But the Central Intelligence Agency redacted the number of tapes destroyed when it provided an accounting for a federal lawsuit that seeks release of its interrogation records. On Monday, the Justice Department said there were 92  a stunning amount of evidence-shredding that needs further scrutiny.

The released memos were written by the Justice Department’s Office of Legal Counsel, which is supposed to ensure policies comply with the Constitution and the law. They make it chillingly clear how quickly that office was rededicated to finding ways for Mr. Bush to evade, twist or ignore both. Some low points:

 In an Oct. 23, 2001, memo, John C. Yoo, then a Justice Department lawyer, explained how Mr. Bush could ignore the Fourth Amendment and the Posse Comitatus Act and deploy the military within the United States in “anti-terrorist operations.” In the same memo, Mr. Yoo argued that Mr. Bush could also suspend First Amendment rights to free speech and a free press.

 On March 13, 2002, Jay Bybee, the head of the office at the time, wrote that Mr. Bush could ignore the Geneva Conventions and the anti-torture treaty. Mr. Bybee, who now has a lifetime seat as a judge on a federal court, said Mr. Bush was free to send prisoners to countries known to employ torture  a practice known as extraordinary rendition  as long as there was no agreement to do the torturing.

 On Jan. 15, 2009, five days before Mr. Bush left office, Steven G. Bradbury, the head of the counsel’s office in Mr. Bush’s second term, repudiated the earlier memos and tried to excuse them by saying they were made “in a time of great danger and under extraordinary time pressure.” They were, but that should have led honest lawyers to exercise extra prudence, not to rush into sweeping away this country’s most cherished rights.

The Justice Department’s internal ethics office is reviewing these and other memos and trying to decide whether political appointees knowingly twisted their interpretations of the law to provide legal cover for decisions made by the White House. At least two Congressional committees are, quite rightly, also looking into these issues.