By-The-Book Cop

""I was guilty as sin, but Valentine couldn't prove it. And he was the rarest breed of law enforcement officer: the type who knew I was breaking the law, but wouldn't break it himself to bust me.""

- Yuri Orlov, Lord of War

""Police work is as much about preventing crime as it is about fighting crime. Most importantly, it is about procedural correctness in the execution of unquestionable moral authority.""

- Nicholas Angel, Hot Fuzz

The By-The-Book Cop is a stock character in police shows and crime fiction in general. They're the older (and usually whiter) cop, who believes in following the law as it is written, playing by the rules even when the criminal scum they're after does not. A stickler for procedure, the BTBC is quick to chide their rookie partner for playing fast and loose out in the streets, and when they're Da Chief, you'll see them constantly threaten to suspend the loose cannon for their impulsive heat-of-the-moment shoot-first-ask-questions-later behavior. If they deem that the situation warrants it, they may bend the rules slightly, but they'll never go so far as to break them; they are, after all, honest and incorruptible.

Often the complete opposite of a Cowboy Cop, with whom they are often paired to form an Odd Couple. If a Good Cop, Bad Cop dynamic forms, they tend to be the good one. Police officers who appear in the Police Procedural tend to be uniformly this type of cop, due to the relative paucity of cowboy cops in Real Life.

Anime and Manga

 * Togusa in Ghost in the Shell used to be a regular cop and sticks very close to the rules to seperate himself from the masses of corrupt cops. In the counter-terror unit Section 9, he is the rookie and painfully out of place, as they usually deal with people who have the courts at their call. To his superiors, the laws are merely a "suggestion" for how to achieve justice and safety.
 * Inspector Zenigata of Lupin The 3rd, quite possibly the world's most honest cop.
 * Kuroko Shirai from To Aru Majutsu no Index franchise.
 * Bleach: Soi Fon is the head of the Keigun (lit. "punishment force"), which enforces the laws of Soul Society and detains or assassinates violators. She's a stickler for proper procedure and follows the law to the letter, no exceptions.

Comics

 * Commissioner Jame Gordon from Batman, if it was not for his frequently calling upon the services of an unofficial masked vigilante to help police his city. Batman: Year One, The Long Halloween and Dark Victory track his growing relationship with Batman and rising position in the Gotham City Police Department, and they all reiterate his commitment to Law & Order and refusal to compromise his integrity and the rules, even to convict criminals he knows are guilty.
 * He slips once when The Joker was on death row for a crime he might not have committed . He suggested to Batman that they let Joker fry despite the possibility that he's innocent of this particular crime. Batman tells Gordon that he's going to pretend he didn't say that, and the matter is dropped.
 * Gotham Central is a Police Procedural focusing on the Major Crimes Unit of the Gotham City Police Department. Each member of the MCU is hand-picked by the Commissioner of Police in order to insure their integrity and commitment to honest police work, and the series follows them as they try to act honorably in a police department filled with corruption and graft.
 * The title character of Judge Dredd is about as extreme as this trope can get. However the the character does grow to question the law every once in a little while, notably just before the "Necropolis" arc and the ongoing issue concerning mutant rights.
 * There are also numerous minor aversions to this trope where Dredd himself brings up that part of being a Judge is using ones own discretion, meaning he occasionally ignores minor crimes or makes allowances for mitigating circumstances. Just like a real cop, only less often.

Film

 * Eliot Ness in The Untouchables.
 * Osmosis Jones. Drix is the BTBC, Osmosis is the Cowboy Cop.
 * Sergeant Roger Murtaugh in Lethal Weapon, at least initially.
 * All of the Beverly Hills cops in Beverly Hills Cop, except Axel.
 * Lieutenant Bogomil actually invokes the trope name when he explains to Axel why he won't let him investigate a customs bonded area without a warrant after discovering coffee grounds in the building.
 * Deputy Police Chief Dwayne T. Robinson in Die Hard.
 * Nick Angel in Hot Fuzz. Even after defeating the villains Cowboy Cop style he still does paperwork.
 * The Ontarian Martin Ward is the By-The-Book Cop in Bon Cop, Bad Cop. You have one guess as to what his (Québecois) partner is.
 * Jack Valentine in Lord of War follows by the book and is the only reason Yuri Orlov was able to get away for as long as he did.
 * Lt. Ed Exley in L.A. Confidential..
 * Inspector David Tosci in Zodiac is very by the book both in life and in the film. The film shows all the steps he goes through while pursuing a key suspect in a pretty fair aversion of Hollywood Law, and even in the end he knows there's no smoking gun to prove the killer's identity.

