Continuity mistake: In the first scene of prison violence, babyfaced bully Semyon grabs a guy's head and smashes it on the table. In the close-up we see the foot tray bouncing off, pieces of lettuce fly and a clanging noise is heard. And yet, after the cut nothing happened, the tray is still in front of the poor victim, not a piece of bread out of place, nothing spilled on the table. (00:15:30)
Continuity mistake: When he fights Chuck Lidell, he is wounded on the right side of his body. During a scene when he is lying on his side, the wound has moved to his left side and then magically reappears back on his right when he stands up.
Factual error: The good guys manage to take over key parts of the prison by homebrewing some chloroform mixing alcohol and bleach in a cute little spray bottle, crawl through the ventilation system and slip in the room a couple dainty squirts. Which instantly knock the guards (one of them with a full face helmet) out. All of this is of course bahooey; chloroform is really volatile and would never make it across the room, and the dosage is absolutely negligible. If the gas were this powerful (which is not) would have KO'd the two agents anyway while they were doing this chemist stunt preparing the gas itself in the tiny broom closet.
Factual error: The protagonist is serving time in a federal prison, but he regularly sports a bracelet with a very long string, complete with an anchor-shaped pendant super-easy to weaponize (he never does in the movie, being a good guy!) and going pretty much against every regulation.
Factual error: Throughout the movie Danielle Chuchran wears full makeup (lipstick, eye-shadow, even mascara) despite being a prisoner. All the other female characters wear no make-up at all (or if they do, it is completely inconspicuous). It should also be noted that she is an outcast that is on the wrong side of the people who run the joint, the fact that she's the only one dolled up makes no sense other than for the very non-plot related reason that she is the deuteragonist, 'good guy' and gets close-ups.