Absence of Evidence

"Gregory: Is there any other point to which you would wish to draw my attention? Holmes: To the curious incident of the dog in the night-time. Gregory: The dog did nothing in the night-time. Holmes: That was the curious incident."

- The Adventure of Silver Blaze

Sometimes the absence of a thing is a vital clue. For example, the absence of fingerprints on an often-used item makes it clear that the item was cleaned. A tool missing from a set could well be the murder weapon.

This is a real life area of detective work and, in fact, one of the harder ones. The lack of something is easy to miss. However you have to be careful. The lack of gunshot residue on a person's clothes for example does not mean that there was not a gun fired, it means that there is no residue from a gunshot. Lack of such residue on the glove that an eye witness saw the alleged firer use and then dump that is immediately picked up by the police might show that the event was staged however (as such evidence should have the residue and there is no way it might have been removed.).

Can lead to a Conviction by Contradiction situation if poorly handled.

Compare I Never Said It Was Poison, where someone incriminates themselves by mentioning details which were withheld from the public.

Anime and Manga

 * In an episode of Case Closed, the daughter of a wealthy businessman has been kidnapped and Conan figures out who the kidnapper is when he remembers that no one reported hearing the sounds of dogs barking the previous night. (For clarification, the butler who claimed to have witnessed the kidnapping said that the kidnapper climbed down a tree, but the businessman's dogs routinely barked at anyone who got near the tree.)
 * In Monster, Johan's crime scenes are devoid of feeling. In one arc, this enables Runge to determine that a certain murder was committed by a copy-cat and not Johan.

Comics

 * In the first Judge Dredd comic in Hondo-Cit, the Hondo-Cit Judge works out that the assassin he is chasing is a robot because there is no rollmat, no food, no toothpaste, etc., in his apartment.
 * This was, oddly enough, used to discover Superman's secret identity back in the Silver Age of comics. Superman has since started filling his bathroom with all the things needed for daily life, and putting medicines in his locker.
 * In the DC one-off "World Without Grownups" (a Prelude to Young Justice), it appears as though all the children in the world have disappeared. However, Batman deduces that the ADULTS were the ones who were transplanted to a parallel earth when he notices that none of his bat-gear has any dust on it (and then proceeds to carbon date everything he can find to back up his hypothesis).

Film

 * One of the final reveals in Rashomon is that the woodcutter, who at that point was the only person the viewer would be inclined to believe entirely,, but the object was never mentioned by him.

Literature

 * In the story "Silver Blaze" that gives us the page quote, Sherlock Holmes points out the vital non-clue of a dog failing to react to a mysterious visitor... when a guard dog doesn't bark at an intruder it generally means it's someone he doesn't think is an intruder at all.
 * The absence of certain valuable deeds is a vital clue in The Norwood Builder.
 * In one of the Union Club Mysteries by Isaac Asimov, Griswold points out that the female suspect they are looking for (who has been shown to be fanatical about stockpiling supplies she will need) must be post-menopausal as there were no products for dealing with menstruation in her apartment.
 * Another, perhaps less convincing, story has Griswold show that a suspect is only pretending to be a writer because there is no wastepaper basket in his apartment, which would have fairly standard for a writer at the time.
 * In the Death Note novel, this was the basis for all of Beyond Birthday's clues: "Something that should be there, but isn't."
 * The Lord Peter Wimsey mystery The Five Red Herrings turns on the absence of from the crime scene.
 * In the Sword of Truth novel Chainfire, after the eponymous spell has made everyone forget that Kahlan ever existed, Richard tries to use this to convince everyone else that she has. He points to where he says he, Kahlan, and Cara had been walking, and notes that there were no footprints between his and Cara's, which were several feet apart. He tells his companions that this means someone erased Kahlan's footprints. Nobody believes him since, as mentioned, everyone is sure that she never existed in the first place.
 * This trope is referenced in the first novel of the Bernard Samson series. While Bernard is in custody of an East German intelligence officer, they discuss the story of Silver Blaze. Bernard then points out the equally curious omission of any attempt at a proper interrogation. The reason for it is.
 * Sisterhood series by Fern Michaels: This is one of the reasons the criminals do not get punished legally and the innocent get punished instead. Lethal Justice has prosecutor Jack Emery being told by the wife of Roland Sullivan that Roland and Arden Gillespie are intending to commit a crime. He is reluctant to pursue legal action, because he has no evidence. He does promise to look into it...and he has to turn to the Vigilantes to help bring down those two criminals!
 * In the Honor Harrington novel Echos of Honor, a State Sec general figures out that the prisoners have taken over the prison because the warden failed to send his next chess-by-mail move.

