The Bush DOJ may not usually be inclined to hold its own members accountable for criminal wrongdoing. But when the alleged wrong-doing consists of embarrassing the administration by revealing the existence of a program that was illegally spying on the American people, the wheels of justice seem to start turning.

Last month, as we noted at the time, Newsweek unmasked the man, Thomas Tamm, who leaked to the New York Times the news that the NSA had been conducting a secret wiretapping program that was being concealed from the FISA court.

And as the magazine reported, Tamm, who spoke on the record to Newsweek for its story, has been in federal law enforcement's sights thanks to his fateful decision.

Now, DOJ has written a letter to his lawyer -- obtained by Salon's Glenn Greenwald -- asking whether, in light of his decision to speak to Newsweek, Tamm "is willing to reconsider his prior refusal to speak with agents of the FBI and/or to testify before the Grand Jury regarding his knowledge of and/or participation in the disclosure of TSP-related information to [James] Risen, Mr. Lichtblau and others."

(Risen and Lichtblau, of course, are the New York Times reporters who first reported on the program, based on Tamm's leak.)

The letter, signed by Steven Tyrrell, the chief of DOJ's fraud section, continues with what appears to be a veiled threat to subpoeana Tamm:

if I do not hear from you by [January 7], I will assume that Mr. Tamm is not interested in submitting to a voluntary interview or testifying before the Grand Jury.

In its report last month, Newsweek wrote that federal agents have "pursued [Tamm] relentlessly for the past two and a half years ... raided his house, hauled away personal possessions and grilled his wife, a teenage daughter and a grown son. More recently, they've been questioning Tamm's friends and associates about nearly every aspect of his life."

That pursuit appears to be continuing -- even as the department declines to bring charges against anyone in connection with the illegal program itself that Tamm revealed.