History Main / LieDetector

* Subverted in ''TabletopGame/GURPSHighTech''. Even if the polygraph works as advertised (by default it doesn't) the machine still doesn't detect lies, the interrogator is the one doing that. By ''[[TabletopGame/GurpsUltraTech Ultra-Tech]]'', lie detectors that operate on micro-expressions and brainwaves have been perfected.

* ''Series/TheTwilightZone1959'': In "[[Recap/TheTwilightZone1959S3E24ToServeMan To Serve Man]]", the aliens' representative agrees to a polygraph test, after a few test questions suggest it works on him (i.e., "How did you come to this planet?" "I walked.") the alien claims that their intentions on Earth are solely to help humanity, and the polygraph reads it as truth.

-->'''Bob:''' Maybe it's out of gas, [[CanadaEh eh]]? ''[Doug farts]'' Uh, man! You farted!\\

** Another episode has a straighter example in the form of an alien [[VideoGame/HalfLife headcrab]] monster that has been trained by the local merchant guild to sit on people's heads and stab through their skulls if they tell a lie. It requires incredible force of will to fool, and Crichton would have been killed by it if not for the fact that [[spoiler:he has access to an identical twin for whom the statements he has to say are indeed true]]. The villain of the episode manages to deny all of his crimes with much effort, but can't successfully say a false answer to a big question that Crichton asks completely by accident: [[spoiler:"Well, aren't you just a good and loyal son?"]].

* Used in great comedic effect in ''Film/MeetTheParents''. Already intimidated by Jack Byrnes, Greg is hooked up to the machine. When Byrnes asks "Have you ever watched a pornographic video?", Greg visibly stumble through a "No" while the needles flicker about wildly. He later finds out that Byrnes is a LivingLieDetector, so the polygraph was just a prop.

* ''Animation/MotuPatlu'': Dr. Jhatka invents a lie-detecting robot in the episode "Lie Detector Robot". The robot, upon hearing anyone say a falsehood, gives them a big DopeSlap. However, John the Don and his minions try to steal it and accidentally damage it in the process, causing it to slap people [[ReversedPolarity if they say anything true instead]].

* ''Literature/TheStarBeast''. A "truth meter" is used on witnesses during a court trial. When the subject lies, a needle swings into the red zone, a ruby light flashes, and a warning buzzer goes off. As with the H. Beam Piper example, Heinlein notes the limitation that such a machine cannot actually detect sincere but mistaken beliefs. A witness is telling all sorts of lies and the device keeps going off (indicating that on at least some level she knows she's lying). At one time, however, she tells an obvious falsehood and the buzzer doesn't go off. The judge concludes that she really believes what she is saying...even though it patently is false.

While PerpSweating an especially naive criminal, the cops may employ a ''fake'' lie detector, often a photocopier with an ominous paint job. The device really ''is'' a photocopier, secretly loaded with pages that have been preprinted with the words "TRUE" and "FALSE". The cops use the machine's answers (sometimes along with a warning that this is a new and experimental model of lie detector that could cause cancer or erectile dysfunction) to coerce the perp into a confession. (Note: some people claim this has happened in real life, but ''{{WebSite/Snopes}}'' has [[http://www.snopes.com/legal/colander.asp its doubts.]])

A real life polygraph test typically works by asking you a mixture of embarrassing "control" questions in which everybody is expected to lie (for example "Have you ever lied to a loved one"), and relevant questions ("Did you do it"). If your physiological response on the relevant questions is the same or higher as on the control questions, you are deemed to be lying. Ironically, this means that being perfectly honest makes you more likely to fail the test.

In real life, there is little to no evidence that polygraphs perform better than chance. Interpretation of the results is highly subjective and usually biased by prior suspicions. And even if polygraphs did work, it is trivial to beat them using measures such as biting ones tongue or thinking exciting thoughts to increase responses on the control questions. Most polygraph operators know this; the polygraph is a distraction, and it's the operator who's really watching you.

Interesting note: The polygraph was invented by William Moulton Marston, who also created the character of Franchise/WonderWoman... who happens to wield a magic lasso that ''forces'' people to tell her the truth!

* A commercial for Snapple in the '90s had the writer of a fan letter (in which he states his love of Snapple and says [[SuspiciouslySpecificDenial "I am not lying when I say this"]]) brought in for a polygraph test to prove he really was being honest. The machine is realistically depicted as graphing his stress levels with wiggling pens. He passes.
* A [[https://www.youtube.com/watch?v=d7A1dbsvdtw Cars.com advert]] had a couple talking about the lack of drama in buying their car from a Cars.com sponsored dealership. So to make up for it, the dealership hooks up the husband to a polygraph, and tell the wife to ask her husband anything. She then asks if [[DoesThisMakeMeLookFat he thinks her sister is prettier than she is]], whereupon the husband starts [[TakeAThirdOption laughing and then rips off the polygraph sensors to avoid answering the question]].
* An advert for antiperspirant had a FemmeFataleSpy being tested, but she passed the 'galvanic skin response' thanks to the product.

* ''Literature/KonoSuba'': After Kazuma is accused of deliberately teleporting a bomb to the governor's house, he is arrested and interrogated via a magic item capable of detecting any lies told in the vicinity. After being forced to honestly answer a few questions that make him uncomfortable, Kazuma manages to convince the interrogator that he was genuinely trying to save the city of Axel; however, he accidentally sets off the lie detector by claiming to not be acquainted with any of the Demon King's generals, having forgotten that Wiz is still technically one of them; as a result, he is misunderstood as being in league with the Demon King's army and put on trial. During the trial proper, Kazuma's culpability is aggravated due to circumstantial testimonies from various people that are taken entirely out of context; when all seems lost and the judge is on the verge of pronouncing him guilty, Kazuma loses his patience and loudly asserts that he is ''not'' in league with the Demon King or his army and that he is ''not'' a terrorist, which does not set off the lie detector and therefore is taken as truth. Unfortunately for Kazuma, the [[AristocratsAreEvil corrupt governor]] doesn't give a shit about his allegiance and threatens the judge into declaring him guilty anyway, [[ItsAllAboutMe since Kazuma did get his mansion blown up]].
* ''Literature/TheRisingOfTheShieldHero'' has an unconventional way to compel the truth through [[NotTheIntendedUse creative application]] of a Slave Crest. Slave Crests function as a MagicallyBindingContract between master and slave. When applied to someone, they become physically incapable of disobeying their master's orders. If they try to disobey the order anyway, the crest gives the slave a magical electric shock [[{{Geas}} until they do whatever it was that they were told to do]]. During a court trial, a Slave Crest can be applied to a witness with the judge as their master, who then orders the witness to "tell the truth". This would make the Slave Crest shock the witness if they lied in court. [[spoiler:This application of a Slave Crest is how Malty's FalseRapeAccusation against Naofumi gets dismissed; Malty is such a CompulsiveLiar that she can't help but lie in court, even after being told what the Crest would do and being shocked repeatedly from lying to the judge. Malty is eventually asked point-blank if Naofumi attempted to rape her; when Malty says that he did, she's zapped by the Slave Crest with such intensity that she's knocked flat on her back. Since it's clear that Malty is lying, the charges against Naofumi are dropped.]]

* Franchise/{{Superman}} once encountered an inquisitive college professor who began to suspect that one of his students was Superboy and started asking everyone if they were him as a demonstration for the workings of a lie detector. Superman avoided detection by realizing he was no longer a "boy".
* The 1980's British ''Starblazer'' comic had the Truth Meter and the Truth Sensors, but the latter took a long time to work.
* Subverted in ''ComicBook/{{Camelot 3000}}'', when King Arthur has each of those suspected of betraying Merlin hold Excalibur while swearing their innocence, saying that the sword can cleave truth from falsehood. The prospect of having to do this makes the culprit break down and confess, after which Arthur admits that he'd made up the claim that his sword can do any such thing.
* ''ComicBook/TheIncredibleHulk'': In one story, General Ross tried to get Doc Sampson to take a lie detector test regarding his knowledge of the Hulk's whereabouts, forgetting that as a psychologist, Sampson would be perfectly capable of deceiving it. Sampson's response was to threaten to [[AssShove cram it into one of Ross's orifices]].
* ''ComicBook/WonderWoman1942'': ComicBook/SteveTrevor tried to hook Paula von Gunther into a lie detector before questioning her in the first issue, but she managed to hit him with it so she was taken back to her cell instead. This story has the bonus of being written by one of the inventors of the lie detector, William Moulton Marston.

