When Alonzo's crew are about to break down Roger's door, Paul (Dr. Dre) is shown carrying a gun in a holster. The gun is holstered in a right-hand sided holster, yet he is wearing it on his left side. The gun is positioned backwards and in this position, he would not be able to draw the gun with his left hand.
In the final scene when Jake pulls into the driveway, a car is visible through his rear window. As he gets out, the other car's door opens and someone begins to exit, yet when Jake is outside no more of this person is seen. This scene was trimmed to remove a confrontation between Jake and the "Three Wise Men" seen earlier in the movie. However, the scene was not re-shot leaving the "menacing" moment of a mysterious person getting out of a car unexplained.
In the end of the movie Alonzo is stopped in the traffic lights side by side with a gray Mercedes. After he started the car the Hummer and the black van arrived and as he reverses the car, the Mercedes, witch was side by side with him is now behind in the same traffic lane.
When Alonzo is pointing his dual Smith and Wessons at the crack addicts after the attempted rape, in alternating shots the safety levers are sometimes in the 'safe' position and sometimes in the 'fire' position.
After the shootout sequence with the gang members in the LA neighborhood, Jake and Alonzo drive fast to get away. They stop sometime soon after on a highway. When both exit the vehicle, the Monte Carlo is still running, as can be seen from the exhaust pipe which emits smoke. When they are done arguing, Alonzo and Jake get back into the vehicle. Alonzo starts the vehicle although in the previous scene, it was left running.
After Alonzo and Hoyt leave the coffee shop and are in Alonzo's car, he you can see them pass a street with two large buildings in the background. When Alonzo tells Hoyt to roll down his window to listen to the street a couple minutes later, the same street that they passed earlier is in the background.
After stealing Glenn's money and killing him, Alonzo tells his team that they set it up to look as though they stormed the house and Glenn fired on them and they fired back in retaliation. To support this story Alonzo shoots Jeff twice. Once on the left (does not pierce his armor) and once on the right (which pierces his armor). A few minutes later we see Jeff being taken to the ambulance on a stretcher holding blood stained mesh and dressing on his left side, but in fact it was the bullet on the right that had pierced his armor and injured him.
When Alonzo and Jake stop the college kids in a lime-green VolksWagen, at first the outside environment and vehicles are all dry. As Alonzo chases the VW and slides in front of it, the ground is wet. After that, the windshield on Alonzo's car is observed to have water droplets on it as if it had been raining. Again, immediately following that, the windshield appears dry. In the next few shots, the viewable windows on the VW alternate between being wet and dry.
On the roof top, Alozno throws Jake through a window. In the reverse shot, the glass has disappeared from the upper unbroken section of the window. When Alonzo goes back to the window a few moments later he knocks off bits of glass that reappeared.
When Smiley has Jake in the bathtub, the wide shots show Smiley holding the shotgun with both hands. The cuts from Smiley's point-of-view show him holding the shotgun with only hand. Showing both hands would have blocked Jake out of the shot.
After Hoyt stops the two crackheads from raping the girl and
Alonzo comes on the scene to question the girl, he asks her "Why are you out here? They probably got AIDS, you know? Why are you not in school?". At this point her sweater is on both shoulders. Immediately after asking the question, the scene cuts and her sweater is off her left shoulder.
After stealing Sandman's money, three bullets are fired through the back window of the Monte Carlo as Jake and Alonzo drive off. The first bullet would have already destroyed the whole window. It would have broken into thousand little pieces.
After Alonzo steals the money from Sandman's wife and during the subsequent shootout between Alonzo and the residents gang members, you see the gang members run after Alonzo's car while firing their handguns. You'll notice the gangsters, who are wearing their baggy pants in they typical gangster fashion (loose and low, around their buttocks, with their underwear exposed), are running and their pants are not falling down. In reality, all the boys were wearing belts. Even without a belt, one learns to adapt to running to or from the wrong situations.
Alonzo would have not been allowed to board an airplane given the physical condition he's in especially a bullet wound in his rear end, and most likely not last the flight time, hence dying on board, no matter what the destination is, since blood would be constantly leaking out of the wound.
After stealing Sandman's money, three bullets are fired through the back window of the Monte Carlo as Jake and Alonzo drive off. At the angle they were fired at, all three bullets would have exited the car through the windshield or would be driven through the driver and/or passenger seats, yet all three bullets magically disappear without striking anything once they go through the back window.
Two different designs of police badges are used in the movie. On close up shots where the badges are clearly visible, a generic imitation of the LAPD badge is used (most notable with the image of Los Angeles City Hall omitted). On all other shots, where the badge is seen from farther away, a badge design more closer to the real LAPD badge is used.
The goof item below may give away important plot points.
At the end of the movie when they are outside Alonzo's house, Jake jumps on the car and Alonzo proceeds to smash his car into numerous cars on the street, however at the end of the movie when Alonzo's driving, right before he gets shot up, the car hardly has a ding other than the front windshield cracked. What happened to the damage?