Olsen 'silent' on Ledger overdose

US government investigators want to question actress Mary Kate Olsen about how Heath Ledger got two painkillers that contributed to his overdose death, a law enforcement official says.

The official said Olsen’s lawyer had twice refused requests to have her sit down with investigators probing the death of Ledger, who co-starred in the new Batman film, 'The Dark Knight'.

The official, who spoke anonymously, says Olsen wants immunity before she speaks to drug agents. There was no immediate response to a message left with Olsen’s representatives.

The New York Post first reported details about Olsen pressing for immunity.

The official confirmed a report that Olsen – a close friend of Ledger who learned about the 28-year-old Australian actor’s death in a frantic phone call from a masseuse – wants a promise of immunity before she speaks to the Drug Enforcement Administration.

The activity demonstrates that federal authorities are still trying to find out how Ledger got some of the drugs that killed him.

DEA investigators suspect the painkillers oxycodone and hydrocodone found in his system were obtained with fake prescriptions or other illegal sources, the official said. Oxycodone is sold as OxyContin and hydrocodone as Vicodin.

The other drugs that resulted in what the medical examiner called “acute intoxication”, including anti-anxiety and sleeping pills, were prescribed legally by doctors in California and Texas, the official said.

Authorities have obtained a subpoena that could force Olsen to appear before a grand jury if negotiations with her lawyer fail, the official said. Other potential witnesses all have answered questions voluntarily, including doctors, Ledger’s ex-girlfriend Michelle Williams and anyone who was in his apartment around the time of his death, the official added.

The DEA’s New York office declined to comment on the stalemate, first reported yesterday by the New York Post. There was no immediate response to a message left with a spokeswoman for Olsen.

The masseuse discovered Ledger’s body on January 22 after the actor had completed filming his role as the Joker in the new Batman film.

Police say the masseuse spent nine minutes making three calls to Olsen before dialling emergency hotline 911 for help, then called the actress a fourth time after paramedics arrived. At some point during the flurry of calls, Olsen, who was in California, summoned her personal security guards to the apartment to help, police said.

Shortly after Ledger’s death, Olsen issued a statement that read: “Heath was a friend. His death is a tragic loss.”