The movie's ending sequence includes an information card implying that William O'Neal committed suicide after his PBS interview aired, on 15 January 1990. That isn't accurate. The PBS series 'Eyes on the Prize' did debut on that date, but the O'Neal interview did not air until 9 February, three and a half weeks after O'Neal's suicide. No one knows why O'Neal chose kill himself on 15 January, and his family disputed that his traffic fatality was a suicide. They claimed it was an accident.
When Fred Hampton visits Jake Winters' mother, there are Longaberger pottery coffee cups on the table. Longaberger didn't launch the pottery line until the 1990's.
During the police raid on Black Panther headquarters the Chicago P.D. is depicted employing 1966 Ford full-size four-door hardtops. Police units at the time were universally sedans, which when Fords were from the "Custom" line. The Custom line did not include four-door hardtops.