* ''ComicStrip/DickTracy'' had a classic scene where an actual lie detector was used for a great trick in The Blank story. Tracy has a criminal in custody who apparently knows who The Blank is, but he will not cooperate. So, Tracy convinces him to take an optional lie detector test and then asks him to look over some mug shots to indicate which one is The Blank. Sure enough, the criminal demands to be disconnected from the lie detector, only to be told by Tracy that by doing that he just revealed that the real identity of The Blank has a criminal record, a vital clue to work with.

* ''Fanfic/DungeonKeeperAmi'': Ami tried to used her Mercury Computer as one, in [[https://forums.sufficientvelocity.com/threads/dungeon-keeper-ami-sailor-moon-dungeon-keeper.31639/page-136#post-8635931 "Adamantine"]]:

* Used in great comedic effect in ''Film/MeetTheParents''. Already intimidated by Jack Byrnes, Creator/BenStiller was hooked up to the machine. When Byrnes asked, "Have you ever watched a pornographic video?" Stiller visibly stumbled through a "No" while the needles flickered about wildly. He later finds out that Byrnes is a LivingLieDetector, so the polygraph was just a prop.
* The Voigt-Kampf test in ''Film/BladeRunner'' -- although that is more of an emotion detector.
* ''Film/FlashGordon1980'': While Princess Aura is being interrogated by Klytus, she is hooked up to one of these. When she lies a light blinks and a siren goes off.
* ''Film/TheAdventuresOfBuckarooBanzaiAcrossThe8thDimension'': Lord Whorfin hooks Buckaroo up to the Shock Tower, which not only detects when Buckaroo is lying but gives him a shock when he does.
* ''Film/TheSentinel2006'': Basically the first plot twist. Secret Service Agent Pete Garrison is blamed for treachery and has to go on the run because he failed a polygraph test. Why? Because he was scared they'd find out he's been having an affair with the first lady!
* In ''Film/AnatomyOfAMurder'', the defendant's wife has taken a lie detector test, but its results are not admissible in court. Biegler mentions the fact anyway.
* The movie ''Film/{{Sneakers}}'' plays this oh-so-straight. The sneakers improvise a lie detector out of an old Cradle Modem and some miscellaneous equipment. They attempt to hand-wave it by saying that it's not as good as a real lie detector because it can only test the stress in the person's voice(Note, that this is through a phone line, and into a device that essentially puts a microphone up to the earpiece), but it still seems to work perfectly and they trust the results implicitly.
* In one of the ''Film/OceansEleven'' films, the team nerd has to pass a polygraph test as part of a scam, and spoofs the system by keeping a thumbtack in his shoe and pressing his foot down on it while answering the calibration questions. Later in the same movie, the sophisticated computer systems can tell if a person was cheating at the games by reading various body signals. It is fooled when the rigged slot machine gives off the giant jackpot to a random woman who didn't know about the con. The first example even has the person administering the test point out that, if he didn't have the machine, he would've sworn that Livingston was lying. But the machine passes him.
* ''Film/BasicInstinct'': During Catherine's interrogation at the station, she offers to take a polygraph test, which seems to confirm that she's innocent. Nick counters that she simply manipulated the results, because he knows people who have done it before -- not mentioning that he's talking about himself.
* In ''Film/{{Freejack}}'', Music/MickJagger's character Vacendak suspects a traitor in his team and wants to run everyone through a lie detector. When his NumberTwo (a longtime friend) starts to walk away, Vacendak tells him to "step up!" The other man puts his hand on the scanner and angrily recites his name, position, and his attitude towards being thought of as a traitor. Vacendak counters that he wasn't testing his friend, he was testing the machine. When the machine gives out the "truth" result, he adds that the machine works.

'''Ted:''' He's definitely lying all right.

* The humorous scifi novel ''Literature/WhoGoesHere'' by Bob Shaw had a natural extension of this trope: a MadScientist, frustrated with the failings of lie detectors, designed a device to force the subject to tell the truth. It consisted of deodorant to stop him sweating, and devices to keep the subject's breathing and heart rates constant. It failed.
* Appears in Creator/DavidWeber's ''[[Literature/{{Safehold}} Off Armageddon Reef]]'' as a piece of high-tech gear that looks like a glowing gem the protagonist recognizes but the locals regard as magical, with the color changing to indicate a lie. The protagonist very carefully phrases the answers to not set it off.
* In ''[[Literature/LandOfOz The Marvellous Land of Oz]]'', Glenda the Good possesses a magical white pearl that turns black in the presence of falsehood, which she uses to extract a confession from the witch Mombi.
* In the Creator/StephenKing novel ''Literature/TheWasteLands'', Roland and company are on board a high speed train run by a sophisticated A.I. The A.I. informs them it can tell with great accuracy when they are lying by monitoring voice stress patterns.
* The same thing happens in ''Literature/TheWarAgainstTheChtorr''. During a therapy session Jim [=McCarthy=] is told he's lying; he immediately jumps out of the chair he's sitting in. The therapist answers the unspoken question that yes, there are polygraph sensors in the chair, but he can tell Jim is lying from the stress in his voice.

---> "This is a veridicator. That globe'll light blue; the moment you try to lie to us, it'll turn red. And the moment it turns red, I'm going to hammer your teeth down your throat with the butt of this pistol."
* Creator/RobertAHeinlein:
** ''Literature/TheStarBeast''. A "truth meter" is used on witnesses during a court trial. When the subject lies, a needle swings into the red zone, a ruby light flashes, and a warning buzzer goes off. As with the H. Beam Piper example, Heinlein notes the limitation that such a machine cannot actually detect sincere but mistaken beliefs. A witness is telling all sorts of lies and the device keeps going off (indicating that on at least some level she knows she's lying). At one time, however, she tells an obvious falsehood and the buzzer doesn't go off. The judge concludes that she really believes what she is saying...even though it patently is false.
** In ''Literature/BetweenPlanets'', the protagonist Don Harvey is subject to questioning by Venus Republic soldiers while hooked up to a lie detector after first waiving his rights about self-incrimination.
* In Creator/RandallGarrett's story "Literature/TheBestPolicy," an alien race planning an invasion kidnaps a random human and hooks him up to one of these in order to get information. He manages to [[ExactWords cleverly word his answers]] so as to give them the impression that humanity is insanely powerful and not to be messed with.
* Creator/PiersAnthony's books:
** In ''Literature/OnAPaleHorse'', Luna and Zane hold Truthstones (which glow when someone lies) while discussing sensitive personal matters.
** ''Literature/{{Steppe}}'' gives us swords whose edges glow one color if a person is telling the truth and another if the person is lying.
* Creator/KurtVonnegut's novel ''Creator/PlayerPiano'' includes a courtroom scene where the protagonist is hooked up to a lie detector with a large dial ranging from "False" to "True".
* ''Literature/TheGoblinWood'' by Hilari Bell features an explicitly magical version of this; a bell that rings when a lie is told near it. This has its downsides, as indicated when its user is asked, "Are you sure this will work?" "Of course I'm sure--" Ding. [[spoiler:Later, her captive turns the questions around on her, and in response to her MotiveRant asks whether her ActualPacifist mother would appreciate the violent vengeance that has been taken for her murder. "If my mother was still alive, she'd be proud of me!" [[HeroicBSOD Ding]].]]

* The ''Literature/HeraldsOfValdemar'' series has the Truth Spell, the only form of magic known to the Heralds between the death of Vanyel and Elspeth's becoming a Herald-Mage centuries later. The spell has two forms: The weaker form is a truth/lie indicator, the stronger form forces the target to tell the truth as they know it.

