Visible crew/equipment: When asking the street gang in the street war sequence to drop their weapons ("I am the law") you can clearly see the cable the microphone is connected to running from the back of Stallone's helmet. This cable is not visible before or after.
Visible crew/equipment: When Dredd is done judging the motorist, blows the car up, and says "Happy motoring!" the squad comes to arrest him. When the camera is looking at him, you can see an overhead camera rig reflected in his visor.
In one of the final scenes where Stallone is hanging out of the Statue of Liberty, you can see that his "JUSTICE TATTOO" on his upper arm is a fake. You can see at the edge of the tattoo that it is glued on the skin.