First episode featuring Ed Marinaro as Officer Joe Coffey.
Steven Bochco makes a cameo as #3 in the police lineup.
In the scene where Esterhaus and Hunter chat over coffee, Hunter is drinking from a cup labeled "Calletano," indicating it's Lt. Calletano's.
Joyce Davenport hands Captain Furillo two tickets to a baseball game saying "the Phillies are in town". Meaning the show occurs in a midwestern national league city as there wasn't inter league play at the time. This removes Detroit, Buffalo, and Cleveland as host cities. It also removes Milwaukee as a possible host city since it was an American League city at the time Narrowing the choices down to Cincinnati, St. Louis or Chicago