In the jail-cell scene right before O.J. is to go to court, he is shaving his face while talking to the guard about the possible outcome of the verdict. When he is next seen in the courtroom, he clearly hasn't shaved for a few days.
The iconic phrase "If it does not fit, you must acquit" was actually formulated by attorney Gerald Uelmen.
In real life, Johnnie Cochrane delivered the line "If it does not fit, you must acquit" while wearing a knit cap similar to one OJ was alleged to have worn the night of the murders.
During the end montage of updates on the real-life people involved with the trial, Massachusetts is misspelled as "Massachussetts" in the update on F. Lee Bailey.
While talking about her motivations as a prosecutor, Marcia Clark says that she was raped while vacationing in Italy; in reality, she was raped in Israel.