Prosecutor: Put a Lid on Letterman Evidence

Offical hoping to keep documents about alleged blackmail scheme under wraps

What exactly did his alleged blackmailer have on David Letterman?

We might not know for a long time, if a Connecticut prosecutor has her way. Suzanne Vieux filed a motion in Norwalk Superior Court seeking to keep sealed search warrants that investigators used to arrest a CBS News producer for trying to extort $2 million by revealing the Late Show host's affairs. She also wants Thursday's scheduled hearing to take place behind closed doors.

Disclosing the info to the public could end up putting several witnesses at the center of a media circus, Vieux argues, and potentially harm the government's case against suspect Robert "Joe" Halderman.

The 48 Hours Mystery man was arrested two weeks ago after police executed the warrants on his house in Norwalk and a 2006 Honda Accord. He has since pleaded not guilty.

Halderman's attorney says he hasn't seen the documents but hints they could be more "sensitive" to Letterman than Halderman and that the information "has to be disclosed."

Letterman, 62, 'fessed up to his affairs before Halderman's arrest was announced.