* ''Literature/ForestKingdom'': In the ''Hawk & Fisher'' spinoff series' book 1, the suspects are questioned under a [[TruthSerum truth spell]], which forces people to speak only truthful statements. This attempt to find out who committed two murders fails, due to [[spoiler:the murders having been committed by two different people, each of whom could truthfully deny having killed ''both'' victims.]]
* In ''Literature/SnowCrash'' by Creator/NealStephenson the rump of the federal government (which pretends to still rule the [[DividedStatesOfAmerica USA]]) has its employees take weekly lie detector tests that may involve sedative drugs and NMR machines to detect activity in parts of the brain used for lying. It's a plausible technology for a reliable lie detector. Being that Stevenson is known for doing lots of research and [[ShownTheirWork Showing Their Work]], the book naturally includes rarely documented steps like collecting urine samples to check for drugs that might throw off the machine, and being taken to the test in an elevator so that you can't claim your heart rate is up because you just climbed the stairs.
* In William Brittain's story "Literature/TheArtificialLiar", one of the guards at a government research center was {{gaslighting}} a file clerk who lived in the same boardinghouse as him so that, during the inevitable investigation after said guard had smuggled out some highly sensitive material, his chosen patsy would have extreme reactions to the polygraph questions.
* The Katharine Kerr novel ''Literature/{{Snare}}'' has shamans who can smell whether or not a person is telling the truth. It works by detecting a person's emotional state through subtle changes in a person's scent (One of the talents held by the shamans is exceptionally sharp senses), and lying makes most people nervous. It's mentioned that this might not work against a habitual liar who would remain perfectly calm when deceiving others.
* Literature/TheStainlessSteelRat
** In the first novel Slippery Jim [=diGriz=] [[TrespassingToTalk breaks into the home]] of a politician and [[CorruptPolitician finds evidence of numerous corrupt deals]]. When confronted the politician denies everything, whereupon Jim reveals that the security robot holding him captive is also a lie detector. The robot confirms that 74% of everything the politician has just said is a lie...''except'' about the case the Rat is investigating. Their conversation then proceeds on a more amiable basis.

* {{Parodied|Trope}} in ''Literature/DiaryOfAWimpyKidCabinFever'' when the school is vandalized. The police come there to question the worst troublemakers, but it's obvious that their "foolproof lie detector" is just a photocopier. Whenever the troublemaker says something they don't like, they hit a button to copy a sheet that says "He's lying". Predictably, they fail to catch the real culprits.
* Subverted as early as 1913, in the ''Literature/FatherBrown'' story "The Mistake of the Machine". Father Brown is introduced to a Psychometric Machine that measures the suspect's pulse, and is rather scathing of the idea, saying American scientists must be great sentimentalists to try and prove things from heart-throbs. He proves his point when a man is accused of murder based on his pulse rate when the victim's name is mentioned, and Father Brown is able to demonstrate another reason for this.
-->'''Greywood Usher''': Now, in my opinion, that machine can't lie.\\
'''Father Brown''': No machine can lie. Nor can it tell the truth.
* In ''Literature/TheLostFleet'', interrogation rooms are actually brain scanners similar to an fMRI. The machine shows the interrogator when regions of the subject's brain associated with deception or various other emotions light up, so not only do they know when the subject lies, but they can also tell when [[ArmorPiercingQuestion one of their questions has really hit home]], even if the subject is refusing to answer at all. There are ways to deceive without setting off the machine, but those usually involve WeaselWords that a skilled interrogator can spot. Of course, the machine can still only tell you what the subject believes, so false answers with no deception noted are still possible from a dupe or a delusional subject.
* In the novelisation of ''Radio/{{Earthsearch}}'', the Chief Prosecutor of the Solaric Empire interrogates Astra with two cerebral analysers focused on her brain. Lying modulates the beams causing a feedback "that you are unlikely to survive." So when Astra says that the spaceship she's from is unarmed and stranded in orbit around another planet, the Prosecutor thinks it's safe to kill the prisoners. Astra isn't lying; she just doesn't know that the asteroid DeflectorShields make a handy ImprovisedWeapon and the surgical androids can be reprogrammed to pilot the spaceship, which arrives JustInTime for a BigDamnHeroes.
* Creator/IsaacAsimov and Creator/JanetAsimov's ''Literature/NorbyTheMixedUpRobot'': The truth wand used by Ing's minions will hurt you if you tell a lie. A mild shock for a small lie, and bigger shocks for bigger lies. Fargo demonstrates its effectiveness by saying [[TheCharmer he isn't interested in women]], then scolds his brother for suggesting such an outrageous lie.
* ''Literature/GoblinsInTheCastle'': Magical variant in ''Goblins on the Prowl'' -- Solomon's Collar, on top of letting the wearer [[SpeaksFluentAnimal understand and be understood by animals]], tightens and starts to choke them whenever they lie.

* In the short-lived ''Series/BionicWoman'', the Berkut headshrink is impressed by Jonas Bledsoe's ability to beat a lie detector while saying "I love you." Jonas puts this down to his long marriage.

-->'''Mr. Wick:''' "Carey, you're one of our most valued employees." [buzz] "Well, maybe not, but I respect you a lot." [buzz] "You've got a bright future here..." [buzz] "Oh, will you get these things off me! I don't like being tied down like this!" [buzz]
* ''Series/DoctorWho''
** In [[Recap/DoctorWhoS10E3FrontierInSpace "Frontier in Space"]] the Doctor is subjected to a MindProbe which is basically used as this trope. Unfortunately his interrogator [[TimeTravelersAreSpies refuses to believe he's telling the truth]] and keeps asking the same questions [[LogicBomb until the probe blows up]] (which the Doctor predicted would happen earlier).
** In [[Recap/DoctorWhoS39E4FluxChapterFourVillageOfTheAngels "Village of the Angels"]], Professor Jericho has Claire Brown wired up to a lie detector for a test of her psychic abilities, and gets annoyed when his baseline question about her date of birth registers as a lie. Unknown to him, she's a time traveler.

* An episode of ''Series/{{Nikita}}'' has [[spoiler:Alex]] hooked up to a "FMRI" [[spoiler:it looks alot more like an ECG]] and is able to trick it through short and precise statements that are technically true. The problem is that to make such statements avoiding a lie would cause a lot more activity in the brain than such short statements would produce normally.

** Also, the comedic take was subverted in an early season 10 episode with an ordinary lie detector, where the tester is tortured:

'''Vala:''' Thanks, you look excellent yourself... ''[needle ticks rapidly]'' I mean, very nice... ''[needle ticks rapidly]'' That is, not objectionable... ''[needle ticks rapidly]''...
* ''Series/GilligansIsland'': In "[[Recap/GilligansIslandS3E19LoveysSecretAdmirer Lovey's Secret Admirer]]", the Professor builds a lie detector out of -- what else? -- [[BambooTechnology bamboo and coconuts]] and tests all the men to find out who sent Mrs. Howell a love letter. One of the gags is The Skipper passing until he says, "See? I always tell the truth," which sets it off. [[BrickJoke At the end of the episode]], Gilligan is playing with it when Mary Ann comes in asking him what happened to a couple of coconut cream pies she made, and Gilligan denies seeing or taking them, [[ExplosiveInstrumentation which causes the lie detector to explode]].
-->'''Gilligan''': Well, they ''were'' delicious.
* Avoided in ''Series/{{Alias}}'', which features a more realistic lie detector--that is to say one that doesn't explicitly say "Truth" or "Lie", but just provides raw data such as heart rate and blood flow in particular areas of the brain, requiring the interrogator to use his own judgment to decide on the truth of a given statement, and being much harder to fool. Then, outright subverted, when the difficulty of tricking the device almost gives away the protagonist, when after extensive training and practice with her handler her results look ''too'' perfectly honest during the real interrogation.
* In the ''Series/JonathanCreek'' episode "The Tailor's Dummy", TV presenter Carla, who is preparing to host a talk show with a lie detector as the gimmick, uses it to prove to Jonathan she's happy in her marriage with the show's director. It announces she's lying. Later the director (who doesn't know about this) admits to Jonathan that it's completely random.