Literature
"Daniel [disgustedly]: The law is the only moral code you ever need. You're always so sure about everything. Kate: I'm sure about some things. I'm sure about murder. How can I not be?"
 * Geoffrey Briggs, Da Chief of the NCD in Jasper Fforde's Nursery Crime, always does things by the book... the crime fiction book, that is. He habitually suspends the detective once in every case for intentional dramatic effect, and trains his cops for the job by making them watch reruns of Columbo.
 * In P D James comparatively realistic Adam Dagliesh series, Kate and Dagliesh both fit this trope well. When Daniel, the third member of the squad, lets a suspect commit suicide rather than face prison, it really shines through. Daniel is disgusted by their (especially Kate's) belief of absoluteness the law, and they actually have an intelligent conversation about it. Paraphrased a little:


 * Who Censored Roger Rabbit? (Literature)?: Toon police Captain "Clever" Cleaver, working on the Rabbit murder case doesn't want any loose cannons (e.g. Eddie Valiant) wrestling the long arm of the law away from him. In the not-quite-sequel Who Plugged Roger Rabbit?, Sargeant "Bulldog" Bascomb takes a similar role, but somewhat more similar to Da Chief. (though Cleaver is still mentioned as the one who habitually hounds Eddie).
 * Captain Carrot of Discworld, the Literal-Minded adoptive son of dwarfs, who is so consistently Lawful Good that it even rubs off on the otherwise deeply cynical city of Ankh-Morpork.
 * "The Book" in this case being The Laws and Ordinances of The Cities of Ankh and Morpork, published some six generations previously. Carrot isn't just the only copper who follows the book, he's probably the only one who's read it, since the equally Lawful Good, but much more pragmatic, Commander Vimes got the Librarian to hide it because it was just causing trouble.
 * The In Death series. Eve somehow manages to be both this and a Cowboy Cop! Peabody is a straighter example of By-The-Book Cop but not entirely.
 * Sano Ichiro, in the series bearing his name, is an interesting twist as he is also a Samurai. Unlike many of his compatriots, he actually follows the code of Bushido and is an honest man.

Live Action Television

 * Alien Nation: George Francisco.
 * The X-Files: Not quite a cop, but a similar example: Director Walter Skinner of the FBI likes things clean and easy, with Mulder and Scully turning in matching reports, preferably with no mention of aliens, mad science, or miscellaneous monstrosities. In a way Scully herself plays stern By-The-Book Cop to Mulder's enthusiastic cowboyesque shenanigans.
 * Skinner is no stranger to cowboyish attitude but he is also perfectly aware how dangerous is the environment he is moving in.
 * The real BTBC here is Doggett, who actually got his start as a cop. Once you get over the fact that he replaced one of the most beloved characters in the series, the poor fellow's attempts to adapt from his world of by-the-numbers L&O to the weird and wacky world of the X-Files can be somewhat charming.
 * Peter tries to be this on White Collar, but Neal's brilliant-but-not-quite-legal schemes make it hard for him. More often than not he ends up looking the other way, or even helping Neal, if he knows it means catching the criminal.
 * The Dakotas: Ragan is the perfect example of this. The show is set in the Old West, and Ragan believes that deviating from the law in any way devalues it.
 * Odo in Deep Space Nine is from a species that has by the book as its hat. As the head of law enforcement on the station, he does have mercy with people who meant no harm or acted out of desperation, but that does not stop him from taking loitering children to his office and calling their parents to get them.
 * Due South: Mountie Benton Fraser. Not just that, he goes by a completely different book than people might expect.
 * P.C George Dixon of Dixon of Dock Green is a British example.
 * The police officers on shows like Law and Order and Homicide: Life On the Street, at least in their earlier seasons, generally tended to be this sort of cop; they might not have been quite the 'friendly police officer' of earlier tropes, but they generally tended to do their jobs following procedure.
 * With a rather lax interpretation of the Bill of Rights, however.
 * Just about every police officer in a Jack Webb production. When an exception shows up, it's usually the main characters who have to catch or stop him.
 * The The Good Guys has Jack Bailey who is extremely by the book but pisses off his superiors so much that the only way he can solve the case is to follow the lead of his Cowboy Cop partner.
 * Detective Elton Hodges has been filling this role in a very by-the-book fashion as Jack has become more and more influenced by Stark.
 * Sam Tyler in Life On Mars and Alex Drake in Ashes to Ashes are the BTBCs to Gene Hunt's Old-Fashioned Copper. DCI Jim Keats in Ashes to Ashes is a villainous BTBC example.
 * In Freddy's Nightmares, the cop who arrested Freddy Krueger but forgot to sign a warrant was actually one of these, and frowned upon the idea of the parents of Springwood getting together and administering justice on Freddy themselves when the case against him was dismissed.
 * Rob Hollins in Doctors.
 * FBI example: Agent Hotchner in Criminal Minds, although he did have a bit of a breakdown at one point that led to him.
 * The Shadow Line:
 * Jonah Gabriel gives the impression of one at first, though he has cowboyish traits like his refusal to obey his superiors' wish that he stop investigating Harvey Wratten's death and he's hinted for a while to have been an actual Dirty Cop before he lost his memory.
 * Robert Beatty, though he's a customs officer rather than a cop.
 * A minor example appears in the first scene of the series, with the rookie that points out all the procedures Sergeant Foley violates at the scene of Harvey Wratten's murder.
 * Community parodies this in "The Science of Illusion" when Annie and Shirley become temporary campus security guards. They end up getting into an argument about which one of them should be the By-The-Book Cop and which one should be the Cowboy Cop despite the fact that both of them are equally suited to both roles, and Genre Savvy Abed, who is following them around, ends up invoking a whole load of tropes based on this.
 * Detective Abby Kowalski from Against the Wall.
 * Rookie Blue has Chris Diaz as the most By-The-Book Cop amongst rookies. Actually detrimental to his performance as he does not take initiative which is noted by his superiors.
 * Signalman from Gekisou Sentai Carranger, oh so very much. Played to the hilt for laughs, of course.
 * Sky from Power Rangers SPD. Constant head-butting with the much more laid-back Jack, naturally.
 * The CSI franchise can both play this straight and subvert it. Brass in original CSI and Mac in CSI: NY are usually very by-the-book. But, lately, Mac in particular, and Brass to a smaller extent will break rules if it comes to it.

