Music producer Phil Spector was found guilty Monday of second-degree murder in the February 2003 shooting death of actress Lana Clarkson.
Jurors also found Spector personally used the firearm while committing the crime at his Alhambra mansion. Sentencing has been set for May 29.
Second-degree murder carries a penalty of 15 years to life in prison. The firearm enhancement adds three, four or 10 years in prison, according to the district attorney's office.
The judge denied bail and Spector, wearing a fire-engine red tie and pocket square, was taken into custody after the verdict was announced. He also wore a "Barack Obama Rocks" button on his left suit lapel.
Spector and his wife entered the courtroom at about 2 p.m., and the verdict was read at about 15 minutes later. His son and daughter were seated next to him at the counsel's table.
Spector's wife, Rachelle, cried as the decision was announced. Spector showed no reaction as his attorney rubbed his client's left shoulder.
Members of the Clarkson family, including her mother and sister, also were in the courtroom.
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"This is why we do this job," said prosecutor Alan Jackson. "If there's a wrong, we can attempt to try to right it. Today is when the Clarkson family gets their justice."
As of Monday morning, the jury had spent about 30 hours discussing the case over eight days since March 26.
Spector, 69, was charged with murder in the Feb. 3, 2003, shooting death of the 40-year-old actress and House of Blues VIP hostess at his mansion in Alhambra. He claims she shot herself with his gun.
"We thought the case was about what the scientific and physical evidence showed," said Spector's attorney, Doron Weinberg. "We thought it showed he did not commit the crime. We thought that should have been sufficient."
Weinberg said he believed the case was swayed by the judge's erroneous rulings, particularly one that allowed five women from Spector's past to testify. He said it would be the basis for appeal and a request for a new trial.
Still, he added that Spector took the verdict "very stoically. He wanted to know what is next."
Los Angeles Superior Court Judge Larry Paul Fidler told jurors that they could consider convicting Spector of involuntary manslaughter instead of second-degree murder.
The option of involuntary manslaughter was not given in Spector's first trial. That jury deadlocked 10-2 on the second-degree murder charge in September 2007, with the majority voting in favor of convicting him.
"This entire jury took this so seriously," the forewoman said in an interview room after the verdict was read. "I don't think there could have been another set of people who would listen to everything, review everything. It is a painful decision. Until somebody is in our shoes, you have no idea. It's tough to be on a jury. You're talking about another human being. We all have people we love. You try to evaluate another human being and it's difficult."
She said there was not a single piece of evidence that convinced the jury of Spector's guilt. "Everybody was completely neutral," she said, until they went through the evidence "piece, by piece, by piece."
Spector, renowned in music circles for the "Wall of Sound" technique he invented in the 1960s and used in his work with the Beatles and other groups, had been free on $1 million bail posted shortly after his arrest.
Clarkson, who was best known for her starring role in the 1985 Roger Corman cult hit "Barbarian Queen," had bit parts on dozens of television shows and in a few well-known movies, such as 1982's "Fast Times at Ridgemont High."
Spector had long lived in seclusion at his suburban Alhambra "castle." He was out on the town in Hollywood when he met Clarkson on Feb. 3, 2003, at the House of Blues.
The tall, blond actress, recently turned 40 and unable to find acting work, had taken a job as a hostess. When the club closed in the wee hours, she accepted a chauffeured ride to Spector's home for a drink. Three hours later, she was dead.
Spector's chauffeur, the key witness, said he heard a gunshot, then saw Spector emerge holding a gun and heard him say: "I think I killed somebody."
Defense attorney Doron Weinberg disputed whether the chauffeur remembered the words accurately. In closing arguments, Weinberg listed 14 points of forensic evidence including blood spatter, gunshot residue and DNA, which he said were proof of a self-inflicted wound.
"It's very difficult to put a gun in somebody's mouth," he said.
"Every single fact says this is a self-inflicted gunshot wound," Weinberg argued. "How do you ignore it? How do you say this could have been a homicide?"
But prosecutors portrayed Spector as a dangerous man who became a "demonic maniac" when he drank and had a history of threatening women with guns. They also contended blood spatter evidence proved that Clarkson could not have shot herself.
As in the first trial, they presented testimony from five women who told of being threatened by a drunken Spector, even held hostage in his home, with a gun pointed at them and threats of death if they tried to leave. The parallels with the night Clarkson died were chilling even if the stories were very old -- 31 years in one instance.
Clarkson's mother and sister sat through both trials and Spector's young wife sat across the courtroom from them.