My uncle was involved with this film. The cameraman, Mike Gray, had to go into hiding in CA for months with the film canisters because he fillmed the evidence of the real bedroom door with bullets going one way. He went behind the yellow police tape the day before Hanrahan's men switched to the false door that showed 2 way shooting.
In 2021, the film was selected for preservation in the United States National Film Registry by the Library of Congress for being "culturally, historically, or aesthetically significant".