* In ''Series/{{Seinfeld}}'', Jerry takes a surprisingly realistic lie detector test to try and prove he doesn't watch ''Series/MelrosePlace''. Instead of being asked directly, he's just asked to give his details before being asked a string of questions about events from ''Melrose Place'' ("Did Kimberley steal Jo's baby?" "Did Billy sleep with Allison's best friend?" etc etc). And instead of lights or buzzers or wildly jagged needles, the needles just jiggle a little when he answers, but not in any significant way. In the end he breaks down under the pressure of endless ''Melrose Place'' trivia and confesses, and we never find out whether he was beating the machine or not.
* In ''Series/BarneyMiller'' episode "[[Recap/BarneyMillerS5E13 Voice Analyzer]]", the entire 12th Precinct is tested with a lie detector(a procedure that was the Hot Topic of the Day in the 1970s) after a newspaper report of corruption. Det. Wojciehowicz failed miserably due to being nervous and deliberately provoked, while Det. Dietrich passed perfectly (despite claiming to be from outer space) simply by remaining calm.
* In ''Series/StarTrekTheOriginalSeries'', the ''Enterprise'''s computer has a lie detector function seen in a few episodes.
** In "Mudd's Women", it states that Mudd's responses are "INCORRECT" when he gives a false name, claims he has no criminal record, and states that he is licensed to operate a spaceship. It's possible that the computer identified Mudd's face and then compared his statements to records, as it immediately provides the true answers.
** In the episode "Wolf In the Fold", it gives the response ''SUBJECT IS RELAYING ACCURATE ACCOUNT'' when questioning serial killer suspects.
* ''Series/StarTrekVoyager''. In "[[Recap/StarTrekVoyagerS1E7ExPostFacto Ex Post Facto]]", Tuvok uses an Autonomic Response Analysis to interrogate Tom Paris. It shows that he's telling the truth about not committing the murder he's accused of, which turns out to be a FrameUp. However in "[[Recap/StarTrekVoyagerS2E26S3E1Basics Basics, Part One]]", Chakotay requests the Doctor do an ARA to see if an alien prisoner is lying. The Doctor points out that they don't have enough baseline information on that species to give an accurate result.
* The sheriffs on ''Series/{{Reno 911}}'' frequently spend their downtime interrogating each other with the polygraph. Of course, the questions or responses invariably turn uncomfortably personal, and HilarityEnsues.
* ''Series/MrShow'': In [[https://www.youtube.com/watch?v=VdIDwYW_JZg this sketch,]] prospective employers are interviewing a job applicant and strap him to a lie detector that buzzes when it senses a lie. The interview starts with basic questions (like "Have you ever drank alcohol to excess?" "Have you ever stolen from an employer?" and "Have you ever taken an illegal drug?"), but they're soon flummoxed when the applicant - who answers everything in the affirmative - begins confessing to the most ludicrous things, including being addicted to every hard drug in existence, stealing pens and "space plans" from NASA, killing a man with his mind, skinny dipping with Michelle Goodwin, seducing a rich guy by posing as an affluent lady (which was made into a hit Broadway musical), [[SuspiciouslySpecificDenial and eating a train piece by piece after first derailing it with his penis]] (for charity). All the while, the lie detector is silent, indicating that he is telling nothing but the truth. [[spoiler: Eventually, the employers - who are revealed to be the operators of a shoe store - give him a job, and the applicant says that [[BlatantLies he loves shoes]]. BUZZZT!]]
* In the short-lived sitcom ''Quintuplets,'' two of the brothers, Pearce and Parker, try to make a lie detector in order to find out which of the two their mutual crush likes better. Unlike most detectors, when someone lies, the detector makes toast. Pearce is the one to put the thing together, and tests it out on himself. He sets it up, and tells Parker to touch it. The detector gives Parker a (very painful) shock. Pearce tells Parker, "I had no idea that was going to happen." Toast pops out, leading Pearce to gleefully exclaim "It works!" [[HilarityEnsues Hilarity (and disaster) ensues.]]
* There's one beneath the Buy More in ''Series/{{Chuck}}'', which they use to question a character about Fulcrum activities. Too bad Chuck didn't pay attention to the last answer...
* ''Series/LieToMe'':
** The show, which bases its detection off people's [[YouCanAlwaysTellALiar microexpressions]], hates polygraphs. The characters point out that your reaction is going to be altered if say, a hot chick walks in and takes over the lie detector exam. Also that you might as well use a large egg being held in your hands as one, because if you are under stress and squeeze and break it, that could indicate that you're lying. In one episode, they show it's possible to beat a polygraph by taking a depressant to decrease your body's stress reaction. The main character can make utter hash out of not just polygraphs, but ''his own system'' - in the pilot episode, he tests a recruit by ''faking'' stress.
** In a later episode, they use a (fake) polygraph on a suspect who he knows is going to try to trick the system. The idea is that he'll focus on trying to trick the polygraph instead of the people reading his facial cues.
* Used twice by ''Series/HomicideLifeOnTheStreet''.
--> "We're gonna ''neutron'' this son-of-a-bitch!"
** Parodied in at least one case; the 'lie detector' turns out to be a photocopier that the detectives have loaded with sheets of paper with "LIE!" printed on them, which they use to trick particularly credulous suspects into confessing the truth.
** The fifth season premiere of ''Series/TheWire'' opens with Bunk Moreland and a bunch of other detectives also using the photocopier trick to trip up a suspect after convincing him that his accomplice has flipped on him by having said accomplice led past the interrogation room with [=McDonald's=] food they purchased just for him. No surprise to consider both shows were created by David Simon based on his experiences shadowing real Baltimore police officers.
* ''Series/NinjaTurtlesTheNextMutation'': In "Truce or Consequences" Donatello invents a lie detector. He used it to see if Wick was serious about defecting. However, Wick was also gushing about Michaelanglo's radio show at the same time he said he wanted to defect, so the lie detector read his statement as true, causing the Turtles to walk into a trap.
* Repeatedly on all versions of ''Series/LawAndOrder''.
** The show frequently alludes to its fallibility and inadmissibility in court, at least.
* As always, ''Series/MacGyver1985'' did it. As always, it worked well enough to cause the villain of the week to give himself away. Notable components included an alarm clock and a sphygmomanometer.
* Used in ''Series/TheUnusuals'' against a serial killer of cats. It appeared to be a Lexmark or Canon inkjet printer with the lid over the scan plate removed.
* ''Series/RoboCopTheSeries'':
** Robocop was literally a walking lie detector. He used "voice stress analysis" to make instant, near-infallible truth assessments. However, it was very plot-sensitive; Robo could easily use it to interrogate low-level criminals and witnesses, but the ''real'' bad guys always had ''some'' way to beat it.
** A recurring nemesis was able to make the system give null responses because he was a stone-cold sociopath.
** Once they had to interrogate a career politician, which just plain ''broke'' the system. He was such an instinctive liar that every statement he made registered exactly halfway between truth and falsehood. He was able to make the system give a null response to a claim that he was ''Abraham Lincoln.'' He walks out because a female acquaintance (not his wife) explains that they were together at the time of the crime. The machine works this time.
* In the ''Series/{{Torchwood}}'' episode "Adam", Jack uses the "best lie detector on the planet" (complete with green/red light) on Ianto, who has had false memories implanted. Since Ianto is convinced he's murdered 3 girls, no lie is detected ... but Jack still knows he's innocent.
* ''Series/TheCommish''. The title character knows that an informant is somehow beating the lie detector, and uses a HoneyTrap to find out how. It turns out he's placed a thumbtack in his shoe, and is pressing down on it so as to give the same response each time. The Commish schedules another test, then has him walk up and down an endless amount of stairs under the excuse that the testing area keeps getting changed. Eventually the informant realises the game is up and removes the tack to give his by-now extremely sore foot a rest.
* ''Series/{{Battlestar Galactica|2003}}''. In a flashback to before the war, Adama is seen applying for a job in which he must take a lie detector test. One of the baseline questions (used to establish the reliability of the other questions) is "Are you a Cylon?" (This was before anyone knew the human-looking Cylons existed). Adama walks out of the test after getting angry about having his word questioned.
* ''Series/TheParkers'': A lie detector watch zaps when the wearer tells a lie.
* ''Series/SeaQuestDSV'' has a police officer in one episode with a sneaky lie detector. He hands people a roughly pen shaped object, tells them it was found at the scene and asks if they have any idea what it could be. After they answer in the negative he proceeds to ask regular questions. The device is actually a lie detector which he owns and he is tricking them into holding it while being questioned.
* The first episode of ''Series/LoisAndClark'' has a polygraph that works this way. Clark's 'baseline' questions are 'Is your name Clark Kent' and 'Are you Superman'; he's supposed to say yes to both and get a 'lie' response on the second, and even though he's totally freaked out at saying it to the Superman-hunters, saying 'yes' he's Superman gets a no-lie flatline. The hunters mutter "the machine is broken or this reporter is so mild-mannered he hasn't got a pulse," to make things more confusing, and funny. He sets it off by ''blowing'' on the needle with super-breath to get his no, then sets it off by saying he can't contact Superman. (Although it's fine with 'I've never met Superman.') Magic! On another question where he needs to set it off, he levitates an inch above the floor and drop the chair, setting off the needles.
* [[https://www.youtube.com/watch?v=xKgmScYcK6g This]] old Johnny Carson skit on ''Series/TheTonightShow'' involves a politician who agrees to be hooked up to one of these at a press conference, with the expected hilarity ensuing.
-->"I feel my opponent is a decent man." [BUZZ!] "He's an okay man." [BUZZ!] "He's a man." [BUZZ!] "He's bisexual."
* An episode of ''Series/TekWar'' had a hardline investigation unit use a combination lie detector/shock collar - {{Hand Wave}}d as a neural interface which detects "[[TechnoBabble cognitive dissonance]]" instead of just reading biorythyms, and turns said dissonance into ''[[AgonyBeam direct stimulation of the pain center]].'' It's used once on a known criminal, who gives truthful information after realizing his training(TruthInTelevision) can't beat the device. However, the designers never accounted for someone absolutely determined to defy the device; it's later used on a hotel maid that they suspected was concealing evidence. TheMobBossIsScarier, she hated the cops, so she denied knowledge despite increasing levels of pain until it rendered her comatose.
* In ''Series/PanAm'' Kate has to pass a lie detector test [[spoiler: that she has to lie to in order to not incriminate herself regarding a man she shot]].
* In ''Series/{{Psych}}'', Lassiter uses one on Shawn with excuse that he's just testing whether the machine is working or not to figure out whether Shawn's secretly dating Juliet. The machine appears at first to be a typical hyper-accurate bit of HollywoodScience (registering an honest response when Shawn blurts out that he's in love with Juliet while hooked up to it), but promptly subverted when Lassiter follows up with the question [[WhamLine "are you psychic?"]]. Shawn lies and still passes the test. A flashback at the end of the episode reveals that learning how to beat a lie detector was one of the many skills Henry taught Shawn as a young boy (namely, trying to believe in the lie so that the polygraph registers an honest response).
** At the end of the episode, Lassiter invites Shawn into the interrogation room and hooks himself up to the machine. He then proceeds to tell Shawn that if he ever hurts Juliet in any way, he will discharge his pistol. Repeatedly. The result? Zero deception.
* On ''Series/{{Roseanne}}'', the employees of Rodbell's have to take a lie detector test. During the end credits, manager Leon is asked about Roseanne and the machine explodes when he lies and says he thinks she's a good worker.
--> '''Polygraph Tester''': Do you consider Roseanne a good worker?\\
'''Leon''': Well... I... I guess... she has her--\\
'''Polygraph Tester''': Yes, or no, Mr. Carp.\\
'''Leon''': Well... okay then... (nervous pause) Yes. (The Polygraph explodes, sending sparks everywhere) ...I knew that was going to happen.
* ''Series/HotSeat'' was a short-lived ABC game show from 1976 (premiering the same day ''Series/FamilyFeud'' did except it aired at the low-clearance 12 noon spot) that had couples being asked questions about their married life while attached to a device that measures emotional levels.
