According to sources, all of the drugs in Ledger's body and discovered nearby in prescription bottles were legally obtained from two physicians - with the exception of OxyContin, a powerful painkiller.

Investigators "are trying to ID the source of the OxyContin," a source said. "Did it come from a dealer, from a friend? If he had a bottle from a friend, was it taken by someone else before police responded? That is what is trying to be determined."

But Olsen, the tabloid claims, is refusing to talk until she gets immunity from prosecution. Immunity, one naturally wonders, from what? Would supplying a prescription drug to Ledger carry so much jailtime, if Olsen even did that? Or is she worried about something more nefarious — like tampering with a crime scene?

Or perhaps Olsen's alleged request is more routine, a pro forma form of legal hardball designed to bring authorities into contact on the most favorable terms possible. But unlike most parties to an investigation, Olsen is a celebrity with an image to uphold, an image that can be damaged simply by trying to get immunity in the first place — as today's Post story shows.