-> "Don't worry about us, ma'am," Fix assured her, and winked. "Titania has already laid down the law. We've obeyed it. Not our fault if what she decreed was not what she wanted."

->"Translation," I said. "We got around her fair and square. She won't like it, but she'll accept it."
--> -- ''Literature/ProvenGuilty''

It's safe to say that society as we know it couldn't exist without rules. Without rules, [[MightMakesRight power would be the only source of order in the world,]] [[AsskickingEqualsAuthority either in terms of destructive capability]] [[ScrewTheRulesIHaveMoney or material resources]].

And like any tool that can be used for the common good, rules have the potential to be ''abused''.

Rules have power, and their ability to level the playing field can also be used to ''unbalance'' it in favor of whomever makes the rules in the first place. So what can you do? You can always break the law, but the more clever will figure out [[HoistByHisOwnPetard how to beat them at their own game.]]

There are two ways this can happen:

# The rules can hang you, but the rules can also save you. {{Obstructive Bureaucrat}}s and the like may think of the rules as a hammer to crush unworthy peons with, but the people who wrote the rules may have had other ideas: an apparently mean-spirited and arbitrary rule might have a reasonable exception buried in its text that the tyrants in charge [[HangingJudge prefer to conveniently ignore.]] Alternately, the roles may be reversed, and a villain who apparently has been caught dead to rights by the authorities finds a convenient loophole to wriggle through.
# The people who enforce the rules [[ScrewTheRulesIMakeThem don't necessarily follow them]]. They may imagine themselves to be a higher class or more noble or pious or whatever, but in the end it's all because of the badge they wear or the title they hold: they're just as fallible as anyone else, and if these people insist that there's not a single rule they've ever broken, they can be sent screaming into a VillainousBSOD if someone finds that one obscure rule they ''did'' break, or points out a rule that they would ''never'' want to follow. (The more sociopathic might instead be compelled to dispose of whoever pointed out this fact, all to maintain their perfect record. Never mind that there are rules against ''murder'' in every culture on the face of the globe.) Again, this can have a dark side, as a paragon figure can be transformed into a BrokenPedestal if someone brings to light some transgression in his or her past.

An easy way to subvert CantGetAwayWithNuthin'. See also ScrewTheRulesIHaveMoney. Compare ScrewTheRulesImDoingWhatsRight and ChaoticGood, where Lawful and Good are on opposite sides, and LoopholeAbuse. Any RulesLawyer often uses the first variant, and is afraid of somebody using the second on him.



!Examples of 1:

[[folder:Comic Books]]
* In one of the ''DonaldDuck'' comics, the Beagle Boys use many strange laws and [[LoopholeAbuse legal loopholes]] to get away with really stupid crimes (like stealing one certain kind of sandwich), just to piss off police and the judge. However, it backfires because the judge later finds other loopholes that make them guilty anyway (stealing that one kind of sandwich is not a crime... as long as you don't eat it before dusk).
* A large part of ''ComicStrip/KnightsOfTheDinnerTable'' is an ongoing Rule Fu duel between GameMaster B. A. Felton and RulesLawyer Brian Van Hoose. Brian usually gets the better of B.A., but when the campaign is on the line, B.A. pulls out a win.
* Being just about the living incarnation of LawfulNeutral, this crops up occasionally in ''ComicBook/JudgeDredd'', typically in someone trying to "catch" Dredd overstepping his bounds, [[BotheringByTheBook setting things up in a way that they annoy him into leaving them alone]], or doing things that are [[LoopholeAbuse legal by way of technicality]]. It rarely works out well for them, as Dredd [[CatchPhrase IS the law]], and is as adept with pulling up even ''more'' obscure rules and regulations to do the right (or, at least, legal) thing as he is with just shooting people in the face.
* ''ComicBook/TheTransformersMoreThanMeetsTheEye:'' During a meeting with an extremely unfriendly organic captain, who refuses to let the crew go down to investigate an abandoned settlement, Ultra Magnus manages to use the rules (which he knows every word of) to make the captain let them go down.

[[folder: Fan Fiction]]
* In ''[[http://archiveofourown.org/works/10731591/chapters/23783283 Echoes of the Past]]'', a principal threatens to expel a 9-year old Laurel for punching a bully, citing she signed a contract "not to harm" another student. She replies that contracts signed by minors aren't legally binding; and if they ''were'' he'd have to expel the bullies too, since while their bullying might not have physical, it was still harmful. The principal backs down.

