Prosecutors in the murder case of music producer Phil Spector have demanded that a dead woman's fingernail be put forward as evidence.
Phil Spector (centre) pleaded innocent to murder in November
The nail, which was overlooked by police investigating Lana Clarkson's shooting, is blackened with gunpowder according to court papers.
The evidence could indicate that the 40-year-old actress killed herself at Spector's Los Angeles mansion.
Spector, who worked with The Beatles, has denied murdering Clarkson.
Defence lawyers have so far refused to turn over the fingernail, which was identified last month as a mystery "item of physical evidence".
This comes despite a plea from Deputy District Attorney that the fingernail should be submitted as evidence to the court.
Robert Shapiro, who had represented Spector, has been asked to identify the item, say where it was found, disclose who has had access to it and what tests have been performed on it.
The gunpowder-stained fingernail could be used in determining how Clarkson was shot.
The revelations that it is a torn piece of the victim's fingernail will compell lawyers to discuss the issue in the next court hearing on 17 February.
Spector's new lawyer Leslie Abramson has refused to discuss the fingernail, but says she will file a response with the court ahead of the hearing.
The change of representation should make no difference to the disclosure of the fingernail, according to the authorities.
"It's part of the evidence and we're entitled to have it," said district attorney spokeswoman Sandi Gibbons.
The crime scene was originally searched by the authorities and then Spector's defence team.
The 62-year-old was arrested last February after Clarkson was found shot dead in the hallway of his hilltop mansion.
He remains free on bail of $1 million (£546,000), and in an interview with Esquire magazine, protested his innocence and suggested Clarkson killed herself.