Fact or fiction? Zero Dark Thirty film-makers want it both ways

It is hard to escape the impression that the film-makers behind Osama hunt thriller Zero Dark Thirty are trying to have their cake and eat it too.

On the one hand, they brandish the film's factual credentials and intimate CIA access; on the other, they stand behind an artistic defence of the murky causality presented in relation to torture.

Zero Dark Thirty begins with a line saying it is "based on first-hand accounts of actual events".

This is turning out to be the most troublesome aspect of the movie for director Kathryn Bigelow and screenwriter Mark Boal, who have tied themselves in knots trying to justify their depiction of the use of torture - or, euphemistically, "enhanced interrogation techniques"- in the investigation leading to the killing of the terrorist leader in May 2011.