Film-maker Joe Berlinger and his production company Third Eye Motion Picture Company have filed legal papers opposing Chevron’s request for raw footage from the filming of Berlinger’s documentary Crude.

The film reports on an environmental catastrophe in the Amazon rainforest and the decades of fierce litigation that ensued between the indigenous populations affected by the damage and the US corporation allegedly responsible for the harm. Crude debuted at Sundance in January 2009.

According to a press release issued by Berlinger, Chevron and its lawyers hope to use material in their defense of an environmental lawsuit in Ecuadorean courts. On April 9 Chevron asked a New York federal judge to order Third Eye to release more than 600 hours of footage.

“Unused film footage and other editorial materials from Crude are protected by the journalist’s privilege under federal law and the First Amendment,” Maura Wogan of Frankfurt Kurnit, the lawyers for Berlinger and his production company, said. “We will vigorously oppose Chevron’s attempt to get to these materials.”

“Documentary film-makers play an essential role in exposing social injustice,” Berlinger said. “As with traditional journalists, their sources must be protected or we risk the demise of this kind of comprehensive investigative reporting.”