History Main / ConvictionByContradiction

** Or, for that matter, that only ketchup goes with french fries? Or that french fries are the only food ketchup goes with? It's a good thing this girl was a thoroughly stereotypical American with thoroughly stereotypical tastes. What would Encyclopedia have done if she'd brought mustard? Or ranch dressing? Or tatziki sauce? Or barbeque sauce? I like my french fries with bleu cheese, I could have stolen the taters and gotten off scot-free.

* WoodyAllen, in one of his books, wrote a parody of the detective-catching-one-mistake trope. The situations and answers were all absurd. For instance, a kidnapping victim returns home by asking his kidnappers if he could go to a football game that he only had one ticket for. The detective figures out that he's in on it with the kidnappers, because his parents are in their 80s and he's 60 years old, and "nobody would kidnap a 60-year old man, as it makes no sense."

* The perpetrator of a crime committed in a carnival is revealed to have been the work of the carnival magician due to the ''sole fact'' that he was wearing a short-sleeved shirt, and "since magicians pull stuff out of their sleeves, these must be long". Professional magicians almost always roll up their sleeves or wear short sleeves specifically to show that they're not hiding anything up there, to the point that, "Nothing up my sleeves!" is a cliche magician boast.

* A man tries to claim insurance money on a painting he's reported stolen. His story goes that while shaving after a shower, he saw reflected in the mirror a man stalking away with the painting. Encyclopedia explains that the claim is a fraud because a mirror would be foggy after a shower and so the man wouldn't have been able to see anything. (Never mind that it only takes a second to wipe away condensation, something people often do when they need to ''shave''. Or cold showers, or how movement and shapes are still discernible through a foggy mirror. Or how some people use a fan or leave the bathroom door open specifically so that the mirror doesn't fog up in the first place!)

->"'' '''Objection!'' '''

*** Then they do [[WriterCopOut a complete cop out]] by having an utterly random third party unconnected to the case stab him to death.

* Inverted in the SherlockHolmes story ''The Boscombe Valley Mystery'', wherein Holmes identifies the true killer and gets him to sign a confession, but promises to only use it if the falsely accused man who's being tried for the crime is in danger of being found guilty. This is averted when Holmes presents a number of his findings to the accused man's defence attorneys, who use it to get their client acquitted, and the SympatheticMurderer who actually committed the crime dies several months later.

* It is commonly believed (if not [[LittleKnownFacts well-known]]) that an innocent person accused of a misdeed will deny it, while a guilty person will say "you can't prove that!" As pointing out that the accusation is [[ConvictionByContradicton by contradiction]] rather than evidence is closer to the second reaction than the first, it's not unreasonable for {{lampshading}} this trope to trigger a (further) investigation.

* The perp claims to have seen something by moonlight on a night when there was no moon. (Because mistaking some other light source for moonlight is clearly criminal.)
** On the other hand, [[AbrahamLincoln a lawyer you may have heard of]] won a case in [[http://en.wikipedia.org/wiki/William_%22Duff%22_Armstrong exactly this manner]] but he used it to get an acquittal, not a conviction. This may have inspired the plot.
*** On the gripping hand, that strategy is a lot more plausible in the 1850s than a hundred years later. Depending on the location of the alleged murder (for one thing, whether it's in a rural area or not) the moon may really be the only light source bright enough to see something 150 feet away at night in 1858. The Encyclopedia Brown stories were written starting in the 1960s and generally set in suburban America, though, so what worked in Lincoln's day wouldn't work in Brown's.
* A boy comes up with an alibi but in the process traces a shirt pocket on the wrong side of his chest. Obviously, he's lying. (Because nobody would just forget what side of their chest a pocket is on.)
** This is doubly suspect since there's yet another perfectly reasonable explanation -- in general, you often see your shirt (and the pockets) while looking in a mirror, so you may inadvertently flip left and right while drawing it from memory.
*** ... What kind of Alibi involves drawing a picture anyway?
* A man accused of committing a robbery is being interrogated in the crime scene and claims he has never been there before. Shortly afterward, he says the words "When you brought me ''back'' here, did I resist?" to the police officer. Since he couldn't be brought back if he had never been there before, the man is guilty. (Again, people who make small semantic errors are obviously lying. Plus the suspect may assume that the police had gone to the crime scene, decided upon their suspect, and then brought him '''back''' to it.)
** Also, some people would simply see it as being brought "back" somewhere as in "away from where I was". "You brought me back to the police station" would have been just as true even if the guy had never been there. Grammar Nazis turned prosecution must be a bitch in that universe.
* The perpetrator of a crime committed in a carnival is revealed to have been the work of the carnival magician due to the ''sole fact'' that he was wearing a short-sleeved shirt, and "since magicians pull stuff out of their sleeves, these must be long". (Because no magician has ''ever'' specifically learned sleight of hand that can be done with short sleeves, precisely to remove the possibility of something coming or going from the sleeves from the audience's mind.)
* The perp claimed to have been on the bottom floor of a building when the crime was committed. Yet when he went to the elevator, he pressed the up button, when there is no down button on the bottom floor. (Because the fact that the one button goes up has nothing to do with why he called it that.)
** This one is actually a rare [[JustifiedTrope justification]] for Encyclopedia since, for once, the flaw is ''not'' used to prove that the perp is lying/guilty. In this story, the perp (more of a harmless kook than outright criminal) is actually sorry about what he did and is trying to make amends. The problem is that he recalls throwing away a key in the bottom floor of City Hall, the sub-basement, and the sub-basement's trash bins were all emptied the next morning before the key could be found. The fact that he claims that he left the floor by pressing the up button of course "proves" nothing. But it might ''reasonably indicate'' that ''maybe'' the perp was mistaken about what floor he was on. Encyclopedia reasonably deduces that maybe the perp was in the basement, not the sub-basement, when he threw the key away (granted, Encyclopedia typically acts as if it's a dead certainty, when all it really is is a possibility). The trash bins of the basement are searched, and sure enough, that's where the key is found (fortunately, the basement and sub-basement have different schedules for taking out the trash).
* The perp claims to have put a bookmark between two pages that are normally on opposite sides of a leaf. (Because there's no such thing as a misprinted book -- or the chance that he just gave the wrong page number.)
** Honestly, knowing the exact pages you were on without having the book in front of you is considerably more suspicious than not knowing them. (It implies you were rehearsing what to say.)
** Also, if you can consistently remember which page you're on, you don't need a bookmark.

