Wow, so good of them to notice....

Rep. Bill Delahunt (D-MA) wanted some clarity during his questioning. Was the attorney general really saying that anyone who acted pursuant to a Justice Department legal opinion was "insulated from criminal liability?"

Mukasey wanted to say it more carefully. "I think what I said was that we could not investigate or prosecute somebody for acting in reliance on a Justice Department opinion."
[ cf Mukasey: The Law Is What The Justice Department Says It Is ]

Just how bad were John Yoo's now-infamous torture memos?

After numerous calls from Congress for the DoJ to get digging, the Justice Department's Office of Professional Responsibility told Congress in February that it is busy investigating Yoo's infamous August, 2002 torture memo. That one, signed by then Office of Legal Counsel chief Jay Bybee, limited the definition of torture to physical pain "equivalent in intensity to the pain accompanying serious physical injury, such as organ failure, impairment of bodily function, or even death." It was the administration's so-called "golden shield" which permitted the CIA to use its most aggressive interrogation techniques, such as waterboarding.

And then in March of 2003 came Yoo's memo broadly authorizing the use of torture by military interrogators on unlawful combatants. Now OPR has told Sen. Sheldon Whitehouse (D-RI) that it will be investigating that memo, too.
[ cf Internal Justice Dept. Investigation Includes Yoo Torture Memo ]