Continuity: The scene on the highway where Mel Gibson and Danny Glover are chasing the black Mercedes in their Pontiac, the windows on the Mercedes repeatedly change between tinted and non-tinted.

Continuity: In the trailer chase scene, when Riggs is being dragged by the plastic wrap, it cuts away to a far shot of Riggs on the table.  The "plastic" he is holding on to is very obviously a thick metal cable wrapped in saran wrap or something to make it look like plastic.

Continuity: During the mobile home chase, you can see a white car following Murtaugh. In the next shot, when he starts to overtake the mobile home, the car is black.

Continuity: In the scene where Mel Gibson is at his wife's grave, Joe Pesci comes along to give him advice. In the scene he was in previously he had cuts across his face. At the cemetary the cuts are gone, then they reappear inthe following scene at the hospital.

Factual error: When the sedan is struck by the train, it launches into the air and explodes, but doesn't sustain severe impact damage. The car rolls over in midair and it is nearly straight - not heavily bent or crushed as the entire left side should have been. Even a slow moving train heavily batters the passenger vehicle it hits.

Continuity: When Riggs and Murtaugh are talking about how much ammo they have, Murtaugh says he has 6. He then shoots 2 and say he has 4 left. Next time Riggs asks Murtaugh says he has 2 left. When Butters is shot, Murtaugh fires 2. So he should have 0 shots left. However he still has one more, because he shoots Jet Li's brother. So where did the 7th bullet come from?

Plot hole: When Mel Gibson, Danny Glover, Rene Russo, and the others are tied up and lying on the floor of the burning house, they can't stop coughing. However, the bad guys (who are also in the burning house) are just standing around laughing, wouldn't you think that they would be inhaling smoke also?

Factual error: Early in the film, while Riggs, Roger and Leo are on the Code 7, Riggs has to place his Beretta in his mouth so he can board the larger ship. The beretta 92FS is a heavy handgun, it would be very dificult, if not impossible, for it to be held in the mouth, let alone to wave your head about like in the film. I own a Beretta 92 and I've tried it, so Im speaking from experience.