The end of August marks another significant, if less widely noted, anniversary than that of the Democratic convention riots. On August 30, black activist Fred Hampton would have turned 40 years old—if he had not been shot to death in his bed, probably while sleeping, by policemen attached to the office of state’s attorney Edward V. Hanrahan.

The making of The Murder of Fred Hampton began as a follow-up to the 1969 film American Revolution 2, which is also being shown at Filmmakers next Wednesday. American Revolution 2 evolved from media coverage of the 1968 convention riots; it was created by the Film Group, a Chicago production company whose stock-in-trade was innovative TV commercials.

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The quick response of the attorneys and Gray’s film team proved essential in ultimately discrediting the official account of the raid. When state’s attorney Hanrahan’s explanation of the shootings met with angry and informed rebuttals from the Panthers, Hanrahan released an “exclusive” detailed description of his account to the Chicago Tribune—because, Hanrahan haughtily informed other reporters, “that newspaper in my opinion gave a very balanced, fair report of the events that occurred.” The tactic backfired; other news media, angered by the slight, dug deep to expose the blatant discrepancies between Hanrahan’s story and the visible evidence. Hanrahan’s officers also produced a video “reenactment” of the raid, a now clearly laughable attempt at self-justification that fell flat.

Fred Hampton opened doors, too—and they haven’t closed yet. Aside from its dramatic intensity, the film has a potent effect today because it illuminates the history behind many current events. Despite the media’s tendency to portray the Panthers as black supremacists, Hampton was deeply interested in promoting multiracial coalitions. The struggle to end black oppression, Hampton felt, had to be fought by black socialists, not black capitalists. In this ideology lie the roots of the current standoff between the Eugene Sawyer faction in City Hall and the progressive faction led in part by Bobby Rush. Rush, now alderman of the Second Ward, figures prominently in The Murder of Fred Hampton: in 1968-’69, he was the Illinois Panthers’ minister of defense. In one of the movie’s most chilling moments, a Panther attorney notes that a police officer leaving the site of Fred Hampton’s apartment the night of the raid was heard to say, “Bobby Rush is next.” But the alderman-to-be wasn’t home when the police came calling.