Continuity mistake: When RoboCop and Lewis go to deal with the baseball kids robbing the electrical store, they are shot at and Lewis spins the car round. We cut to a close up of the car and see Lewis get out, meanwhile RoboCop opens his door and puts his hand on top of the car, supposedly to get out. A few moments later he is still siting in the car, arms on his legs. So why did he put his hand up? (00:50:12)
Revealing mistake: Just before RoboCop gets out of the car to walk towards the baseball coach, Lewis shoots at the coach and he jumps back. Watch carefully. Whilst jumping, his hat comes off slightly and you can see the make-up for the hole in his head, which he doesn't receive for a few seconds after this. Seen best in Slow motion on the DVD. (00:50:31)
Continuity mistake: When RoboCop gets out of his car in the scene where the baseball coach is firing at him, the building behind him is reflecting the sun and looks very bright. Less than 2 seconds later we see RoboCop walking towards the electrical shop and the building is very dull looking. Where did the sun go? (00:50:36)
Continuity mistake: When RoboCop is being scraped up against the wall creating a shower of sparks, we cut to views of Cain. In one of these shots of Cain, the background suddenly changes - the wall he's scraping up against is nowhere to be seen and the sparks vanish. In the other shots of Cain, the background is correct. For some reason, a shot was taken from another part in the sequence and added in here, creating an odd continuity gaffe in the background. (01:02:02)
Continuity mistake: RoboCop overtakes Cain on his motorbike, and we see a shot from inside Cain's van. We can see that both of them are very close to the end of the street, and there are two small buildings on the right side of them. The width of those buildings are all the space that stands between them. RoboCop then builds up speed to about 60mph and charges towards Cain, passing several buildings on his right. There is no way RoboCop could have travelled that fast in that short a space, and there is no way he could have passed more than 2 buildings. (01:02:54)
Revealing mistake: Just before the reporter and cameraman are killed on top of the van, a woman is running away from the scene and is shot in the legs, and she falls to the ground. A man comes to pick her up and he gets shot in the back. If you look carefully, you can see the marks that the vest he is wearing make on his back, (which explodes under his clothes making it look like he was shot). (01:39:25)
Continuity mistake: At the start of the movie when the gun store is being robbed, one of them fires a portable rocket launcher at the police car, causing it to roll over and spin. As it comes to a stop just outside the store, it's visible that the driver's side window has been blown out, and the vehicle interior is visible, however when the same guy prepares to fire the bazooka to finish it off, the window has returned and is completely intact.
Factual error: One of the brain surgeons says about Cain's brain, "it's nice and clean in here, there's no damage", except we see throughout the film Cain using the drug Nuke, even a new variation of it called Blue Velvet. When he injects it he's with his chemist Frank, and mentions two of its ingredients, "benzadrine and scopolamine" - no way his brain would be nice and clean.
Visible crew/equipment: When Robocop visits Cain's hideout and sends his car in as a decoy, after he returns to the car, watch the driving shot closely. A wire has magically strung itself across the entrance and attached itself to the back of the car - it wasn't visible from an earlier shot. As the car drives forward it stretches the horizontal wire, and just as a tiny amount of pressure is exerted, the car explodes. Yeah, it's technically a mistake, but I think it's more worth checking out just to see how those tricky effects are achieved.
Continuity mistake: When RoboCop is in the street with his new directives, he shouts "Back" at Lewis and puts his hand down to take his gun out. We can see his hand going down beside his leg and then coming up with a gun, but his hand was nowhere near his leg, and even though we hear the leg opening sound effect, the leg never moves. The same sort of mistake happens after RoboCop 2 destroys the Nuke hideout. RoboCop is investigating, and afterwards puts his gun away. The gun goes down to his leg, but the leg never opens, yet the sound effect is played. Sloppy camera work is responsible for both cases, it should have been higher up.