Continuity mistake: When Portnow meets with Bishop at the church, in the first closeup of Bishop's crossword puzzle the word "MUD" is the second word across at the top, and at the center of the puzzle the 4-letter word "GEAR" is written in the 5-letter answer - with the fist space left empty. However, in the next closeup of the puzzle, now the word "ETA" is the second word at the top and "MUD" is the third, and the word "GEARS" has the "S" added, with the letter "G" started properly in the first space of the answer.
Continuity mistake: Sgt. Roenick's facial hair changes throughout the movie. Most of the time it is seen as a scruffy moustache and goatee, several days worth of growth. But in the scene where he tells the prisoners the precinct is under attack by rogue cops, he is practically clean-shaven. And during the scene in the forest, he is sporting a five-o'clock shadow instead of the usual goatee.
Continuity mistake: When "8 months later" appears on the screen, we see Jake's nightstand with only one framed photograph near the lamp as the camera pans to the right, but in the next wideshot that photo has moved to the front of the lamp and two more framed photos have suddenly appeared.