* Talk shows like ''Series/{{Maury}}'' and ''[[Series/TheJerrySpringerShow Jerry Springer]]'' use this all the time, often to find out whether a spouse or significant other is unfaithful or for other purposes. So much so that the use on Maury has now become a meme!
-->"You said that [Statement]. [Contradiction] determined that was a lie".
* Also used in Great Britain by Jeremy Kyle on his lowest-common-denominator [[Series/TheJeremyKyleShow confrontation show]] and treated as if it had God-like infallibility. This led to the show's downfall when a guest in an upcoming episode was DrivenToSuicide after a test determined he was cheating on his girlfriend.
* In the ''Series/{{Smallville}}'' episode "Committed", a psycho named Macy would kidnap couples and hook them up to these, then question them about their love lives and fidelity. For each lie, the other person gets electrocuted. When Macy mistakes Lois and Clark for a couple and kidnaps them (thanks to kryptonite), Lois answers "Yes" when she's asked if she loves Clark, which registers as the truth much to Clark's shock as the pair couldn't stand each other at this time. Later, after they are freed, Lois [[BlatantLies claims that she slipped the sensor off her when she gave her answer]].
* In the ''Series/MurdochMysteries'' episodes "Still Waters" and "Invention Convention", Murdoch has a device of his own invention called a pneumograph, which as the name suggests, measures the suspect's breathing. Instead of the lights, his machine has blue liquid that rises in a spiral-shaped tube. Despite not having any of the other measurements of a polygraph, it appears to be nearly infallible... providing Murdoch is asking the right questions. Murdoch himself is the subject when he first demonstrates it for his colleagues, a demonstration very much PlayedForLaughs. Of course Dr. Ogden walks in, and the questions get very personal, and Murdoch is embarrassed by the accuracy of his own invention. Later episodes suggest that Murdoch is constantly working on improving it (because while it's always ''shown'' to be infallible, he keeps reminding us it isn't); in "A Study in Pink" it has a blood-pressure cuff, and the liquid tube has been replaced by dials, and by "The Ministry of Virtue", it has white and red lights for truth and lies.
* In ''Series/WhiteCollar'':
** In season 2, episode 6, Neal confounds a polygraph by pressing a tack into his finger during sensitive questions.
** Later, in season 3 (ep 1), a polygraph is used on Neal who tells the truth, but his questioner is still not convinced.
* On ''Series/{{ER}}'', after Doug tells him he has reconciled with Carol, best friend Mark teasingly asks him if she makes him submit to this as a condition (Doug cheated on her left and right the first time they dated).
* In ''Series/TheAmericans'', Stan tells Nina that she will have to pass the lie detector in order to be exfiltrated, thinking Nina was sincere with him. As Nina was a [[DoubleAgent double agent]] she was trained by Oleg on how to beat the test. [[spoiler:She did.]]
* ''Series/{{Monk}}'': For "Mr. Monk and the TV Star," Monk highly suspects TV star Brad Terry is guilty of murdering his ex-wife. For the benefit of the doubt, Stottlemeyer has Brad submit to a lie detector test, which he passes with flying colors. However, later, when Monk is talking with Brad in his trailer as Brad is working out on his treadmill, he notices Brad's heartbeat doesn't waver even as he lies to an assistant about liking her script idea, which leads Monk to realize Brad taught himself how to beat the polygraph.
* An episode of ''Series/TheGoodWife'' revolves around the idea that NSA employees are regularly given lie detector tests. The results are never depicted (including when a character answers a question regarding removal of classified files from the office while unsure if he technically did so), and it's implied that the tests are more about presenting questions intended to manipulate people into revealing their own mistakes or wrongdoings.
* The use of a lie detector was actually PlayedForDrama in an episode of ''Series/TheJeffersons'' where Lionel was offered a high paying job. At his interview, after answering all questions given to him, he was obligated to answer them again while hooked up to a lie detector. Feeling he was being denied his rights, he turned the job down, [[SkewedPriorities much to George's anger]].
* ''Series/{{Farscape}}'':
** In the episode "Dream a Little Dream," Chiana and Rygel must defend Zhaan against a murder charge on Litigara, a planet where 90% of the population are lawyers. One of the cornerstones of their legal system is the (generally considered to be metaphorical) "Light of Truth," which blazes brighter in the presence of lies. Chiana [[UnconventionalCourtroomTactics lights a broken chair leg on fire]] to serve as the Light of Truth when accusing a prominent lawyer of framing Zhaan. [[spoiler: The accusation is true, but Pilot is manipulating the stick from orbit.]]
** Another episode has a straighter example in the form of an alien [[VideoGame/HalfLife headcrab]] monster that was trained by the local merchant guild to sit on people's heads and stab through their skulls if they told a lie. It requires incredible force of will to fool, and Crichton would have been killed by it if not for the fact that [[spoiler: he had access to an identical twin for whom the statements he had to say were indeed true]]. The villain of the episode managed to deny all of his crimes with much effort, but couldn't successfully say a false answer to a big question that Crichton asked completely by accident: [[spoiler: "Well, aren't you just a good and loyal son?"]]
* ''Series/PersonOfInterest'':
** In "Booked Solid", Detective Carter is polygraphed for her application for the FBI, and worries that it will expose her association with Team Machine. Finch advises her to lie on an early question to skew the results. So Carter confesses to having smoked marijuana in college, and the polygraph operator congratulates her on being the first one to answer that question honestly.
** In "Proteus", Finch rigs up an improvised version with seismograph equipment, measuring the micro-tremors from the interviewees hands as they rest on the table.
* In ''Series/{{Wiseguy}}'' Frank [=McPike=] says he ExperimentedInCollege with marijuana. When Vinnie asks how he passed the polygraph when applying for the FBI, Frank says he didn't consider himself a user.
* ''Series/{{House}}'' once used a Cat scan as a lie detector, observing which parts of the patient's brain were active to tell when he was lying.
* ''Series/PennAndTellerBullshit'' has an episode on polygraphs and their operators. Their case study, a private contractor, uses the machine as his Bad Cop in a GoodCopBadCop routine (despite not actually being a police officer or affiliate).
* An episode of ''Series/AdamRuinsEverything'' has Adam debunk the usefulness of a polygraph, pointing out that even the machine's creator was horrified when he learned that cops were using it to seriously question suspects. Hell, the polygraph was once used to tell that a ''plant'' was lying. The cops then admit that they know it doesn't work, but they use it to PerpSweat ignorant suspects. Of course, the whole thing is an EngineeredPublicConfession to the audience.
* An episode of ''Series/{{Sliders}}'' has the heroes find themselves in a world where [[OppressiveStatesOFAmerica the US is under a martial law]], the Constitution has been banned, and [[ArsonMurderAndJaywalking all cops wear skirts]]. When Rembrandt goes to the police to trade the last known electronic copy of the Constitution for the freedom of a judge (one of the last "Constitutionalists"), the chief asks if he's willing to take a lie detector test to prove that they haven't made any copies of the disk. Rembrandt agrees, although the actual test is not shown. At the end of the episode, a copy of the document is emailed to everyone.
* One episode of ''Series/WorldsDumbest'' features a gadget called the "liar card" which acts like a phone version of a polygraph, telling you if the person you're talking to is lying. Of course, it also gives you the ability to lie to the other person with a fake phone number and/or a fake voice (which sounds like the classic "ransom demand" voice, for whatever reason); several commentators point out how morally gray this is.
* The British sketch comedy series ''The Russ Abbott Show'' had a sketch where the police tries to use a new kind of lie detector, which notices the lies by testing the voice and the suspect doesn't have to be attached to it. The interrogator ends up embarrassing himself when the machine buzzes at ''his'' lies ("I'm a very busy man!" "I am not a man to use violence!" "I can't be bought!")
* ''Series/TheGoodPlace'': Michael uses a cube which flashes green when someone tells the truth and red when they lie when investigating Eleanor. {{Justified}}, as the cube detects lies through explicitly supernatural means, so it makes sense that it would be faster and more reliable than normal lie detectors.
* In the live-action drama adaptation of ''Series/DeathNote'', L uses a polygraph on Light. He does not do so in the anime or manga.
* ''Series/BlakesSeven''.
** In "Dawn of the Gods", our heroes are able to beat this through ExactWords. The Caliph is seeking Orac, not realising it's actually a MasterComputer.
-->'''Caliph:''' The [[AgonyBeam neuronic whip]] is on an automatic setting. It has only to sense one lie and it will boil your brains in your skull. Where is Orac?
-->'''Tarrant:''' If he's not on the ship, I don't know where he is.
-->'''Caliph:''' How tall is he? ''(Tarrant demonstrates)'' A dwarf?
-->'''Tarrant:''' We never think of him as one.
-->'''Caliph:''' What is the color of his hair?
-->'''Tarrant:''' He hasn't got any. A bald dwarf shouldn't be too hard to find.
** The pilot episode shows that this trope doesn't work on someone who's been {{brainwashed}} to believe their own lies. Blake is framed for molesting children, and it's mentioned the accusers have all passed a lie detector test. However he's been framed by the government so they DontCreateAMartyr, and his lawyer discovers the children have all been taken out of school for unregistered medical treatment on the days they said they were assaulted.
** Vila insists that MasterComputer Orac verify an offer of Servalan's is genuine, apparently because [[RobotsAreJustBetter Computers Are Just Better]] at detecting these things. This is suggested in an earlier episode where a RebelLeader has been replaced by a Federation robot and kills a rebel who's become suspicious, because it would be able to pick up his body language showing that suspicion no matter how he tried to hide it.
* ''Series/{{Arrow}}''
** Early in the first season Oliver Queen is arrested on suspicion of being the Vigilante, and volunteers to take a lie detector test to prove his innocence. Laurel points out that such tests are inadmissible in court, but Oliver says it's for Laurel's father Quentin, the one who is suspicious of Oliver. Oliver passes, but Laurel notes a discrepancy: Oliver said he had never been to a specific location where the Vigilante had been seen, but Laurel knows he went there on a school trip as a kid. Normally that wouldn't be worth noting, he could have just forgotten, but there ''was'' a small blip on the lie detector, just not big enough to be registered as a lie. Laurel realizes that means he did lie intentionally, but kept his biometrics under control, meaning he could have been lying on any of the questions.
** In Season 2, a BatmanColdOpen has Oliver perp-sweating a lowlife while [[MissionControl Felicity Smoak back at the Arrowcave]] does an audio test on his responses to check for deception. She gets Oliver to ask what color his shoes are to get a baseline. Oliver complies despite knowing how silly he's going to look asking the question.
* An early punishment in ''Series/ImpracticalJokers'' involved Murr being hooked up to a polygraph and being asked increasingly embarrassing questions...to his entire alma mater.
* ''Series/TheTwilightZone1959'': In "[[Recap/TheTwilightZone1959S3E24ToServeMan To Serve Man]]", the aliens' representative agrees to a polygraph test, after a few test questions suggest it works on him (i.e., "How did you come to this planet?" "I walked.") the alien claims that their intentions on Earth are solely to help humanity, and the polygraph reads it as truth.
* ''Series/{{Elementary}}'': In "On the Line" a man accused of kidnapping and murder voluntarily takes a polygraph test to prove his innocence. Sherlock Holmes immediately works out that the man was tricking the machine (controlled breathing and biting his tongue on certain questions) to hide his guilt, but the evidence is in his favour so they have to let him go. Detective Gregson makes sure to note that polygraphs aren't considered reliable enough to be admissable in court.
* ''Series/TheWire'': besides the scene repeated from ''Homicide'' mentioned above, in season 4 when Greggs is investigating the death of a witness, she interrogates the man that was going to be testified against. After the test, the polygraph tech says the results are inconclusive, but heavily insinuates that he'll sign on either way if the police want.
-->'''Kima:''' no wonder this shit's inadmissible.

