Continuity mistake: When the fireboat brings Eastwood and Daly out to Alcatraz, Eastwood uses the fire hose against a bad guy in a tower. As Eastwood prepares his hose attack, there are close up shots showing Eastwood turning the hose mount from his right to left, and long shots showing Eastwood turning the hose mount from his left to right.
Continuity mistake: In one scene, the mayor of San Francisco and his aide go to a Giants baseball game at Candlestick Park. When the mayor & the aide are seated and having a conversation, a young man siting a row or two behind the mayor leans slightly forward, looks directly into the camera, and starts smiling and waving.
Revealing mistake: When the armed gang abduct the Mayor, a LAW rocket is fired at a Lorry, the few seconds are obviously several shots pieced together. The giveaway being the driver is a dummy as the driver has no face, even after the explosion, the faceless dummy just falls out of the cab.