[[folder:Films -- Animated]]
* In ''WesternAnimation/TheIncredibles'', Bob Parr (a.k.a. Mr. Incredible) works for an insurance company whose boss orders them to screw over the customers however possible; Bob gets around this by using CouldSayItBut to give the policy holders the information they need.

[[folder:Films -- Live-Action]]
* In ''Film/PiratesOfTheCaribbeanAtWorldsEnd'', Barbossa opposes Jack's motion to the Brethren Court (to fight the EITC's armada) by quoting the code, calling his motion "an act of war", something which can only be declared by the Pirate King, an elected official. But since each Lord of the current Court only votes for himself, it's unlikely there will ever ''be'' a Pirate King again. Barbossa even calls on [[LawfulNeutral Teague]], Keeper of the Code, to make sure this rule is enforced. Jack then calls for a vote, and when everyone else votes for themselves, Jack votes for the one Lord who supports his motion: Elisabeth. Jack gets his way and, since he followed the rules, no one can even complain. ''Kapow!'' Additionally, there's nothing in the rule that says the King has to be a man. Then again, Elizabeth is not the only female Pirate Lord present.
* Part of the plot of the kangaroo military court in ''Film/HartsWar''.


* Jesus versus the Pharisees in ''Literature/TheBible'', calling them out for violating other rules when they over-analyze laws (not helping people in need on the Sabbath going against why it exists in the first place). He also does it with Satan in the desert (If you walk off a cliff God will send angels to save you vs. You shouldn't tempt/test God).
* Happens frequently in ''Literature/TheIcelandicSagas''. Lacking a widespread writing system, law was taught orally; good knowledge of law earned a person great respect, although only a handful ever learned all the intricacies of the system. Courtroom scenes are common in the sagas, with knowledgeable people often playing key roles in the outcomes, to the detriment and benefit of both antagonists and protagonists.
* A minor plot point in ''Literature/ABrothersPrice'' is when the princesses have to decide who gets to inherit a piece of land, that is very strategically important, and use their rule-fu to make a ''legal'' decision that gives that piece of land to the crown. (They're benevolent rulers who adhere to their own rules). The three families who brought the case to court also try to invoke the trope to their personal advantage, and succeed to some degree, as the princesses only want the piece of land mentioned above, they don't care about the money, and manors, and other stuff.
* In Creator/IsaacAsimov's story ''Blind Alley'', a bureaucrat sets up a chain of events that allows a DyingRace of aliens to steal a fleet of spaceships and escape human space; the bureaucrat makes sure that there is an extensive (and legitimate) paper trail proving that he had nothing to do with it.
* From the Literature/{{Deryni}} works by Creator/KatherineKurtz:
** Kelson's CourtroomAntics in the treason and heresy trial of Alaric Morgan in ''Deryni Rising'' are this to a fare-thee-well. He stalls for time by having the charges read in full, then asks for each member of the Regency Coucil to vote individually, then he casts Morgan's vote for him (causing a tie), since he's still a member of Council until he's convicted. Jehana objects, then casts a vote against him since Kelson is presiding in person. Once Kelson hears the clock chime the hour and knows he's turned fourteen, he asserts "I rule today!" and appoints Morgan's aide Sean Earl Derry to the vacant seat (one of the members was killed in an ambush days earlier); this forces a tie vote and Kelson breaks the tie, freeing Morgan and insisting that any resubmission of the charges will require further proof. Jehana is not happy to be defeated by a suddenly-grown son: "Kelson had stood before the Council and defied her—not with childish threats and impotent taunts, but with decisive, adult action...now that Kelson was King in fact as well as in name—a development she hadn't even considered before—how could she possibly lure him away from Morgan's evil influence?"
** When Istelyn delivers Loris' notice of Kelson's excommunication and Interdict for Gwynedd to the king at Dol Shaia, Kelson reads it and loses his temper. While Morgan is simply unimpressed, having gotten used to being excommunicate himself (and being a [[SecularHero worldly by nature]]), Duncan calls the documents "worthless" and points out that Loris' reduced conclave of eleven bishops is insufficient to pass anything (canon law requires more than half of the twenty-two bishops to pass any such acts). Kelson scans the documents again, saying, " A twelfth. By God, you're right! How could I have forgotten?"
* Subverted in ''Discworld/MonstrousRegiment'': Jackrum pretends to pull this by citing a non-existent rule; Blouse later catches Jackrum out when checking the rulebook. Then does nothing about it, and indeed compliments Jackrum on the exactitude of his citation.
** This could be because he a) recognises on some level that Jackrum is very useful, b) also realises on some level that Jackrum could kill him in 2 seconds flat. It wouldn't be the first officer he's killed either.
** The situation proves that both Jackrum and Blouse are good and useful in their own ways. Jackrum because he defies the rules, and Blouse because he knows them.
* In David Brin's ''Literature/{{Uplift}}'' universe, the rules laid down by billions of years of galactic bureaucracy are extremely important. Even the most ruthless races are terrified of violating the "Standards for Acceptable Warfare."
* Used in ''Dexta'' when Gloria (professional bureaucrat that she is) pulls out every rule in the book to trip up the corrupt Imperial Governor. This gets her promoted to Acting Imperial Governor with deliberately impossible orders ("enforce a cease-fire between two alien factions without using Imperial troops to defend aliens"), so she takes advantage of a militia that the Emperor didn't know about to solve the problem.
* Happens frequently in Literature/TheDresdenFiles. The [[FairFolk fae]] cannot tell a lie, must keep any promise made three times, and must follow legitimate orders. As a result, rule fu is a way of life and an honored skill. When Harry pulls his donut with white frosting trick, the entire summer court laughs about it for months and his status goes up considerably. On the other hand, when he gains the authority to command Cat Sith, he quickly realizes that his rule fu is not up to the task, and he'd better stick to orders Cat doesn't mind following.
* By the same author, the ''Literature/CodexAlera'' books also feature a huge number of schemes and legal manipulation. ''Captain's Fury'' has one such example; SmugSnake Senator Arnos has ordered captain [[TheHero Tavi]] to execute civilians, arguing that they had committed treason by surrendering to Alera's enemies rather than fighting to the death against a vastly more powerful force that had no quarrel with them, and by the letter of the law he had the right to do so. He does this fully expecting that Tavi would refuse, and thus give the senator an excuse to accuse him of disobeying orders (and, by extension, treason against the Realm) and have him removed from office. Unfortunately, even after getting what he wanted, [[KickTheDog the senator refuses to repeal the execution order]], as he wants to MakeAnExampleOfThem to discourage any further "traitors". Tavi solves the problem by peacefully relinquishing his office but leaving Crassus (the son and heir of a High Lord,) in charge in his stead, knowing that Crassus would also refuse to carry out the execution order. If Arnos then accused Crassus of treason, [[PersonOfMassDestruction Crassus' father]] would have just cause to call Arnos to the ''[[DuelToTheDeath juris macto]]'' and [[CurbStompBattle "scatter the leftover pieces all over Alera"]], but if Arnos didn't deal with both "traitors" the same way, [[MortonsFork he would undermine the charges against Tavi]], leaving him little choice but to let the civilians live.

