The cart comes rumbling up to the gates. The Evil Overlord's guards poke about, and find a jug under the seat. Fool peasant thought he could sneak some moonshine past them. They take it, and the cart rumbles on — with the rightful king hidden under its cargo.
Infraction Distraction is when a conspicious but minor infraction — possibly not even illegal but merely disreputable — is made up or committed for the purposes of distracting authorities from something much more serious. Not unlike a Kansas City Shuffle, the guards in question know they're being tricked, but are wrong about what the trick is. If you actually confess, it's Confess to a Lesser Crime, but you can also manufacture evidence against yourself or otherwise plant clues to the infraction. One common method is to plant an Incredibly Obvious Tail — to distract from the skilled and subtle tail; Incredibly Obvious Bug can also be used but is less common.
Overlaps with Embarrassing Cover Up if the decoy secret is disreputable as well as prohibited (or if the character is so Lawful Good or such a Slave to PR that being caught breaking even minor rules is an embarrassment in and of itself). Overlap with We Need a Distraction is possible but rare, since it usually is not to enable further actions. If a character points out some other, unassociated character's wrongdoing, that's Go Look at the Distraction. If a suspect is surprisingly quick to confess their Big Secret, there's a good chance it's this. See also Hidden in Plain Sight. A Censor Decoy is this used in Real Life to get crap past the radar.
Anime and Manga
In the first chapter of Bloody Monday, Fujimaru (a teenager) tells his younger sister he's going to check out his porn downloads, just so she doesn't enter his room to catch him hacking. It's suggested that he also used porn video games as a cover for hacking jobs, though it's never denied that he played them.
This is one of the many tactics employed by Light in Death Note to hide his possession of the titular book. When he realizes that his room has been bugged, he lets them catch him reading porn, in order to make it appear that his security-precautions were put in place to prevent his parents or sibling from finding his Porn Stash.
Similarly, Madarame from Genshiken had some porn DVDs in a drawer to serve as a decoy to prevent the other club members from discovering something else in that drawer: photos of Kasukabe cosplaying.
Inverted in the plots of the first and third Die Hard movies; thefts are disguised by terrorist attacks.
This joke (various local permutations exist):
Tuan comes up to the border between Vietnam and China on his bicycle. He has two large bags over his shoulders. The guard stops him and says, "What's in the bags?" "Rice," answered Tuan. The guard says, "We'll just see about that. Get off the bike." The guard takes the bags and rips them apart; he empties them out and finds nothing in them but rice. He detains Tuan overnight and has the rice analyzed, only to discover that there is nothing but pure rice in the bags The guard releases Tuan, puts the rice into new bags, hefts them onto the man's shoulders, and lets him cross the border. A week later, the same thing happens. The guard asks, "What have you got?" "Rice," says Tuan. The guard does his thorough examination and discovers that the bags contain nothing but rice. He gives the rice back to Tuan, and Tuan crosses the border on his bicycle. This sequence of events is repeated every day for three years. Finally, Tuan doesn't show up one day and the guard meets him in a noodles restaurant in Vietnam. "Hey, Buddy," says the guard, "I know you are smuggling something. It's driving me crazy. It's all I think about..... I can't sleep. Just between you and me, what are you smuggling?" Tuan sips his beer and says, "Bicycles."
Here's a Snopes page with more variants on the "stealing bicycles" joke.
Robert A. Heinlein loved this trope, not only using it but making it a piece of wisdom for the Mentor to hand on.
In Starman Jones, Matt hitchhikes with a truck driver, who has him sleep in the bed and explains that he will be the off-duty driver all the time, with the driver with him driving longer than regulations permit without sleep. When they hit a checkpoint, the driver is caught not having his asleep partner having signed off, and explains to Matt that it kept the guard from digging deeper.
In "If This Goes On. . . ." Zach covers up Johnny's obviously guilty reaction to receiving a note from the Resistance by replacing it with one about gambling, because they won't believe innocence but will believe this.
In Podkayne of Mars, the main character's brother makes a crack about smuggling drugs onto the space ship, thereby preventing the guards from discoving the bomb he hid in her luggage.
In a Labyrinth, when caught trying to break into a genetic engineering facility, one of Miles' subordinates quickly posed as a horny soldier on leave who thought it was the brothel (the company is known for its bordellos). The subordinate got booted out with a warning; Miles, already inside, was safe, though isolated.
One of the stories about one of Miles' ancestors has him using the smuggling bicycles tactic, to smuggle horses into a besieged city. Miles does it with warships.
In Mary Steward's This Rough Magic, Godfrey admits to smuggling to distract from his actual attempts at destabilizing nations with counterfeit currency and attempted murder.
In Codex Alera, Captain Demos lets a few port inspectors find some assorted contraband to keep them from searching too thoroughly for Varg.
