Over the next two nights, this "Maniac Cop" commits more murders, prompting Lieutenant McCrae, who was told by his superiors to suppress eyewitness accounts that the killer was wearing a police uniform, to pass on information to a journalist, in an attempt to protect civilians.

This causes panic and dissent among the city, and results in innocent patrolmen either being shot to death or avoided on the streets by people afraid of them being the Maniac Cop.

Ellen Forrest, suspecting that her husband Jack may be the Maniac Cop, follows him to a motel and catches him in bed with fellow officer Theresa Mallory.

Hearing the commotion, Jack and Mallory leave the interrogation room and find the corpses of numerous officers strewn about the halls of the building.

During the 50th annual Saint Patrick's Day parade, Jack waits outside as Mallory warns Commissioner Pike and Captain Ripley about Cordell, but the two refuse to believe her and have her arrested.

[2] The film was first released on DVD on April 8, 1998, by Elite Entertainment and included a commentary by director William Lustig, writer Larry Cohen, star Bruce Campbell, and composer Jay Chattaway as well as a trailer and deleted scenes.

[11] Reviewing the Blu-ray release, J. Hurtado of Screen Anarchy wrote that despite its faults, Maniac Cop deserves mention as one of the last exploitation films set in New York City.

[13] Bill Gibron of DVD Talk rated it 4.5/5 stars and called it "one of the era's finest forgotten gems", deserving of a critical reappraisal.

[15] Gareth Jones of Dread Central rated it four out of five stars and called it a cult film that is "amongst the cream of the crop of late-eighties low-budget horror".

[16] Bloody Disgusting rated it five out of ten stars and questioned why the film has a cult following when it has a poor script and direction, uneven tone, and boring kills.

[20][21][22] In October 2019, HBO and Canal+ picked up a Maniac Cop TV series that will be executive produced by Nicolas Winding Refn, through his production company by NWR Originals, and John Hyams, who will also direct the pilot.

[24] The Maniac Cop film series and Robert Z'Dar were mentioned in the song "Two Trucks" by Internet comedian Neil Cicierega.