The President "doesn't remember," or "doesn't believe that he ever said that."
The Vice-president "can't recall," or "never said that."
The Vice-president's chief of staff "can't recall," doesn't remember" and "has no recollection."
The Attorney General "can't recall," "doesn't remember," "wasn't precise in his choice of words," "has no recollection," and "doesn't dispute that the decision was made but doesn't recall making the decision."
Maybe it's time for the EPA to run tests on air, soil and water samples taken from the general vicinity of the White House. I wonder if they have a test for plain old bull-shit . . .