single bullet fired into her mouth. Her body was found in a chair in a foyer, one hand resting on her purse and a bloody revolver at her feet.

Prosecutors claim Spector shot her; the defense says she committed suicide.