[[folder:Live Action TV]]
* ''Series/BabylonFive'':
** The episode "By Any Means Necessary" centers on a dockers' strike on the eponymous station. The government's negotiator refuses to give the dockworkers ''anything'' in their demands for more personnel and better safety equipment and then invokes the Rush Act, which authorizes Commander Sinclair to use [[TitleDrop "any means necessary"]] to end the strike. He does this obviously hoping for Sinclair to use military force and to crush the dockworker union. Sinclair decides to resolve things by moving funds from the station's military budget to meet the dockers' demands instead, which he couldn't do until the negotiator invoked the Rush Act.
** Sinclair tries this again in "Eyes", where he takes advantage of the rules regarding military intelligence inquiries. At first it seems to work, but eventually the investigator turns the rules in ''his'' favor, forcing Sinclair to change tactics.
** A really awesome instance was Delenn demanding that the whole Minbari Civil War (which the warrior caste had theoretically won) be hazarded in a SelfImmolation contest because [[GoodOldWays "It is the tradition of our people."]] which is what the warrior caste was arguing to return to as a pretext for starting the war.
** Sheridan pulls one off to temporarily delay the inevitable conflict between the station and [=EarthGov=] when Nightwatch pushes their weight around; General Hague reminds that he must follow the chain of command when it comes to the orders Nightwatch is demanding he follow, orders which everyone knows have come down from President Clark. Sheridan has Nightwatch personnel arrested because they've been running around boasting about how they don't answer to the military chain of command. Since Sheridan hasn't received any orders through ''his'' chain of command that he has to listen to them, they've tried to seize the station illegally.
* In ''Series/BreakingBad'', Junkyard Joe, the elderly owner of the salvage yard where Jesse has stashed the RV (and which Walt and Jesse are trapped inside at that moment) is particularly impressive in preventing Hank from searching the RV, which Hank knows could be driven away or destroyed the second it's out of his sight.
-->'''Hank Schrader''': I don't need a warrant, I have probable cause.
-->'''Junkman''': My understanding is that probable cause relates to something like a vehicle search.
-->'''Hank''': See those four round, rubber things? Those are wheels. This is a vehicle.
-->'''Junkman''': Did you actually see it drive onto the lot? I didn't think so. This is a domicile.
* ''Series/DoctorWho'': In "Paradise Towers", the Doctor escapes the rules-obsessed Caretakers by citing various 'rules' that he has just made-up. None of the Caretakers are willing to admit that they are so unfamiliar with the rulebook that they don't recognise these 'rules'.
* Just about every villain on ''Series/{{Leverage}}'' can't be caught by the authorities because they haven't technically broken the law - that's where Nate and his team come in.
* The fifth season of ''Series/NewsRadio'' features a three-episode arc where AffablyEvil Johnny Johnson successfully takes over Jimmy James' corporate empire. As a consolation prize, Johnny lets Jimmy take one WNYX employee with him as he tries to rebuild his empire. At the end of the day, Jimmy chooses... [[spoiler: Johnny, who had named himself Dave's replacement as WNYX news director earlier in the day. Johnny immediately recognizes the brilliance of Jimmy's move and concedes defeat.]]
-->[[spoiler: '''Dave''': But you're ''evil!'']]
-->[[spoiler: '''Johnny''': That's no excuse for poor sportsmanship.]]
* The ''Series/StarTrekTheNextGeneration'' episode "The Ensigns of Command" revolved around a human colony on a world claimed by the Sheliak Corporate. The Sheliak threaten to destroy the colony if it's not evacuated in four days (which is logistically impossible). Picard tries to negotiate with the Sheliak only to be rebuffed as they [[RulesLawyer cite various terms of the ridiculously complicated Treaty of Armens]]. Finally, Picard discovers a clause he can [[http://www.youtube.com/watch?v=ILbLGNDqUxA use against the Sheliak]]. He invokes the right to select a neutral third party to arbitrate, and chooses a race which is the middle of a six-month hibernation cycle. This time, it's the Sheliak's turn to balk (and finally, acquiesce).
-->'''Riker''': You ''enjoyed'' that.
-->'''Picard''': You're ''damn right''.
* In one episode of ''Series/TheWestWing'', the President inadvertently accepts a gift that becomes politically troublesome. When he tries to return it, the local ObstructiveBureaucrat won't allow him, because it now belongs to the American people. Charlie tries several tacks to get it back, but the bureaucrat always finds a rule to block him. Finally, Charlie digs up a lawyer who's committed the entire US code to memory, and finds a clause specifying that the President ''can't'' accept a gift that would embarrass the United States.
* In ''Series/Daredevil2015'', Grotto, a Nelson & Murdock client, is being targeted by The Punisher. When Nelson and Murdock (after much convincing) get him to agree to come forward to the police, the District Attorney Samantha Reyes intentionally uses him as bait to lure The Punisher out of hiding, leading to his death. After Frank Castle is caught, Matt, Foggy and Karen visit him at the hospital with the intent of possibly representing him. Reyes attempts to send them packing by stating it's illegal for lawyers to defend a murderer that killed one of their clients, only for Matt to counter that if she's going to file the conflict of interest, Reyes will have to admit that she's responsible for jeopardizing Grotto's witness protection.