[[folder:Pro Wrestling]]
* In 2003, Wrestling/VinceMcMahon suspected that [[CharlieBrownFromOuttaTown Mr. America]] was Wrestling/HulkHogan in disguise (he was) and forced him to take a lie detector test. Mr. American passed when he said he wasn't Hogan. Angry, Vince took the test to prove it was rigged, only for the machine to buzz when he said things like he wasn't an asshole, wasn't a pervert, etc.

* Subverted in ''TabletopGame/{{GURPS}}: High-tech'' even if the polygraph works as advertised (by default it doesn't) the machine still doesn't detect lies, the interrogator is the one doing that. By ''Ultra-Tech'' lie detectors that operate on micro-expressions and brainwaves have been perfected.
* There's a short adventure from an early ''Magazine/{{Dungeon}}'' magazine, in which an elf suspected of murder steals a magical lie-detecting sword and flees before it can be used in his trial. [[spoiler: He's innocent, but knew that the sword also detected ''elves'', and was afraid its use to test his statements would ensure his wrongful conviction.]]
* The core rulebook for the "XP" version of ''TabletopGame/{{Paranoia}}'' includes a picture of an Alpha Complex citizen strapped into one of these. He's grinning and giving a thumb's-up, while behind him an enormous video screen blares the word LIE.
* A boxed ("board") game with versions called "Spy Detector" and "Lie Detector", which included a plastic machine that could indicate whether "witnesses" were telling the truth or lying about identifying characteristics of the spy or criminal based on holes punched in the "witness" cards and corresponding holes punched in cards placed in the machine.

