The Oldest Rookie (1987)

Ike Porter is a cop who not long after graduating from the police academy was assigned a desk job and in twenty five years that is where he has been and eventually rose up to the rank of deputy chief but has never really had any field experience. After a friend of his dies, Ike decides that he wants to be a regular cop. So he has to give up all the privileges that his rank gave him and has to go through the academy again. And after graduating he is assigned to Officer Tony Jonas a young cop. Now Tony tells Ike that street cops are considered insignificant and that detectives are the ones who get all the praise, and when Ike suffers this degradation, he calls in some favors and has him and Tony appointed detectives. But their commanding officer Lt. Zaga and another detective Lane doesn't think that they should be detectives so they make life tough for Ike and Tony but they nonetheless persevere.