[[folder:Professional Wrestling]]
* Some promotions use a rule where titles cannot change hands, or other wagers or stipulations cannot be done, if there is a win by disqualification. For example, in WWE, some title matches can have the losing champion retain their title because they lost by DQ, intentionally or not. A {{Face}} may luck into this scenario, while a {{Heel}} may actively exploit it.
* Wrestling/TheNewDay defended their Tag Team Champion status this way both as heels and as faces. The three-man team defended the generally two-person title under the "Freebird Rule", where any two members of the team could be challenged for the championship on any night. As heels, when the fight seemed to be a losing effort, the third member would interfere, force a loss by disqualification, and the team would keep the title. At least once, this was used as a storyline title defense as faces as well. At Summerslam 2016, member Wrestling/BigELangston had been ({{kayfabe}}) injured with a low blow by [[Wrestling/BulletClub The Club, Gallows and Anderson]], and had to be substituted with Jon Stewart (yes, ''that'' Creator/JonStewart). As the pair were about to do the same to Mr. Stewart, Big E [[BigDamnHeroes came to the rescue]], losing the match, but saving both Stewart's testicles and New Day's now one year long championship reign.
* WWE's Night of Champions is a pay-per-view event where every championship is put on the line. In one match, heel Wrestling/CMPunk realized after several attempts that he couldn't quite guarantee victory against face Wrestling/JeffHardy, so after his latest failure, he simply [[https://www.youtube.com/watch?v=uwYLD0KuTXs left the ring, grabbed the championship belt, and began to leave the arena]], forcing the ref to initiate a count-out leading to his loss by disqualification and thus retention of the title. [[spoiler: As the announcers made the audience aware of this rule fu, Jeff recovered and forced Punk back into the ring for a win.]]

