In a letter sent today to White House counsel Fred Fielding, Senate Judiciary Committee chairman Patrick Leahy and House Judiciary Committee chairman John Conyers say their committees will consider next month whether "the White House is in contempt of Congress."

The issue -- or at least the immediate one -- is the Bush administration's refusal to turn over internal White House documents or make Harriet Miers or Sara Taylor available for testimony in Congress' probes of the firing of U.S. attorneys last year. In their letter, Leahy and Conyers complain that the White House has refused to comply with congressional subpoenas based on a "blanket" invocation of "executive privilege" that isn't even signed by the president himself.

"A serious assertion of privilege would include an effort to demonstrate to the committees which documents, and which parts of those documents, are covered by any privilege that may apply," the chairmen say. They want Fielding to provide them with a privilege log that lists each document that's being withheld and provides a description of the nature of the document, the source, the subject matter, the date of the document, the identity of anyone who received a copy of the document, and the specific legal basis for claiming that the document is protected by executive privilege.

Such logs are commonly required in civil litigation, and Leahy and Conyers note that the Bush administration -- like other administrations -- has provided them to Congress when information has been withheld in other investigations.

Leahy and Conyers tell Fielding that, with or without the log they seek, their committees will "move to proceedings to rule on your claims and consider whether the White House is in contempt of Congress" on the morning of July 9.

"We were disappointed that we had to turn to these subpoenas in order to obtain information needed by the committees to learn the truth about these firings and the erosion of independence at the Justice Department," they write. "We are even more disappointed now with yet further stonewalling. Whether or not we have the benefit of the information we have directed you to provide by July 9, we will take the necessary steps to rule on your privilege claims and appropriately enforce our subpoenas backed by the full force of law."