* ''VideoGame/ClueSweeper'': You can buy one of these so that red herrings cost an additional penalty of 1 time unit instead of an additional penalty of 3 time units without a lie detector when found.
* The Magatama in the ''VisualNovel/PhoenixWrightAceAttorney'' series sort of works like this. Whenever Phoenix encounters a person that is either lying or is hiding a secret, the Magatama shows chains and locks over the person in question. The more locks there are, the harder it is to crack the person into spilling the beans. In one notable case, [[spoiler:this system is fooled by Phoenix's own client, who actually ''is'' the killer for once. He had the victim taken out by a hired killer, so when asked "did you kill him", he just says "no". Normally the Magatama sees through ExactWords of that sort by detecting the associated guilt, but it's implied that he's TheSociopath to the point that he didn't ''have'' any guilt over it.]]
* In ''VideoGame/TheSims2'' a lie detector can be unlocked as a career reward item for the criminal track, although in this case, the use for it is not to tell when someone is lying, but to increase a Sim's creativity skill by learning how to lie without setting it off (it will give the Sim an electrical shock if they fail).

* ''Webcomic/NSFWComix'' had [[http://nsfw-comix.com/nsfw336.htm an Independence Day comic]] where two fast food workers are interviewed by the secret service about the "secret ingredient" they added to President Obama's burger using a typical Hollywood Lie Detector.
* ''Webcomic/ElectricWonderland'' has Aerynn cast a spell that causes one's pants to [[KillItWithFire light on fire]] if he tells any lies.

* ''[[http://reynardnoir.wordpress.com/category/lie-detector Reynard Noir.]]'' Slylock simply tricks the perps into ''thinking'' it's caught them lying by raising their stress levels.

* Grandmaster in ''Literature/EnterTheFarside'' can have his helmet customised to include one of these. It can also pick on responses and relay back their tells and ticks. In [[https://enterthefarside.wordpress.com/category/arc-2-beginnings/2-3/ Beginnings 2-3]], Shaun believes Artifex used one of these on him.
* ''Website/SCPFoundation'': [[http://www.scp-wiki.net/scp-2128 SCP-2128]] is a stone furnace used as a torture device by a medieval cult. Whenever someone in the oven tells a lie, the SCP [[KillItWithFire incinerates]] them. This happens even for things the person doesn't know the truth of, and it has ways of avoiding [[LogicBomb paradoxes]]. [[spoiler: It's sentient, loves to eat human flesh, and isn't above roasting a truthful person.]]

* One episode of the Website/CollegeHumor game show ''Game Changer'' features a "lie detector" that shows a green light when a contestant tells the truth and a red light when a contestant lies. The questions start with easily-checkable queries like "What is your name?" and become increasingly personal, and, to the mounting astonishment of the contestants, the device correctly evaluates every answer despite there being no apparent way it could possibly work. It's eventually revealed that [[spoiler:the device is being operated remotely by the contestants' significant others hiding backstage]].

* ''WesternAnimation/TheSimpsons'':
** "[[Recap/TheSimpsonsS7E1WhoShotMrBurnsPartTwo Who Shot Mr. Burns? Part Two]]": Parodied when Moe was interrogated by the local police force and hooked up to a lie detector, which loudly exposes his attempts to mask his rather pathetic home life.
--->'''Tester:''' It checks out. Okay, sir, you're free to go.\\
'''Moe:''' Good, 'cause I got a hot date tonight. ''[buzz]'' A date. ''[buzz]'' Dinner with friends. ''[buzz]'' Dinner alone. ''[buzz]'' Watching TV alone. ''[buzz]'' Alright! I'm gonna sit at home and ogle the ladies in the Victoria's Secret catalog. ''[buzz]'' ... Sears catalog. ''[ding]'' Now would you unhook this already please? I don't deserve this kind of shabby treatment! ''[buzz]''
** "[[Recap/TheSimpsonsS8E10TheSpringfieldFiles The Springfield Files]]" , a FakeCrossover with ''Series/TheXFiles'', has Agent Scully hook Homer up to a lie detector and explain how it works. When she asks him if he understands what she's told him, [[EpicFail Homer says yes and the machine]] [[ReadingsBlewUpTheScale explodes]].
** "[[Recap/TheSimpsonsS13E22PoppasGotABrandNewBadge Poppa's Got a Brand New Badge]]": Bart tries out a lie detector, saying "Lisa is a dork!" over and over. Naturally, Lisa doesn't like that, but when Homer looks at the sheet, he says "According to this, he's telling the truth.".

* ''WesternAnimation/TheThreeLittlePigs'': The Disney short "The Practical Pig" (1939) features a lie detector, which notably [[HoistByHisOwnPetard goes off on Practical]] when, while punishing his brothers, he proclaims "This hurts me more than it hurts you!"
* ''WesternAnimation/BeavisAndButtHead'' were forced to take a lie detector test after being suspected of taking money from the Burger World cash register. Before they took the test, Butt-Head told Beavis that they can trick the lie detector by holding their breath. When Butt-Head steps up, the lie detector buzzes when he claims that he understands how the lie detector works but dings when he gets the number of fingers the man holds up wrong; when asked if he ever stole anything in his life, he passed out before he could answer. When it was Beavis's turn, he successfully convinced them that he was a serial killer from the 1960s, and he didn't even hold his breath yet.

-->'''Nixon's Head:''' Uhh... well, the question is vague. You don't say what kind of candy, or... whether anyone is watching... in any case, I certainly wouldn't harm the child. ''[truth-o-scope goes nuts]''
* ''WesternAnimation/TheFairlyOddParents'': In "[[Recap/TheFairlyOddParentsS2E4InspectionDetection Inspection Detection]]", Timmy's parents suspect him of stealing, so he whips out a lie detector to prove his innocence. Unfortunately, it ends up working against him when Mr. Turner asked where he got the detector and Timmy, [[RunningGag out of habit]], says "Internet".
* ''WesternAnimation/EdEddNEddy'' strap Jonny 2x4 to one of these in the PilotEpisode when they suspect him of stealing possessions from the children of the cul-de-sac.
* ''WesternAnimation/TheLoudHouse'': The ChildProdigy Lisa once developed lie detector technology and set up lie detectors all over the house, forcing the entire family to be truthful at all times. Eventually, Lisa comes to realize that sometimes a little lying is okay.
* ''WesternAnimation/ThePowerpuffGirls1998'': Every time the girls tell a lie in "[[Recap/ThePowerpuffGirlsS5EP10LyingAroundTheHouseBubbleBoy Lying Around the House]]," a mysterious little figure starts to grow until it becomes unmanageably monstrous. The girls can only defeat it by renouncing their lies and telling the truth. First implemented in issue #21 of the comic book ("Big Fish Story," DC run) in which the little fish the Professor caught grows with the girls' lies as it is manipulated by Him.