[[folder:Tabletop Games]]
* ''ComicStrip/KnightsOfTheDinnerTable'' the gaming community of Muncie is made of this trope, but especially [[RulesLawyer Brian Vanhoose]] who never met a rule he couldn't exploit. For example, a frustrated [[GameMaster B.A.]] invoked [[GrapplingWithGrapplingRules obscure "overbearing" rules]] in his game (a target is automatically overbeared by an angry mob, consisting of at least ten people) over Brian's objections and delivered a HumiliationConga to his group. Brian responded by having each party member hire 10 beggars to act as a mob and started mercilessly overbearing monsters.
* In [[TabletopGame/LegendOfTheFiveRings Rokugan]], etiquette is one of the most important things to follow, sometimes resulting in a character getting his or her head cut off before the end of the night, without appeal, for saying something wrong or using inappropriate body language. The easiest way to get out of such a conundrum is to set it up so that reporting you would make more trouble for the person trying to make the report (for example: Ninjas officially do not exist. Trick someone into [[FalseDichotomy accusing you of being a ninja or not accusing you at all]], and they have no choice but to shut up or be executed while you get punished for a minor crime or even get off scot free). Members of certain clans get special exemptions for limited etiquette breaches, but if they RulesLawyer too much, an NPC or fellow player is liable to say that they clearly know the rules and should be punished for their breaches accordingly.
* There's [[http://www.diplom.org/~diparch/resources/humour/coast_moscow.htm a rather humorous story]] about a game of ''TabletopGames/{{Diplomacy}}'' where during a Winter phase (when each player can raise units) Russia ordered a fleet be raised in Moscow (a landlocked province where fleets can't enter at all) and then ''[[RefugeInAudacity tried to justify it as legal]]'' (normally such an order would be declared invalid and thus ignored) by referring to the rulebook. Turkey vehemently protested (in the context of the game, it was clear the move was hostile to him). Eventually, Italy and Turkey were able to use that same rulebook against Russia to have the order declared invalid.
* [[http://imgur.com/gallery/V0gND This story.]] ''TabletopGame/Warhammer40000'' {{Loophole Abuse}}r deploys his entire army in reserve. His opponent's response? Deploy a line of scouts along the enemy's table edge, leaving no legal space for his army to enter. Judges rule that the second player has won the game.
* Happens frequently in ''TabletopGames/DungeonsAndDragons'', occasionally between players but more commonly between the player(s) and the DM. As an example, early versions of the rules for truth-divining spells (I.E. spells that would tell if player was lying or not) [[FromACertainPointOfView did not account for half-truths]], [[ExactWords creative wording]], or lies that [[IBelieveThatYouBelieveIt the teller believed were true]]. Thus they could be circumvented by inventive players, like mages hypnotizing their willing partymates to forget incriminating details of their activities, or smooth talkers finding ways to omit details from their responses or answer in a way that's "technically" truthful ("Me? No, I didn't kill the prince, that lion that mysteriously got released into his bedroom did.")

