What was that again?

Perhaps this explains why Bill Clinton thinks he was the nemesis of Osama, and John Kerry says he was running guns to the Khmer Rouge:

MAASTRICHT - People who consciously pretend as if they can not remember something, thus to lie, with that behaviour disturb their real memories. As a result, they can eventually remember little of what in reality has happened. That becomes clear from research from the University of Maastricht.

....According to researcher Kim van Oorsouw, who will graduate November 30th following her doctoral study into amnesia and criminal behaviour, suspects who say they have a black-out, should be directly subjected to a memory loss test.