Narc (2002)

Oak gears up to interogate the two dealers but Tellis intervenes. He confronts Oak with the information he's accumulated and accuses him of killing Calvess himself. He goes to call backup when Oak holds him at gunpoint and disarms him, then hits him with the stock of his shotgun. Oak goes back inside and brutally attempts to force the two gangbangers to admit they killed Calvess. Outside, Tellis manages to break into the cruiser, get a pistol, and call for backup. He re-enters the warehouse to see Oak holding the two dealers at gunpoint. He orders Oak to step away, and just as Oak is about to pull the trigger, Tellis shoots him twice. As he is dying, Oak reveals that he was present when Calvess was killed, but it was Calvess that opened fire on the fleeing dealers. Oak confronted Calvess and tried to get him to go to rehab, but Calvess chose to pull the trigger on himself. Calvess was his own killer. Oak dies soon after revealing this information, but his confession is captured on the tape recorder.

Agent Neuman