Continuity mistake: When Jim and Jack are in the morgue, and Jack says, "Is there anything else you like to comment on?" the doctor is standing next to Jim writing something down on a pad or piece of paper (you can see the pencil), but in the following shot he is not writing on anything and his hands are behind his back.
Continuity mistake: Close to the end of the movie when Jack Cole is riding in the car with the two Russian mafia guys, one of the guys says "Coldest winter I can remember in L.A., the wettest too." The guy puts his hand up to adjust the rear view mirror, and then puts his hand down; in the following shot, you can see he puts his hand down again.
Continuity mistake: At the end of the film we see Jack have a fight with Donald. Then Jack says " If thats the best you've got, I'm just going to have to kill you". Then Jack grabs Donald around the neck with both hands, but when the camera changes to behind Donald, Jacks hands are not around Donald's neck.