As a self-proclaimed “rock chick” photographer, Stephanie Jennings was overwhelmed when she met the veteran record producer Phil Spector while snapping celebrities at a New York party.

Spector was full of intimate stories about working with the Beatles and Leonard Cohen. He was charming and funny. But when he started drinking, she claims, he pulled a gun on her and held her against her will for 48 hours.

It was part of an alleged pattern of behaviour that culminated in Spector’s appearance in a Los Angeles courtroom last week on a charge of murder.

This week Jennings, who is in her mid-thirties, is expected to tell the jury how Spector could “flip” from being a colourful raconteur - recalling how he created the “wall of sound” as heard on Ike and Tina Turner’s hit River Deep, Mountain High, or the Beatles album Let It Be - into a possessive gun-wielding bully.

This, the prosecutors claim, is how Spector ended up killing Lana Clarkson, a blonde 40-year-old B-movie actress, as she tried to escape from his Los Angeles chateau four years ago. Spector, now 66, says she shot herself while playing a game called “kissing the gun”.

Jennings, a petite brunette, is no stranger to the music scene, a fellow photographer from her native Philadelphia confirmed. “She cut her teeth on local bands, proving herself one of the boys. When she moved onto dealing with big names like Iggy Pop, she never took any nonsense,” he said. “She knew how to handle their egos.”

But taking on Spector, who has spoken of a battle with schizophrenia and has never denied stories that he threatened musicians such as John Lennon and Dee Dee Ramone with a gun, proved too much for Jennings.

She told investigators that after meeting Spector at a Rock and Roll Hall of Fame party in 1994, she agreed to visit him in Los Angeles. When she wanted to leave, he allegedly bolted the front door and trapped her at gunpoint. Only after some visitors arrived did she escape.

Following her back to New York, Spector allegedly turned up at her room in the Carlyle hotel, talked his way in and then, when she tried to leave, blocked the door with a chair and threatened her with the gun again until she calmed him down with protestations of love.

Jennings is one of four women with similar tales, whose evidence for the prosecution may send one of music’s most colourful characters to jail for the rest of his life if he is convicted. The first of them, Dorothy Melvin, a former manager of the comedian Joan Rivers, has already testified he brandished a revolver at her and struck her on the head.

The producer, who friends claim has not had a drink since he married his wife Rachelle, 26, last September, knows the danger he is facing. Last week he interrupted his £2,000-an-hour lawyer to deny to reporters gathered on the courtroom steps that he had ever pulled a gun on these women, calling it “all lies”.

In the run-up to the first televised trial in Los Angeles since O J Simpson’s in 1995, the women have been assiduously courted by the media, say lawyers close to the case, although no book or film deals can be signed until a verdict is reached.

All are ex-girlfriends who have told police how Spector terrorised them, pressing a hand-gun into a cheek or brandishing a pump-action shotgun. “Their memoirs will be worth more if he is found guilty,” said one lawyer.

Whatever the verdict, the biggest media cheques are likely to go to the chauffeur, Adriano De Souza, who would drive Spector, wearing one of his 400 wigs with matching lipstick, into Hollywood for a “night crawl” up to four times a week .

De Souza has reportedly said that Spector was “a hit with the ladies”.

Although elderly and diminutive, he was attractive to the hungry young women who work and play in Hollywood’s sleazy bars and nightclubs: he had a top-of-the-range Mercedes, stellar connections and access to any club he chose.

Clarkson worked in one of these, the House of Blues on Sunset Strip. When her shift ended at 2am she agreed to return to Spector’s 25-room home, where they drank and talked.

The police believe she eventually tried to leave and Spector tried to stop her with his gun. Whatever happened next, she died shortly before 5am on February 3, 2003.

The jury is expected to reach its verdict in July.

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