I saw this movie on HBO in the early 90s.  It was a cop movie, I think set in California with an Hispanic police chief. A cop was killed by criminals and his partner and the rest of the force are out to get the gang behind it.  During a police meeting, the chief tells the cops that it’s hot out and to be sure to drink enough water.  A cop asks the chief if the criminals they can assume the criminals they are out to get are working alone.  The chief replies “You’re a cop, you don’t assume anything.”  That’s all I can remember.