Goofs

When Duvall is explaining his mathematical justification of why he believes the assault is warranted, he states that there are eight people inside the building, but at the time, he had no way of knowing how many people were inside the building, and this is verified later on when he asks Alex to tell him how many people are inside.

Other than the prisoner transfer bus on its way to Precint 13, no other vehicles are shown to have any traction problems on the snow-covered roads.

Capra is still wearing the handcuffs when he and Iris drive off in the SUV, but after the crash, the cuffs are gone.

During the initial sequence of lasers and shots aimed inside the station, characters close the Venetian blinds. However, in subsequent shots, the blinds are open again.

The camera zooms in on the bus right after the pill drop scene 1 hour and 20 minutes into the movie, the fire has been burning for some time in the bus but there is still snow covering the roof of the bus. The heat from the fire would have melted the entire roof at this point.

The Detroit Police Department does not have the rank of captain. Duvall should have either been a lieutenant or an inspector.

There are no holding cells in the basement of any of Detroit's precincts.

In the closing scene there are no tire tracks in the fresh snow for the ambulance.

The "pills" that Roenick shows us more clearly near the end of movie are clearly Icebreakers mints. You can even see the little blue "flavor capsules" in them.

Many of the weapons used show no operation and shell ejection, making it obvious that they are simple rubber replicas with muzzle flash and sound added on in post-production.

When the SUV flips over after having its tire shot out, a stuntman's elbow pad is visible in the window of the SUV while it is turning over.

Just after Roenick pulls the doc back from the front door after she tried to leave on her own: The lasers lines veers back and forth in much wider angles through the windows than would be coherent with the shooters being so far away that the story indicates. There's even some darting in a very steep angle upwards indicating that the shooters would be sitting few meters away from the building.

After Roenick comes in from the fight he had with the guy in the bus, he has a bloody lip. After this point, it appears and reappears through out the movie, until it eventually is gone altogether.

Towards the end, those small cans had a lot of fuel in them.

When the camera is behind Beck while he is talking to Jake through the bars, you can see that his mouth talking but there are no words. This is right before you says the second "You!"

When Anna and Doctor Sabian are fleeing in the car, someone appears in the backseat and shoots Anna who is driving but leaves Dr Sabian alive. The car then crashes as Anna is dead. The better option would be to kill Dr Sabian and take Anna, the driver, prisoner.