The U.S. Senate Intelligence Committee has begun an examination of contacts between the CIA and the filmmakers behind Zero Dark Thirty, a movie about the hunt for Osama bin Laden.

The film has come under intense criticism in Washington for its depiction of torture as a tool used to extract intelligence about the al-Qaeda leader.

A committee headed by Senator Dianne Feinstein is to examine whether the CIA granted "inappropriate access" to director Kathryn Bigelow and screenwriter Mark Boal.

Zero Dark Thirty charts the nine-year hunt for al-Qaeda leader Osama bin Laden and climaxes in the successful raid on bin Laden's compound in May 2011, when he was killed by U.S. forces.

The Senate committee is especially interested in scenes in the movie depicting torture as an effective tool and wants to know if those details came from CIA sources.

Senators Feinstein, John McCain and Carl Levin have criticized those scenes as inaccurate, saying torture was not effective in gaining information about bin Laden’s whereabouts. The senators oppose any use of torture.

They have sent a letter to Sony Pictures, the film's distributor, asking that a disclaimer be added to the movie.

Several meetings with CIA

Reuters is reporting the investigation will examine records charting contacts between intelligence officials and Boal and Bigelow.

The conservative group Judicial Watch has released government e-mails and memoranda that show several meetings between the filmmakers and CIA officials, including Michael Morell, the CIA's deputy director at the time and now the agency's acting chief.

Morell made public a message to CIA employees last month saying that Zero Dark Thirty is a dramatization and should not be interpreted as realistic.

"CIA interacted with the filmmakers through our Office of Public Affairs, but as is true with any entertainment project with which we interact, we do not control the final product," he said.

Zero Dark Thirty, he wrote, "takes significant artistic licence, while portraying itself as being historically accurate."

Peter Bergen, a journalist and author of the book Manhunt: The Ten-Year Search for Bin Laden from 9/11 to Abbottabad, says he saw nothing in his own research to prove that  torture was an effective tool in the hunt.

The real danger is that people seeing Zero Dark Thirty may take a film that is partly fiction as the whole truth, he told CBC News.

"Some of the reporting is accurate, but some of it is not accurate," Bergen said. "And I think tens of millions of people around the world, including in Canada, are going to come this film, and it's going to colour the way they view what happened and the hunt for bin Laden.

"And we now have the intelligence committee in the United States saying that their portrayal of what happened is grossly misleading  and inaccurate, which I think sort of speaks for itself."

'No single method'

Boal and Bigelow, an Oscar winner for The Hurt Locker, released a statement last month defending the depiction of torture in their film.

"The film shows that no single method was necessarily responsible for solving the manhunt, nor can any single scene taken in isolation fairly capture the totality of efforts the film dramatizes," the statement said.

"One thing is clear: the single greatest factor in finding the world's most dangerous man was the hard work and dedication of the intelligence professionals who spent years working on this global effort."

Zero Dark Thirty has had limited release in New York and Los Angeles and is already being mentioned as an Oscar contender.

A special screening has been set up in Washington for Jan. 8. It will open widely on Jan. 11.