Victims' rights groups fear movie will challenge music mogul's guilt.
Four years ago music producer Phil Spector was convicted of murdering B-grade movie actress Lana Clarkson at his Los Angeles castle home.
Many believe Clarkson's death was a tragedy waiting to happen - Spector was well known for terrorising women, and musicians, with guns - but the guilty verdict was a surprise in a town where celebrities with far stronger evidence against them typically walk free.
Now a new HBO-produced film to be screened next week, Phil Spector, has sparked a row between victims' rights groups and those, like the film-makers, who believe the evidence against the producer did not rise to the threshold of "beyond reasonable doubt".
Al Pacino, who stars as Spector, has revealed that, while he was undecided about Spector's guilt, David Mamet, the movie's writer and director, was certain of his innocence.
Helen Mirren stars as Linda Kenney Baden, Spector's lawyer in the first of his two trials for Clarkson's murder in 2003. He was accused of putting a gun in her mouth and shooting her.
Spector's wife, 32-year-old Rachelle Spector, said she believes that the film, despite leaning towards the conclusion that Spector was wrongly convicted, is a breach of client-attorney confidentiality between Spector, 73, and Kenney Baden, who was an adviser to HBO.
She fears it will serve to further cement her husband's reputation as a "freak and a megalomaniac".
"My husband is not this fictionalised monster," said the singer-songwriter. "They didn't get OJ Simpson or Robert Blake or Michael Jackson, so they had to get somebody and they spent $30 million to get my husband. They hadn't convicted a celebrity in 40 years, so the pressure was on."
Rachelle's efforts to clear her husband's name are an uphill struggle. His case is on final appeal on procedural grounds, but there is no clear path to a judicial review.
Despite her doubts about the film, Mamet may prove to be Rachelle Spector's best ally. Vikram Jayanti, maker of the BBC Arena documentary The Agony and Ecstasy of Phil Spector, who was also a consultant on the HBO film, and Kenney Baden both say the judge in Spector's trial had refused to admit evidence that would have shown he could not have killed her.
The producer's supporters claim the lack of blood spatter on the white jacket he was wearing proves he could not have been near her. They say judge Larry Fidler was so determined to avoid the trial turning into an OJ Simpson-style circus, he excluded the evidence.
Spector's eccentricity lies at the heart of Mamet's drama. "Do we convict people because of how they look, what they look like, whether they're freaky-looking? Or do we convict people on the evidence?" Kenney Baden asked on CNN last week.
But supporters of the murdered actress say they are ready to take their protest to voters during award season if, as they suspect it will, the film makes a case for Spector's innocence.
"Mamet, the writer, has publicly stated that he feels Phil Spector is innocent and should not be in prison," says spokesman Ed Lozzi. "We fear that he will rewrite history and portray Lana Clarkson as responsible for her own death. That is not acceptable, and if he does so, there will be consequences from us."
Jayanti said that despite Spector's evident oddness, he believes "audiences for my film came in hating Phil Spector and thinking he was a murderer but left with a reasonable doubt". Mamet's film will do that on a larger scale, he predicts. "People will ask, was it a fair trial? Let's take another look at what happened that night."
What: Phil Spector, starring Al Pacino and Helen Mirren
When: Tuesday, March 26, 8.30pm
Where: Sky's SoHo channel.