Continuity mistake: When Dredd is talking to Hershey in her wrecked apartment the cut above his eye runs across his eyelid but later on when he's talking with Rico in the Janus lab the cut follows his eyebrow and doesn't touch his eyelid.
Continuity mistake: In the scene where one of the "high council" is speaking (behind a desk or pedastal), there is a close-up shot of the highest ranking council member's face. In his nostril you can see a dry booger. They then change the shot and then come back to a close-up of his face. The booger is no longer there. Sorry if this is a bit gross, but I found it amusing.
Continuity mistake: As Dredd and Fergie are escaping from the Halls of Justice they jump on one of the bikes. As they jump on the bike Dredd is wearing a jacket but in the next frame as he activates the bike his jacket has suddenly disappeared.
Continuity mistake: When Rico is activating the ABC-robot, he tells it "we're going to war". His face is then very close to the robot, only inches away. The angle changes to a shot over Rico's shoulder, and his head is now much further away from the robot, even before the robot starts to sit up.
Continuity mistake: At the end when Rico is falling off the Statue of Liberty he is falling in slow motion yet the cars down below are driving around in real time.
Continuity mistake: When Dredd and Fergie are fleeing, as the approach the dead end, you see the bar sign in front of them, on the right, which they start to pass when the taxi crashes. In the next shot, they pass it again, but in the next shot after that, the bar sign is once again in front of them.
Continuity mistake: The final battle inside Liberty's head - Rico tries to escape on his Lawmaster motorcycle. Dredd pulls Rico off and the Lawmaster plummets to the ground. Seconds later when they show a slow motion shot of Rico falling to the ground there is no wreckage whatsoever of the Lawmaster beneath him.
Answer: The facility only ever cloned Rico and Dredd. It had never been tested at max capacity. The equipment was also 30 years old and Rico tried to birth the clones early which the system wasn't designed for. The stress of all these things added up to destroy it.
Grumpy Scot