Striking Distance (1993) on Netflix

Tom Hardy comes from a family of cops and has just broken the cardinal rule -- never speak out against another cop -- which now makes him persona non grata with the other cops. Presently there's a serial killer on the loose and when Tom and his father and some other cops corner him, a big chase ensues and when it is over Tom's father is dead, supposedly killed by the perp. Later a suspect is brought in whom Tom doesn't believe is the one but most of the cops just don't want to believe him or think that his objective is clouded. Eventually he is drummed out and the only position he could get is at river rescue. Two years later he still sticks to his beliefs and apparently the killer is back but nobody believes him and some people think that he is copy-catting the killer.