* In Theatre/TheMerchantOfVenice, this is what is used against Shylock, the Jew moneylender who demands his pound of flesh from Antonio. Shylock pleads his case in court, and the court finds that indeed, the contract he made with Antonio is binding. This gives Shylock every legal right to extract a pound of flesh from him. However, Antonio is saved because it is ruled that Shylock cannot collect his pound of flesh without making a number of violations against Antonio's body. He asked for a pound of flesh, which means he can't take any more or less than an exact pound without violating his contract. The contract also did not include taking Antonio's blood which Shylock is therefore not entitled to, but cannot avoid spilling by taking the flesh. These two points along with the fact that his contract never included not being held accountable for potentially killing Antonio means that the court can use this LoopholeAbuse to bring down the full force of the law upon Shylock. To rub salt into the wound, he is forced to convert to Christianity by the man he tried to take vengeance on, and he cannot even take his own life to get out of it (note that by the standards of Shakespeare's time his forced conversion would be a just punishment and be considered salvation of the "villain"; Values Dissonance makes it come off as extremely cruel and religiously-intolerant).

[[folder:Web Comics]]
* Done once by Tristan from ''Webcomic/AngelMoxie'', when accused for wearing socks in breach of school's statutes on dress. She retorted that they were stockings and quoted a point that saying that if the student didn't want to wear the prescribed socks, she has to wear stockings; to the shock of the teacher, the statute didn't say anything about what those stockings should look like.
* In ''Webcomic/SkinHorse'', [[http://skin-horse.com/comic/will-be-provided/ when trying to save a client from a BlackOps base.]] ''[[http://skin-horse.com/comic/dismissed-from/ Twice.]]''
-->'''General:''' You're evil.\\
'''Tip:''' I know, but I ''try'' to use it for good.
* In Webcomic/FreeFall, Florence must obey direct orders from legitimate human authorities. It doesn't take her long to learn tricks. For example, [[http://freefall.purrsia.com/ff1600/fc01504.htm The mayor gave me a direct order to stay here, she never said I couldn't build a fusion test reactor on premisis]]. Later, she advises the mayor on rule-fu, pointing out that a temporary dictator could give uncancellable orders.

[[folder: Web Original]]
* ''Literature/WhateleyUniverse'' has Jadis' lawyer pull an epic one, made even more epic by going on for a good fifteen minutes, most of which is brushed over, but described as an epic battle, allowing the user to imagine it. Jadis got off.

