Police Academy 4: Citizens on Patrol is the fourth comedy film in the Police Academy series. It was released in 1987 and is the sequel to Police Academy 3: Back in Training.
A group of Police Academy graduates are sent to train a group of newly recruited civilian officers. The original Police Academy cast reprise their roles in the film. Capt. Harris, not seen since the first installment, returns as the film's nemesis. In Police Academy 2 and 3, Capt. Mauser (played by Art Metrano) filled that role, but Metrano asked to be replaced for the remainder of the series after filming number 3. This was the last Police Academyfilm to feature Steve Guttenberg as Carey Mahoney. This film also stars a young David Spade, as well as featuring a brief appearance from pro skateboarder Tony Hawk as Spade's double in a skateboarding scene.