Continuity: Martin's collar when checking himself in the mirror.
Continuity: Martin's cut over his right eyebrow appears and disappears.
Factual errors: Joey Pinero hands Marty a CD of Dulce Pontes, and says that the music he liked is the fourth track. In that album, the song used in the film is, in fact, the first track.
Continuity: The video recording of both psychiatrist's interviews with Aaron do not match the meetings we originally saw.
Continuity: Martin's bottle of water changes position on the table beside him between shots as he watches TV.
Errors made by characters (possibly deliberate errors by the filmmakers): In one of the first scenes in Martin Vail's office, he uses the word "illegibly" instead of the correct word "allegedly."
Continuity: While Vail, Tommy, and Naomi are discussing the porno tape, the blue screen of a computer monitor is reflected in Tommy's glasses. But in the reverse shot (showing Vail) the monitor is off.
Factual errors: The blood at the scene of the murder (where Mr.Vail comes in some days after the murder), and the blood on Aaron's sneakers, shown in the court, should be brown, because some time has passed and blood coagulates. When blood coagulates it turns from red to brown.
Continuity: When Vail and Shaughnessy are having dinner in the Asian restaurant, the rib on Shaughnessy's plate disappears between shots.
Revealing mistakes: The cover of the USA Today Andre Braugher's character is reading when he's first introduced consists mostly of a big three-line headline and a the lengthy text of a story. No newspaper in 1996 would run a cover without a large photo or graphic high on the page, especially not USA Today.