[[folder:Real Life]]
* [[http://www.snopes.com/college/admin/cakesale.asp Urban legend:]] A modern student at Oxford or Cambridge points to a four-hundred year-old rule stating that the university must provide "cakes and ale" to him as he takes his exam. The university complies (with the modern equivalent, a burger and a Pepsi), and then promptly fines him for not wearing his sword to the examination.
** [[TruthInTelevision The fact that a legal rule hasn't been invoked for centuries doesn't mean it has been repealed.]] Case in point: [[http://en.wikipedia.org/wiki/Ashford_v_Thornton Ashford v. Thornton]]. In 1817, after Abraham Thornton was found not guilty of the rape and murder of Mary Ashford, Mary's brother William took the case back to court, where Thornton demanded a TrialByCombat. Since the laws for trial by combat had technically never been repealed, the jury granted the request. William Ashford, seeing the writing on the wall, decided not to go through with it, and Thornton walked free again. The laws concerning trial by combat were quickly repealed after the case was over, though, so nobody could try a similar stunt.
*** In this particular case, William was taking advantage of an archaic rule himself. Thornton had already been tried and had been acquitted by a jury, normally a bar to further prosecution. William was taking advantage of a by-then nearly obsolete rule which allowed a private individual to bring a criminal case. Trial by combat wasn't generally available to criminal defendants, but it was still listed as a defense in this sort of private prosecution. Thornton's attorneys advised him to invoke the trial by combat rule to point out how irregular the second prosecution was in the first place (and of course to win, since Thornton totally outmatched William). Parliament got rid of the trial by combat following this whole debacle, [[ObviousRulePatch but they eliminated the private appeal as well.]]
* This is how law in general works. There will generally be a good reason for a rule which nonetheless ends up being exploited for an unpredicted purpose by a RulesLawyer in court or applied incorrectly/not as expected/[[ExactWords exactly as written and no further]].
* This is why they had to get Al Capone on tax evasion; everything ''worse'' that he'd done, he'd managed to squeazle his way out of. [[JusticeByOtherLegalMeans The taxes were the only thing the authorities could actually make stick]].
** This also why [[http://en.wikipedia.org/wiki/Taxation_of_illegal_income_in_the_United_States tax forms in the US have a box to report "other income"]][[note]]Line 21 on a 1040 return. "Other income" also encompasses legal sources of income that isn't covered by any of the previous lines, like jury duty pay[[/note]]. If you've profited through any crime and don't report it, the government only has to prove that you have unaccounted-for income, so they can book you on tax evasion (and possibly filling out a falsified form) if nothing else. The presence of this box prevents any criminal from claiming that their illegal profits were unreported because they didn't fit any of the categories present.
*** However, income tax in general is more of a case of "[[ScrewTheRulesIMakeThem bringing a sawed-off shotgun to a Rule Fu fight]]": Fill it in and you've confessed to a crime (unless you write in "Fifth Amendment" or otherwise invoke it on that form in regards to the source - it's not the IRS's job to prosecute you for violations of criminal code not involving taxes[[note]]Legally, anyway - in practice those that do tend to get extra scrutiny by the FBI[[/note]]), [[MortonsFork don't and you're guilty of tax evasion (for failing to report the amount of income).]]
*** On the other hand, you ''can'' deduct the costs of anything related to your illegal income because you can treat it like a business expense, for instance the legal fees associated with your inevitable legal court battle with the government.
* One involving literally a SawedOffShotgun: gun laws of some countries prohibit hidden firearms (for obvious reasons) and use of buckshot on large game (for humane reasons), but have a very narrow definition on what a "hunting long gun" means. That is, a long gun has a barrel over 30cm (12in) in length and a total length of at least 60cm (24in). That means a modern pump-action or semiautomatic shotgun could be cut to the legal minimum total length and be [[OhCrap hidden but fully legal]], while buckshot could be bought under the guise of range shooting, both providing a perfect cover for poaching. The solution was typically [[ObstructiveBureaucrat Obstructive Bureaucratic]]: specify that a civilian long gun has the legal length '''and a stock''', and totally prohibit the sale of any buckshot round above size 4 (5-6mm per pellet).
* The "Public Interest defence" built into the UK's Official Secrets Act, which at least theoretically guarantees immunity from prosecution for anyone leaking classified information to the press ''if and only if'' it proves that government officials have been breaking the law, abusing their authority or both.
* [[https://notalwaysright.com/taxing-taxing-part-2/60491/ A student harangued by the tax board]] finally decides that if they're going to be taxed as a resident of California, then they need to receive the services their taxes pay for... like a refund on the $10,000 out-of-state college tuition they've had to pay as a non-resident.
--->'''Student:''' But you, the tax franchise board, are saying that I am a resident of California. Refund me my out-of-state tuition. You can take the eight bucks out of that.
--->'''Tax Board:''' *beat* I think we might be able to overlook this.

!Examples of 2:

[[folder:Comic Books]]
* One [[Creator/DarkHorseComics Dark Horse]] comic involved a Steampunk robot that killed people according to Bible quotations. To stop it, the protagonist countered every quote with one that was the complete opposite: "The lord is invincible"/"Chariots of iron";

* Partway through ''Literature/HarryPotterAndTheOrderOfThePhoenix'', one of the students points out that Umbridge is in violation of one of her own arbitrary rules. Subverted in that [[ScrewTheRulesIMakeThem all that happens is that the student gets a detention]].
* In ''Literature/LesMiserables'' during the arrest of Fantine, Jean Valjean, as Madeleine, must cite an obscure law giving him, as mayor, authority over the police, when Javert refuses to let Fantine go.

[[folder:Video Game]]
* In ''VideoGame/ShadowrunReturns: Hong Kong'' the scribblings of a madwoman mentions that [[spoiler:the Yama Kings]] are all liars and deceivers, but liars and deceivers who have to follow certain rules when making bargains. These rules, however, only apply if both parties are aware of said rules' existence, which means that the only person who could ever trust [[spoiler:a Yama King would be another Yama King]]. [[spoiler:Needless to say this piece of seemingly minor trivia is very useful when you eventually encounter one.]]

