Dorothy Melvin was the first of four women expected to tell the jury about confrontations with Spector that the prosecution claims were similar to the scenario that led to the fatal shooting of actress Lana Clarkson in the producer's suburban Alhambra mansion more than four years ago.
The start of testimony came on the heels of defense opening statements that focused heavily on scientific evidence and assertions that the forensics will prove that Clarkson shot herself.
Attorney Linda Kenney-Baden said the defense's star witness will be science and she presented exhibits that suggested DNA would prove Clarkson also loaded the weapon.
Melvin, Rivers' assistant for 23 years, said that, after several years of occasional dating, she went to Spector's Pasadena home in 1993 and spent a pleasant evening in which he played the piano, danced with her and showed memorabilia, including a John Lennon guitar.
But she said he drank nearly a whole bottle of vodka and, at some point, disappeared. She said she woke up on a couch early the next morning and found Spector outside, pointing a handgun at her car and then at her.
At one point, she testified, "He took his right hand that was holding the revolver and smacked me on the side of the head."
She said she didn't press charges because, "I didn't want it to become a National Enquirer cover."
Early Show national correspondent Hattie Kauffman notes Melvin also described Spector as erratic, sometimes flying into rages.
"He snaps and turns on a dime, and he becomes a lunatic, and then he goes back to what he was," said Melvin.
Defense attorney Roger Rosen showed during cross-examination that Melvin and Spector continued to communicate by e-mail, mail and fax, and even saw each other a few times in subsequent years, until his arrest in the Clarkson killing. After that, she said, Spector continued to send her clippings about the case.
Rosen also displayed a number of postcards with sayings such as, "Missing you" and messages signed, "Love, Phillip."
"Phil is a very brilliant and charming man," she said as Spector sat across the room at the counsel table. "... Only, when drinking, he snaps and becomes a lunatic."
The first witness was called after the defense told the jury it will rely on an invisible witness to Clarkson's death: science.
"We have one unimpeachable witness who has no motive to lie, no memory problems, no language problems, and that witness is science," said Kenney-Baden, a lawyer whose specialty is forensic evidence.
Following co-counsel Bruce Cutler's opening attack on police procedures and women who he said would tell "tall tales" about Spector, Kenney-Baden gave jurors a course in gunshot wounds, bullet trajectories, blood spatter and what she called "the absence of evidence to prove guilt, which is proof of innocence."
"The science will tell you who did what and what happened here," she said. "The science will tell you Phil Spector did not shoot Lana Clarkson, did not hold the gun, and did not pull the trigger."
She said of the account presented in the prosecution's opening statement Wednesday: "It is a story made up by people who were not there. The science was there."
Kenney-Baden and Cutler both said forensic evidence would show Spector was not standing close enough to shoot her, that his DNA was not on the gun, and that his clothing bore no trace evidence to prove guilt.
"She was covered with GSR (gunshot residue)," the attorney said. "Phil Spector was not covered with GSR. It means he did not shoot that gun. He was too far away to get GSR on his clothes."
She said the defense will call renowned scientists including Henry Lee, Werner Spitz and Vincent DeMaio to testify.
"Science will show you her death was caused by a self-inflicted gunshot wound," said Kenney-Baden. "Science cannot tell you what was in her mind."
But she cited despairing e-mails sent by Clarkson in which she said she was going to tidy her affairs and "chuck it all because it's too much for a girl to bear."
Kenny-Baden's presentation was "detailed and compelling," Court TV correspondent Beth Karas told co-anchor Hannah Storm on The Early Show Friday.
Karas added that Melvin's testimony, along with similar testimony expected from the other three women would be "damaging. There's strength in numbers. (Melvin) was very composed. They didn't really touch her on cross-examination. It was a genltle cross-examination. And she did report it to the police."
As Kenney-Baden described the killing, her presentation was sometimes stomach churning in its details of how the bullet entered Clarkson's mouth, how it caused her brain tissue to splatter out on her clothing, how her teeth were shattered by gases from the gun and how her blood splattered and clotted.
"I apologize if I seem callous," she said in apparent deference to Clarkson's mother, sister and other family members seated in the front row. "I don't mean to appear callous to the death of anyone when I do this."
She noted that, when Spector was arrested on Feb. 3, 2003, his blood showed traces of a "neuroleptic" drug that made his hands shake.
"You may have seen his hands shake," she told jurors. "That is one of the side-effects of this drug. It mimics Parkinson's." She said Spector often kept his hands in his pockets to hide this, much as, she said, actor Michael J. Fox does. Fox has Parkinson's disease.
Neuroleptic drugs are tranquilizers used to treat psychotic symptoms, according to medical dictionaries.
Spector listened intently and his hands frequently trembled as Melvin testified, Kauffman observed.
Clarkson's body, with a gunshot wound through the mouth, was found seated in the foyer of Spector's suburban Alhambra mansion early on the morning of Feb. 3, 2003. She had met Spector at the House of Blues on the Sunset Strip, where she was a hostess, and agreed to accompany him on a chauffeur-driven ride to his home.
The trial is scheduled to resume Monday.
Spector faces a possible sentence of life in prison if convicted.