The controversy surrounding Karthryn Bigelow’s Zero Dark Thirty continues to bubble. Bigelow and Mark Boal, the film’s writer, have drawn flack from both the left and the right for including scenes of CIA torture in their dramatisation of the hunt for Osama Bin Laden.

Republican senator John McCain has criticised the film-makers for suggesting that the security forces would behave in such an ungentlemanly fashion. Meanwhile, various liberals have detected implicit endorsement of state-sponsored torture in the Oscar-nominated picture. Information derived from water-boarding eventually leads the protagonist to Bin Laden’s lair.

After winning the top prize from the New York Critics Circle, Bigelow, who took home an Oscar for The Hurt Locker, addressed the issue.

“I thankfully want to say that I’m standing in a room of people who understand that depiction is not endorsement,” she said. “And if it was, no artist could ever portray inhumane practices; no author could ever write about them; and no film-maker could ever delve into the knotty subjects of our time.”

The Senate Intelligence Committee, headed by Democrat Diane Feinstein, has also been investigating whether Boal and Bigelow were granted inappropriate access to classified CIA material.

Will the scandal hurt Zero Dark Thirty at the Oscars? It remains second favourite to Lincoln in the race for best picture. But the gap is widening.