Live Action TV
"Adrian Monk: Her lipstick? Captain Leland Stottlemeyer: Yeah, what about it? Adrian Monk: It's on the cup. There's some on her lips. But it's not here; it's not in her purse. What happened to the lipstick? Natalie Teeger: He took her lipstick?"
 * Monk
 * They mention a case that looked like suicide until Monk pointed out that there was no water for the overly-large pills on which the victim had OD'd.
 * In "Mr. Monk Goes to a Rock Concert," the clue that suggests to Monk and Natalie that a roadie did not die of an overdose in a port-a-potty is a lack of mud on his boots that would have been present if he'd walked through the muddy patch around the bathrooms.
 * In two episodes, "Mr. Monk and the Astronaut" and "Happy Birthday, Mr. Monk," Stottlemeyer concludes that someone else has been to a victim's place of residence from the fact that a computer is missing.
 * In the serial killer case documented in the Show Within a Show in "Mr. Monk's 100th Case," this is shown when Monk is at one crime scene, and later turns out to be a clue that allows them to tie the victim to a serial killer:


 * In the Deep Space Nine episode The Nagus, one of the things that tips Odo off that Zek is not dead is the absence of Mairhar'du at his funeral.
 * Played for laughs in Friends. Joey gives Chandler his show reel in order to be considered for an advert being produced by Chandler's company. When Chandler claims to have watched it, Joey says that he obviously hasn't, because part of the audition tape was an advert Joey did where he wore "Lipstick for Men", which Chandler would have definitely made fun of.
 * Columbo: The episode called "The Most Crucial Game" has the culprit caught when.
 * Raines uses this in the episode "Reconstructing Alice", with a dog that didn't bark, as in the Sherlock Holmes story. Raines even quotes Sherlock Holmes when realizing this.
 * Law and Order had a case where they realized the killer was following the instructions in a book about how to kill someone and get away with it ("for educational and entertainment purposes only," of course). When they caught the killer and confronted him with all the things he did to (successfully) avoid leaving any clues as to his identity, he responded, "So I'm guilty because you don't have any evidence?"

Video Games
"Phoenix: So... were any fingerprints found on the gun? Klavier: ...Unfortunately, no. Of course, the defendant is known for wearing gloves. We might say that a lack of fingerprints is, in fact, a "fingerprint" of its own."
 * Ace Attorney
 * For example:


 * Later in the same case, the victim's insulin syringe was completely empty, adding weight to Phoenix's claim that the killer put something else in it.
 * In the 5th case of the first game (MAJOR spoiler):.
 * In the first case of Ace Attorney Investigations, the killer claimed to have lost his keys and asked a security guard to open the door to "his" office for him. The absence of the security guard's prints on his door suggests that.
 * In a later case from Investigations, the absence of blood on the hilt of a knife that was found inside a victim suggests that

Visual Novel

 * In Higurashi no Naku Koro ni, Rena noticed that the bottle of shoyu in Rika and Satoko's house was missing, and deduced the possibility that they had visited the Sonozaki estate that night with an empty shoyu bottle and been kidnapped.

Western Animation

 * In Justice League, when Superman is apparently killed by Toyman's latest machine, Bruce refuses to believe it, and presents his theory to Alfred by saying the lack of evidence is what tipped him off--Toyman's weapon left no trace evidence. It left no debris, so it didn't blow him up. It left no burns, so it didn't incinerate him. It didn't even leave radiation, hence it didn't disintegrate him. Bats decides that since Toyman is merely an obnoxious Mad Scientist, not a god, the Law of Conservation is still in effect, and therefore Superman couldn't have just been destroyed. His conclusion; it teleported him somewhere., but the show doesn't make it clear whether or not Batman is simply in denial.

Real Life

 * The Bielefeld Conspiracy meme parodies Conspiracy Theories which run on this. Basically, it posits three questions to the person: Do they know anyone from Bielefeld, have they ever been to Bielefeld, and do they know anyone who has been to Bielefeld. Since most people are expected to answer no it is concluded the Bielefeld doesn't exist. People who answer "Yes" to the questions are said to be working for the conspiracy.
 * Commonly used as an argument in favour of Atheism, although believers are quick to point out that this is only true for some values of "evidence". Agnosticism uses the same argument, but adds that 'absence of evidence is not evidence of absence' (that a lack of proof does not itself constitute a disproof), and that, therefore, the Atheists are speculating beyond the data on this one. The standard Atheist defense to this is to point out that extraordinary claims require extraordinary evidence, and that it's the believers who are making the extraordinary claim. It's all very complex.