In A Deepness in the Sky, Pham Trinly pretends to secretly be an old slave-trader he knew once, letting the villain currently in charge 'discover' it and think he therefore has Pham squarely under his thumb. This "small lie to cover the big one" hides the fact that he is actually Pham Nuwen, the legendary trader, space navigator and politician, and by far the most dangerous person in the fleet and easily the greatest threat to the villain's rule.
The Boy Who Knew Too Much by Roderic Jeffries. A youth breaks into an abandoned factory on a bet and finds himself pursued by masked thugs. He has trouble getting anyone to believe him, but a few days later someone steals the copper piping from the building, so the police think that's what it was all about. It's only when the boy remembers that he saw one of the men looking through a telescopic sight that the police realise the building overlooks a nearby prison, and the criminals are planning a jailbreak.
Subverted in Frasier. After finding out that his wife Daphne broke into his confidential files in order to learn more about a patient with a crush on him, Niles furiously reads her the riot act on the seriousness of breaches of doctor-patient confidentiality, and exclaims "This is the absolute worst thing you could have possibly done!" Daphne pauses for a moment, then says "You would think so", before reluctantly confessing that actually, she had then stalked the patient in question, used Roz to gain access to the patient's office, and ransacked the place looking for information.
Another episode plays it straight, when the Cranes while on a road trip end up taking Daphne into Canada without realizing that her working visa doesn't permit her to cross the border. When they get pulled over by customs on re-entering the United States, everyone's guilty-trying-not-act-guilty appearances immediately convince the customs official that something's up, leading Martin to reluctantly reveal the truth... he doesn't have a permit for Eddie (the dog) to enter the country. On learning that Martin's an ex-cop, the customs official is satisfied with Martin's explanation and lets them pass without ever learning about Daphne.
A variation in Sherlock, episode The Great Game: Sherlock immediately deduces that Molly's new boyfriend Jim is secretly gay. Jim plays that particular role so that Sherlock would ignore him due the belief that the former's interest in him was a mere romantic infatuation, which covered up the fact that he was interested in Sherlock because he is Jim Moriarty, Diabolical Mastermind and the show's major villain.
Dexter later manages an accidental example when Doakes catches him at a Narcotics Anonymous meeting, which he was only attending as part of lie for his girlfriend. It gets Doakes off his case, at least for a while.
Buffy the Vampire Slayer. In "Band Candy" Buffy tells her mother that she's training with Giles, then tells Giles that she needs to help her mother. She then goes off to care for Angel, who she hasn't told anyone is Back from the Dead. She goes home to find Joyce and Giles there comparing notes, so Buffy lets them think she's been neglecting school and Slayer duties by partying at the Bronze.
Paranoia: A few citizens have registered mutations they don't actually have, such as chronic runny nose (his real mutation was about to be reported, but citizens with multiple mutations are nearly unheard of) or temporary blindness (so he could take bribes from fellow traitors to look the other way).
Done frequently in the Ace Attorney series - some villain or other will use a minor crime as a cover for a far larger one, in some manner or other. For example, in the third game, a villain arranges for himself to be caught on video committing theft, in order to give himself an alibi for a murder that took place at the same time. In Ace Attorney Investigations, another villain sets up a justified self defense murder to cover up a premeditated murder. Many other examples throughout the series.
Not really many. As far as a count, there are three times when it happens, which compared to the number of murders and cases in the series as a whole is practically nothing. Of course, killers always commit perjury on the stand, however apart from the three examples in which they confess to a smaller crime, these lies are intended to be that...lies, and so they expect people to not even know they committed a crime anyway.
This is the principle behind "deniable encryption" systems, designed to address the situation where someone in possession of encrypted files is coerced (by physical force or plea bargaining, say) into handing over the decryption key. These systems allow data to be hidden on several different "layers", each requiring a separate key to access the data - for example, someone could store their porn collection at the first layer, squickier porn at the second layer, and military state secrets at the third. The trick is that it's mathematically impossible for the interrogator to know how many layers are in use (and it is also possible to have more than one volume at the same layer, for example having two second- or third-layer volumes), since anything they haven't decrypted yet is indistinguishable from random garbage - so at any point the subject can plausibly claim that they've handed over all the keys they have, and the interrogator has no way to be sure whether they're dealing with an actual spy or just a very paranoid pervert.
After 9/11, TSA employees were rigorously trained to catch the various items newly banned from airplane carry-on baggage. A test of the system found that the security officers would often spot a lighter - and miss the bomb parts in the same bag.
If one is being almostcaught doing something (be it porn or a Guilty Pleasure or something else), it's always better to have something else to be "caught" with, thus explaining both being flustered and avoiding the Awkward Silence that occurs when you are found staring at your blank desktop all the time with. As one YouTube commenter put it:
Commenter: My mom walked in while I was watching MLP. Luckily I managed to alt-tab to my porn.