Rabid Cop

"FBI Agent Norman Jayden: Blake, you are an unbalanced, psychopathic asshole!

Lieutenant Carter Blake: I'll take that as a compliment."

- Heavy Rain

""I'm supposed to read you your rights. But you're in Mooney's jail...and you ain't got no rights.""

- Officer Curtis Mooney, Killer Klowns From Outer Space

The room is small. Help is far away, on the other side of many locked doors. Your arm is chained to the table and a Rabid Cop is spraying spittle into your face in a way that convinces you that he has completely lost his mind.

All he wants you to do is admit that everything Hitler did was your idea. Sounds good to you. What do you have to sign to get away from this maniac?

The Rabid Cop might be casually dirty, or overbearingly self-righteous, or anywhere in between, but they all have two things in common: a reckless disregard for civil rights, and an unwavering conviction that any person they've identified as "the perp" really is a perp (regardless of any contradicting evidence) and deserves to suffer. Rules and trials are for the PERMISSIVE LIBERAL ASS-WIPES! In a Good Cop, Bad Cop routine, they usually take the "Bad Cop" ball and run clear out of the stadium with it.

Compare/contrast the (presumed) sympathetic Cowboy Cop.

Film

 * Although he isn't in the circumstance described above, Alonzo Harris from the film Training Day is the embodiment of this trope. He is not necessarily insane though, just genuinely evil and sociopathic.
 * Dennis Peck from Internal Affairs ...see Alonzo.
 * David Kujan pulls this on Verbal Kint a couple of times in The Usual Suspects. ("I've got immunity now." "NOT FROM ME! There IS no immunity from me, you piece of shit!")
 * Most of the Perp Sweating scenes in the South Korean film Memories of Murder, which is based on real events, fall into this category.
 * Bud White of L.A. Confidential, hands down...to the point he frightens the officer trying to play 'bad cop', as well as the suspect.
 * "ARE YOU USERNAME 'LADIESMAN217'?!?!"
 * The main character's partner is one of these in Bad Lieutenant Port of Call New Orleans. And the main character starts to turn into one himself as his addictions spiral out of control.
 * Officer Mooney in Killer Klowns From Outer Space has to be almost physically restrained from beating up a couple of punks brought in for public drunkenness. He later takes a flashlight to the head of one of the klowns, which turns out to be not such a hot idea.

Live Action TV

 * As illustrated above, Andy Sipowicz from NYPD Blue.
 * Before Andy Sipowicz, there was Mick Belker on Hill Street Blues. Dude even barked and growled like a rabid dog.
 * And, lest we forget, bit people on a regular basis.
 * Law and Order Special Victims Unit's Elliot Stabler can cross into Rabid Cop territory, especially when It's Personal. Which is roughly every other week. This tendency earned him the Fan Nickname Un-Stabler.
 * Most likely because Elliot is increasingly unstable and psychotic. That series will NOT end until he actually kills someone, ending his massive fall from grace.
 * The cop in the (ironically named) "Unstable" made Elliot look normal.
 * Most of the 1973 detectives in Life On Mars are rabid by today's standards, especially in contrast to 2006 transplant Sam, but Gene Hunt deserves a special mention, here.
 * While he is a proponent of the Jack Bauer Interrogation Technique, Vic Mackey on The Shield only rarely turns into the rabid cop - usually, his menacing is done with a cold and calculating air.
 * Jack Regan of The Sweeney got rabid at times, too.
 * Peter Boyd of Waking the Dead tends to get EXTREMELY SHOUTY and verges on violent at times, though usually one of his team is watching through one-way glass and bursts in to stop him.
 * Jack Malone of Without a Trace can be pretty worked up and he will do anything to get information on on those poor missing people.
 * Jimmy Beck in Cracker, once causing his superior officer to say 'I don't know what you did to him, but you scared the hell out of me.'
 * Several police on The Wire, but standout examples are Anthony Colicchio, who attacks a middle-school teacher for asking him to move his police car, and Eddie Walker, who breaks a teenaged carjacker's fingers just for giving him additional paperwork.
 * The retired detectives of New Tricks have slightly Cowboy Cop attitudes compared to modern police methods and standards. So they see nothing wrong with creating a fake Rabid Cop scenario where the interrogator gets so insanely angry that he shoots the suspect's public defender lawyer. The 'lawyer' is another retired cop and the gun is a starter pistol.

Literature
""Who watches the watchman? I do.""
 * THAT! IS! NOT! MY! COW!. Vimes does whatever he can not to turn into one, to the point that he


 * Averted in The Dresden Files book Changes. Rudolph tries his best to play the Rabid Cop, but all his desk-pounding and spittle-flecked screaming manages to do is cause Harry to crack up and the other interrogator ends up ordering him out of the room. It probably helps that Harry has seen Rudolph freak out whenever confronted with the sort of thing he deals with all the time.
 * Stephen King's Desperation: Collie Entragian. Of course, I'm going to kill you not all he seems, I'm going to kill you this being a Stephen King novel. I'm going to kill you.

Video Games

 * Lt. Carter Blake is the epitome of this trope taken to its highest form. He's a police officer with immunity from the local precinct (why, nobody knows) who prefers beating a suspect rather than extracting any information, has no problem with breaking the law in order to investigate, and will have no qualms about killing. Initially, he's rather reserved to just beating suspects,
 * It doesn't stop there. One possibility at the end of the game has Blake  Needless to say, Blake is by far the most hated character in the game, even the actual killer doesn't come close. The worst part? In any good ending he gets away with everything.
 * Yeah, about him getting away in the end, he doesn't because he isn't mentioned in the news.
 * There's a bright side: he doesn't in the bad endings. . Sweet justice.
 * There's a lot of back-and-forth about whether Saren Arterius of Mass Effect is a Complete Monster or a Well-Intentioned Extremist, but he really fits this trope better than either. As a Spectre, he's essentially a Council space cop with no strings attached, and he plays it to the hilt - making frequent usage of the Jack Bauer Interrogation Technique, pursuing his own ambitions on the side and pinning the collateral damage on people he doesn't like. He's the same sadistic, racist government law officer we've seen in many other works - just relocated to a sci-fi setting.
 * Agent Nightingale in Alan Wake really fits in this trope. Though the source for his jerkassery is found in his back story.

Western Animation

 * This is parodied in The Boondocks where a Rabid Cop violently accuses and assaults Butt Monkey Tom Debuoir for a crime that he obviously didn't commit before being forced out by the nice cop. He then rushed in 5 seconds later to assault Tom again.
 * The titular character from the Adult Swim show Assy McGee is an extremely violent parody of a Rabid Cop (and a Heroic Comedic Sociopath) despite being, as his name suggests, a pair of ass cheeks.
 * Iron Man: Armored Adventures gives us their take on the NYCPD and the inexplicability of Family-Friendly Firearms at the same time. Doppelganger!Tony has just shot at unarmed people at a party with a laser gun and rushed off. The real Tony Stark is taken in for questioning, and one of the officers is like this, complete with banging on the table and yelling, "Did your friends give you the lasers?!"
 * Though not technically a cop, Lock-Up from Batman: The Animated Series definitely counts.