Did Bush authorise torture?

In December last year, the ACLU released what seemd to be a smoking gun for the US policy of torture: an email suggesting that President Bush himself directly authorised the use of torture. The White House issued the usual non-denial denial, but now the issue has resurfaced. In an article on the history of waterboarding (and particularly its past use and unequivocal treatment as torture by US legal and military authorities), ABC news notes that

current and former CIA officers tell ABC News there is a presidential finding, signed in 2002, by President Bush, Condoleezza Rice, and then Attorney General John Ashcroft approving the techniques, including water boarding.

(Emphasis added).

If true, this would constitute cast-iron evidence that the President of the United States had conspired to violate both US and international law - something far more serious than getting a blow-job in the Oval Office. I guess we'll just have to hope that somebody leaks it...