Tony Scali was supposed to be in his late 30s. Michael Chiklis was actually 28 when cast as Scali, in part because he looked much older than his real age. When Chiklis lost weight during the course of the series, the network, fearing that such weight loss might negatively effect the ratings, reportedly had Chiklis stuff his clothing to appear older and heavyset, and also discouraged him from shaving off his hair to look still older. Chiklis claimed he ran into problems later in his career when casting directors assumed he was much older than he actually was because of the show.
Creator Steve Kronish wanted to cast Michael Chiklis after working with him on Wiseguy (1987), but CBS rejected him because they felt Chiklis was too young for the part. Kronish took the idea to ABC, who was convinced to cast Chiklis after seeing him in the failed ABC pilot Maverick Square (1991).
Like the previous series 21 Jump Street, the series was filmed in Vancouver, British Columbia, Canada.