* A supposedly unsolvable mystery occurs when a large, strong female is assaulted in the ladies room of a restaurant. The assailant couldn't have been a woman, since a woman can't knock out another woman that large with one punch. But it couldn't have been a man, since a man would have caused an outcry in the ladies room. [[strike:Encyclopedia]] his female sidekick deduces that it was a man ''dressed'' as a woman, since he previously saw this "woman" sitting in a booth of that restaurant, along with a male companion, on the side of the booth where she could not "see and be seen". (Because people follow ''every little mannerism'' someone threw into an etiquette book.) As well, Sally's characterized as the type of tomboy who wouldn't care about such etiquette, as well as the kind of CuteBruiser who could have knocked out the woman herself.
** Plus Sally was the only person there who'd ever heard of this little rule, and yet the solution assumes everyone knows about it and practices it.

** Especially stupid because the non-express lanes could have been, oh, I don't know, empty? It could have been a slow day so there weren't many people there; and even if there were a lot of people there, the people in front of him in the lane could have gone really fast, or not have many items.
* Bugs Meany holds a raffle drawing at a fair for a baseball glove and has one of his friends [[DoesThisRemindYouOfAnything reach around for another associate's balls]] in the big container of ping-pong balls. Encyclopedia discovers he was cheating by noticing that Bugs drank a canned soda when he was carrying around a thermos, thus meaning he put the ball in the freezer then took it to the fairgrounds in the thermos, so the associate would just have to feel around for a frozen ball, picking the one of a close friend of Bugs'. (Because thermoses always keep things cold, never hot, and because no one ever finishes what they have in the thermos then wants something more to drink.)

* In ''InglouriousBasterds'', Hicox is doing a good job of staying undercover... until, rather suddenly, the German soldier he's been talking with says that he's given himself away. The audience is not told what the mistake was until much later: He used the British hand gesture for "three" (index, middle, and ring fingers raised) instead of the German one (thumb, index, and middle fingers raised).
** For German audiences, that mistake was easily noticeable. It sounds contrived but most German viewers noticed that it wasn't the "German three."

* In a book of tales of the wise Japanese judge Ooka Tadasuke, in one story he calls for a tree to be brought in to testify. The defendant protests that that this will take too long, revealing that he knew details about the tree's location, contradicting his claim to have never been to that area.

* Inverted in the SherlockHolmes story ''The Boscombe Valley Mystery'', wherein Holmes identifies the true killer and gets him to sign a confession, but promises to only use it if the falsely accused man who's being tried for the crime is in danger of being found guilty. This is averted when Holmes presents a number of his findings to the accused man's defence attorneys, who use it to get their client acquitted, and the SympatheticMurderer who actually committed the crime dies several months later.

** Inverted ''again'' in another story where Archie accidentally spills paint remover on an 1870 Frederick Church painting that Mr. Lodge buys from an art dealer. Mr. Lodge is predictably upset, but then Archie wipes away more paint and finds the signature "Picasso". Mr. Lodge is suddenly thrilled, thinking that he's actually discovered a long-lost painting by PabloPicasso, but then his butler Smithers reminds him that Picasso was born after 1870, the date when Church supposedly painted his picture. When Mr. Lodge realizes that Church couldn't have painted over Picasso's original painting if Picasso wasn't even ''born'' yet, Mr. Lodge realizes that he's being conned, and takes back his check from the crooked art dealer, who Lodge and Smithers then literally throw out of the house.

* One early {{Supergirl}} comic featured a woman impersonating a man claiming to be Supergirl's husband-that-she-forgot-she-had, in order to make her (the woman's) boyfriend give up his crush on Supergirl. Supergirl saw through this at the beginning, because the woman put "his" arms around Supergirl's neck when "he" kissed her rather than around her waist, which is apparently something ''only'' girls do.
** Shouldn't she be able to, you know, ''literally see through the disguise'', being as she is Supergirl?

**The fact that he has to point out the actual clues in order to get the cops to believe him in the first place indicates that yes, the evidence is what matters. Shawn's visions are pretty obviously not part of the legal proceedings, they're just the mechanism by which the cops find the hard evidence they need to prosecute.
*** It was also mentioned in an episode last season that they have something like an 85% conviction rate for cases they're involved in.