The chairman of the House Judiciary Committee on Monday threatened to serve subpoenas on former Attorney General John Ashcroft and two others associated with the Bush administration's interrogation policies if they don't agree to testify.

If the three including John C. Yoo, the former assistant deputy attorney general, and David Addington, Vice President Dick Cheney's chief of staff do not reply by Friday, "I will have no choice but to consider the use of compulsory process," Rep. John Conyers, D-Mich., wrote in letters to them.

That's Washington-speak for issuing congressional subpoenas, tough talk that Conyers has leveled at the White House before. A previous dispute is being hashed out in federal court, with Conyers' committee suing White House Chief of Staff Josh Bolten and former presidential counsel Harriet Miers for refusing to comply with subpoenas on the firings of federal prosecutors. The White House maintains that their testimony is off-limits from congressional oversight under executive privilege.