CSI - Auto Gun That Doesn't Recock
This is in the episode that Nick and Catherine are investigating an officer involved in a shooting in which the driver of a jeep shot himself. When Catherine picks up the dead guy's gun the hammer is not cocked. If the guy had shot himself, the gun would have recocked itself.
Editor's Note: I really had to clean up the grammar in this to make it look presentable. Please, let's keep it nice and neat.