* ''WesternAnimation/BatmanAssaultOnArkham''. Harley Quinn tells Batman she doesn't know where the Joker has hidden a dirty bomb. The eyes on Batman's mask light up and we see a scan of her physiology (heart rate, pupil dilation, etc) which reads as normal to establish that she's telling the truth. Which raises some FridgeLogic — she had just fought Batman hand-to-hand, so why would her heart rate be steady?
* ''WesternAnimation/TheCrumpets'': The first episode has Ma building one and having her family tested so she can find out who kidnapped her husband.
* ''WesternAnimation/RickAndMorty'': In [[Recap/RickAndMortyS3E9TheABCsOfBeth "The ABCs of Beth"]], one item that Rick invented for Beth in her youth was a doll that very blatantly had a lie detector built in.
* ''WesternAnimation/TheDickTracyShow'': Hemlock Homes uses a lie detector (in the episode of the same name) on Stooge Viller and Mumbles. Not only does it tell when a lie is told, it [[SoapPunishment washes a culprit's mouth out with soap]] if a flat-out whopper is told.
* ''WesternAnimation/SpongeBobSquarePants'': In "Can You Spare a Dime?", Mr. Krabs becomes paranoid that Squidward stole the first dime the former ever made, and isn't very subtle about it:

* ''Series/TheTwilightZone1959'': In [[Recap/TheTwilightZoneS3E89ToServeMan "To Serve Man"]] the aliens' representative agrees to a polygraph test, after a few test questions suggest it works on him (i.e. "How did you come to this planet?" "I walked.") the alien claims that their intentions on Earth are solely to help humanity, and the polygraph reads it as truth.

* ''Series/{{Battlestar Galactica|2003}}''. In a flashback to before the war, Adama is seen applying for a job in which he must take a lie detector test. One of the baseline questions (used to establish the reliability of the other questions) is "Are you a Cylon?" (This was before anyone knew the human-looking Cylons existed). In a further irony, the man administering the test is himself a human-cylon.

* ''Series/GilligansIsland'': The Professor builds a lie detector out of -- what else? -- [[BambooTechnology bamboo and coconuts]] and tests all the men to find out who sent Mrs. Howell a love letter. One of the gags is The Skipper passing until he says, "See? I always tell the truth," which sets it off. [[BrickJoke At the end of the episode]], Gilligan is playing with it when Mary Ann comes in asking him what happened to a couple of coconut cream pies she made, and Gilligan denies seeing or taking them, [[ExplosiveInstrumentation which causes the lie detector to explode]].

* In the novelisation of ''Radio/{{Earthsearch}}'' by Creator/JamesFollett (also a RadioDrama), the Chief Prosecutor of the Solaric Empire interrogates Astra with two cerebral analysers focused on her brain. Lying modulates the beams causing a feedback "that you are unlikely to survive." So when Astra says that the spaceship she's from is unarmed and stranded in orbit around another planet, the Prosecutor thinks it's safe to kill the prisoners. Astra isn't lying; she just doesn't know that the asteroid DeflectorShields make a handy ImprovisedWeapon and the surgical androids can be reprogrammed to pilot the spaceship, which arrives JustInTime for a BigDamnHeroes.

* In ''Literature/{{Earthsearch}}'' by James Follett (also a RadioDrama), the Chief Prosecutor of the Solaric Empire interrogates Astra with two cerebral analysers focused on her brain. Lying modulates the beams causing a feedback "that you are unlikely to survive." So when Astra says that the spaceship she's from is unarmed and stranded in orbit around another planet, the Prosecutor thinks it's safe to kill the prisoners. Astra isn't lying; she just doesn't know that the asteroid DeflectorShields make a handy ImprovisedWeapon and the surgical androids can be reprogrammed to pilot the spaceship, which arrives JustInTime for a BigDamnHeroes.

* Literature/TheStainlessSteelRat beats being polygraphed by the secret police on a couple of occasions, once by working himself into an artificial state of panic before the test, then thinking boring thoughts during it. In another book he insists on a lie detector and is told the chair he's sitting in is one, causing him to think, "I'm glad I didn't know that when telling those other lies!" The Rat then proceeds to give a [[ExactWords truthful but misleading statement]] that clears him.
** In the first novel the Rat [[TrespassingToTalk breaks into the home]] of a politician and finds some handy blackmail material about numerous corrupt deals. The politician claims everything he's found is a FrameUp, whereupon the Rat reveals that the security robot holding the politician captive is also a lie detector. The robot confirms that 74% of everything the politician has just said is a lie...''except'' about the case the Rat is investigating. Their conversation then proceeds on a more amiable basis.

* ''Literature/KonoSuba'': After Kazuma is accused of deliberately teleporting a bomb to the governor's house, he is arrested and interrogated via a magic item capable of detecting any lies told in the vicinity. Even though Kazuma manages to convince the interrogator that he was genuinely trying to save the city, he accidentally sets off the lie detector by claiming to not be acquainted with any of the Demon King's underlings, having forgotten that Wiz is still one of his generals; as a result, he is misunderstood as being in liege with the Demon King's army and put on trial. When all seems lost and the judge is on the verge of pronouncing him guilty, Kazuma loses his patience and loudly asserts that he is ''not'' in liege with the Demon King or his army and that he is ''not'' a terrorist, which does not set off the lie detector and therefore is taken as truth. Unfortunately for Kazuma, the [[AristocratsAreEvil corrupt governor]] doesn't give a shit about his allegiance and threatens the judge into declaring him guilty anyway, [[ItsAllAboutMe since Kazuma did get his mansion blown up]].

-->--'''''Website/{{Cracked}}''''', [[https://www.cracked.com/article_85_6-bullshit-facts-about-psychology-that-everyone-believes.html "6 Myths About Psychology That Everyone (Wrongly) Believes"]]

** "[[Recap/TheSimpsonsWhoShotMrBurns Who Shot Mr. Burns?]]": Parodied when Moe was interrogated by the local police force and hooked up to a lie detector, which loudly exposes his attempts to mask his rather pathetic home life.

'''Moe:''' Good, 'cause I got a hot date tonight. ''[buzz]'' A date. ''[buzz]'' Dinner with friends. ''[buzz]'' Dinner alone. ''[buzz]'' Watching TV alone. ''[buzz]'' Alright! I'm gonna sit at home and ogle the ladies in the Victoria's Secret catalog. ''[buzz]'' ...Sears catalog. ''[ding]'' Now would you unhook this already please? I don't deserve this kind of shabby treatment! ''[buzz]''

* ''LightNovel/TheRisingOfTheShieldHero'' has an unconventional way to compel the truth through [[NotTheIntendedUse creative application]] of a Slave Crest. Slave Crests function as a MagicallyBindingContract between master and slave. When applied to someone, they become physically incapable of disobeying their master's orders. If they try to disobey the order anyway, the crest gives the slave a magical electric shock [[{{Geas}} until they do whatever it was that they were told to do]]. During a court trial, a Slave Crest can be applied to a witness with the judge as their master, who then orders the witness to "tell the truth". This would make the Slave Crest shock the witness if they lied in court. [[spoiler:This application of a Slave Crest is how Malty's FalseRapeAccusation against Naofumi gets dismissed; Malty is such a CompulsiveLiar that she can't help but lie in court, even after being told what the Crest would do and being shocked repeatedly from lying to the judge. Malty is eventually asked point-blank if Naofumi attempted to rape her; when Malty says that he did, she's zapped by the Slave Crest with such intensity that she's knocked flat on her back. Since it's clear that Malty is lying, the charges against Naofumi are dropped.]]

* The NAS report that led to the downfall of the device's widespread use pointed out that they said this about pretty much everyone they ever "passed".

* In the medieval RomanceNovel ''Literature/{{Enchanted}}'', the heroine has a friend of hers, a witch with this power, hold the hand of the knight who raped her so that she can interrogate him in front of her doubting husband. Once she's vindicated, her husband himself uses the woman's power to assure her that he believes her and is remorseful about not having done so before.