[[folder:Visual Novel]]
* This is how you take down the BigBad of ''VisualNovel/PhoenixWrightAceAttorneySpiritOfJustice''. [[spoiler:Ga'ran Sigatar Khura'in, being the queen of the Kingdom of Khura'in, can [[ScrewTheRulesIMakeThem create new laws whenever things don't go her way]]. The only way to bring her to justice is to prove she has no spiritual power, which is mandatory for queens in this kingdom, meaning she has no legitimate claim to the throne and all laws she has created are null and void.]]
* In ''VisualNovel/PhoenixWrightAceAttorney'', Phoenix engages in a spirited bout of Rule-Fu with the final case's villain, [[spoiler: Police Chief Damon Gant. First, Gant insists he has immunity from testifying by dint of his position as Police Chief, which Phoenix eventually baits him into waiving. Gant then tries to force Phoenix to implicate his own client by making him present a piece of cloth from the murder victim with her handprint on it; Phoenix instead insists he has no evidence to present. When Phoenix later presents the cloth as evidence of Gant's guilt, the police chief tries to have it declared inadmissible because Wright did not present it earlier when asked (which he was required to do by the laws of evidence); Phoenix counters that, when Gant asked, the piece of cloth had no significance to the case (as Gant had not yet admitted to cutting it from the victim's clothing) and, thus, he could not have presented it as part of the case. Cue an extremely satisfying VillainousBreakdown from Gant.]]

[[folder:Western Animation]]
* Done once in ''WesternAnimation/PigCity'': the SadistTeacher becomes the new Director; only to lose his job when students prove he doesn't know Latin, which is required to perform this function.
* An episode of ''WesternAnimation/{{Doug}}'' has Doug's ''entire class'' put into detention by [[DeanBitterman Vice-Principal Bone]]. This prompts a ''Quailman'' [[ShowWithinAShow fantasy sequence]] where Doug's superheroic alter ego faces down the Rulesmeister, master of arbitrary rules, and eventually defeats him by pointing out he's wearing mismatched socks, one of the many things he has a rule against. This carries over back into reality, when Mr. Bone snatches a comic book...and Doug points out that one of the rules is "No Snatching Other Peoples' Comics!"
* In the ''WesternAnimation/{{Futurama}}'' episode "How Hermes Requisitioned His Groove Back", Hermes defeats ObstructiveBureaucrat Morgan Proctor by uncovering an old "notification of romantic entanglement" form she had filed. The file wasn't used as proof of sexual impropriety, however: it was the fact that she had stamped it ''four'' times instead of the requisite five that got her demoted. However Hermes also got demoted for organizing the Central Bureaucracy ''too'' fast, since "a good bureaucrat never finishes early" and he still had 5 seconds left on his time limit. [[spoiler: Morgan's offence was considered bigger than Hermes's. She, who was a Grade 19 bureaucrat before this defeat, was forced to turn her bureaucrat badge in while Hermes was just demoted from Grade 36 to Grade 38. He was even promoted to Grade 37 for turning Morgan in]].
* In ''WesternAnimation/StormHawks'', the heroes get into a competition with the Rex Guardians, another Sky Knight squadron. In each game, the Storm Hawks do better than the Rex Guardians, but lose because the Hawks aren't following 'The Code', an ancient set of rules the Guardians follow rigorously. In Piper's contest, she wins by pointing out her opponent's uniform isn't ''exactly'' as it should be, and the judges are forced to concede.
-->'''Harrier:''' But...that was-!
-->'''Piper:''' A taste of your own medicine?

[[folder:Real Life]]
* Discussions on the merits of religion in general and Christianity in particular - which, as we all know, [[BlatantLies are always civil and polite]] - often involve a fair amount of [[Literature/TheBible biblical]] Rule Fu. Expect Bible quotes containing bizarre and/or ValuesDissonance-heavy rules to be tossed around liberally. More rarely, devout Christians arguing with ''other'' devout Christians may also play Rule Fu with the Bible.
** Actually the tradition of Rule Fu among Christians is long and storied which has led to the dozens of different denominations in existence today. This is at least partially a side-effect that the earliest Christians were converted Jews, and JewsLoveToArgue about ''precisely'' this sort of thing.
** Jesus didn't much care for the Rule Fu which is what He didn't like about the [[RulesLawyer Pharisees]]. And according to some denominations His very existence was about creating a loophole and also guiding His followers more towards the spirit of the rules.
** Expect any statement that "X must be accepted and done because it's stated in the Bible" to be followed up by quotes of many, many other examples from the same source that pretty much no one follows, and to modern eyes would lie somewhere between "comedically ridiculous" and "will land you on death row for doing". Comically illustrated in this [[http://www.queerty.com/this-flow-chart-that-destroys-religions-case-against-gay-marriage-is-so-easy-any-zealot-can-use-it-20150506 flowchart]].
* For those who follow UsefulNotes/AustralianPolitics this is Bronwyn Bishop's stock in trade, being a type one before becoming Speaker and the biggest fan of type two now.