Radio

 * Joe Friday from Dragnet, especially in The Movie.

Tabletop Games

 * In Feng Shui, the By-The-Book Cop is usually a Karate Cop. He may bend the law to serve higher justice, but only if he has no other choice.

Video Games

 * Katsuya from Persona 2 is by-the-book to a ridiculous degree, even in supernatural situations where the law shouldn't really apply. (In a reversal of the usual way of this trope, he's quite young; his rule-breaking, dubious-method-using foil, Baofu, is much older.)
 * Citadel Security (C-Sec for short) in Mass Effect is apparently made up of nothing but By The Book Cops, if the player is to believe their leader. The outwardly-reserved Cowboy Cop on your crew split with the force over increasing frustration with C-Sec's regulations; Commander Shepard has the option to either encourage him in his Cowboy Cop behavior or convince him of the value of doing things by the book.
 * Of course, in the second game a C-Sec officer admits during Thane's loyalty mission that he's been looking the other way of a certain criminal as long as he "buys tickets to the C-Sec charity ball." The same cop will later, although that's shown as an act of compassion. Overall, not exactly a Cowboy Cop, but he's certainly breaking a few rules at this point.
 * Norman Jayden from Heavy Rain, whose by the book-ness naturally puts him at odds with Cowboy Cop Lieutenant Blake.
 * Your squad in SWAT 4, the best score will be awarded to players who follow this trope--handcuff and report all suspects and civilians, subdue suspects with non-lethal methods and bring them in alive unless they're openly hostile, and confiscate all firearms and other evidence.

Visual Novels

 * Edgeworth is a by-the-book prosecutor (which is almost the same thing as a cop in this universe) in Ace Attorney Investigations. He goes by the rule of evidence, even when someone's guilt is blindingly obvious. In the first game, pre-Heel Face Turn, he is a little less ethical.
 * One might file the judge under this trope. He responds only to presented evidence and testimony, despite his senile appearance.
 * Detective Gurski from the Murder Mystery Visual Novel Jisei spends most of his time guarding the crime scene and making calls to get a background on the victim. He will not hesitate to arrest you if he manages to see you trying to get another look at the body. However, he does defy this trope by encouraging the protagonist to do most of the questioning on his own.

Web Original
"Perfect Partners: After Danny Rizzo loses yet another wisecracking maverick partner to an explosion, he dreads being paired up with still another loose cannon who gets things done. Instead, he gets James Flynn, a cop who likes to do everything the same way he does. When they find themselves reading suspects their Miranda rights in unison, they know this partnership was meant to be. Together, they hit the streets and play it safe, steering responsibly away from things outside their jurisdiction and always calling for backup. The film follows their careers together, traffic stop after traffic stop after noise complaint, until the last day before retirement. They arrive to find a suspiciously empty office. Sensing something is wrong, they hurry to the chief's office, where the whole department surprises them with a party, and the chief winkingly tells them they can head home a day early and count it as a free "sick day" on him. After retiring, they move to Florida with their wives."
 * Used as a positive in Cracked.com's list of Movie Characters that didn't make horrible decisions

Western Animation
"Fillmore: You're always by the book. Wayne: You threw out my book."
 * Police Chief Suarez, Frida's father, in El Tigre.
 * From Fillmore: Wayne Ligget, Fillmore's old partner, was said to be the good cop to Fillmore's Cowboy Cop.


 * Flint in G.I. Joe: Renegades is this. Although he starts to suspect Duke's innocence of the crime, he still wants to bring him in if only to get to the bottom of things.
 * Ellen Yin, in early episodes of The Batman, was like this, determined to arrest Batman (as well as the villains of the week) for being a vigilante and acting outside the law. Her narrow viewpoint gradually became less black-and-white, however.
 * Zachary Foxx in Adventures of the Galaxy Rangers defaults to this, and was much more "by the book" at the start of the series. His more "colorful" Badass Crew sometimes rubs off on him, though.
 * Teenage Mutant Ninja Turtles 1987 has the Shredder's brother.

Real Life

 * Chilean cops are generally this, especially the young ones fresh out school. Don't ever, EVER, try to bribe one to get out of a ticket. Lie, cry, say your mother is dying, but do not try to bribe the cop. This is even mentioned in tourism information about the country.