When someone takes the term "An Accessory to the Crime" to its logical conclusion.
Let's say that Alice murders Bob. You go after Alice; she's the murderer, of course. And the person who paid Alice to do it. And Alice's parents, who obviously didn't raise her to be a good person. And Alice's friends and family, who didn't hold her back. And the people who sold Alice the weapons she used. And the people who made the weapons she used. And the people who didn't pass laws preventing them from being manufactured and sold. And the society that, through its values, didn't make such a crime unthinkable...
In the more sympathetic portrayals, the Karma Police actually has a legit beef with the Villain by Proxy (who may or may not care either way), even if their methods can range from overzealous to cruel. The less savory examples operate under methods that come across as Misplaced Retribution, with a touch of Evil Is Petty, Never My Fault, or as a proponent of Poor Communication Kills.
A hybrid option would be to follow the slippery slope scenario, where it morphs from "directly involved" to "marginally involved" to "only acquainted with those who were involved". This is an effective way to descend the Karma Police into the path of He Who Fights Monsters.
Just for clarification, this is not about whether the audience feels this way about a character. This is about someone in-universe thinking this way and doing something about it.
Sub-Trope of Knight Templar with a touch of Well-Intentioned Extremist (depending on the portrayal). Compare Hitler Ate Sugar, Accomplice by Inaction, and Guilt by Association Gag, the former two of which can overlap if things turn really nasty.
- Villainous example early in Code Geass: Cornelia executes civilians in Saitama accused of secretly aiding guerrillas in the area.
- In One Piece, Admiral Akainu destroys an escape vessel that the other Marines had promised to spare on his suspicions that there possibly might be someone who could read the Poneglyphs.
- Used in some versions of Batman, especially the ones where he never learns who killed his parents (in many versions it's a small-time hood named Joe Chill, and even then sometimes he's long dead by the time Batman first appears or he's become a crime boss in his own right). In those cases, Gotham's criminal underworld as a whole is responsible for killing his parents, which is why he's just as willing to go after a Corrupt Politician or Corrupt Cop with the same intensity he would a street hoodlum.
- The Punisher: Frank Castle's family was gunned out during a family picnic shortly after Frank's return from Vietnam. Ever since, he's waged a one-man (sometimes two) literal war on crime of all kinds (Mafia, Mafiya, Triads, corporate, human traffickers...), despite the fact that the people responsible for the murders, and their associates, and the people they worked for, and the families they made up are long dead at his hands (especially in the continuities where Frank is pushing 60 and still at it).
- Some criminals try to point out that they have nothing to do with the deaths of Frank's family (heroes with a Thou Shalt Not Kill mindset often use the same argument when confronting Frank), which doesn't help them. The truth is that Frank is perfectly aware of this and isn't blaming them for it; he just wants to remove as much scum as he can before he inevitably dies and is reunited with his family.
- Notable aversion: in Batman: Year One, Bruce Wayne is turned off of studying the law when he learns about Accessory/Felony Murder laws, specifically a getaway-car driver being judged equally guilty of murder if his partner kills someone during a bank robbery, even though the driver wasn't even in the bank and doesn't know it happened.
Wayne: That isn't justice!
Professor: No, Mr. Wayne, that is the law.
- South Park: Bigger, Longer & Uncut: After the boys watch Terrance and Philip's R-rated movie and start cussing worse than they usually do, Sheila Broflovski leads the other parents to form Mothers Against Canada, who go on a campaign to ban all Terrance and Philips-related merchandise, eventually culminating in the duo's arrest and them being sentenced to execution for corrupting America's youth. When the Canadian government tries to get their citizens back, what does M.A.C. decide to do? Why, call for war with Canada, of course! This also includes setting up death- err, happy camps for Canadian-born citizens (even though Sheila's own adopted son Ike is Canadian) and will eventually result in The End of the World as We Know It. All because she and the other parents of South Park couldn't take responsibility for not being proper parents and keeping their kids from watching an R-rated movie.
- Ant-Man and the Wasp: Hank and Hope are on the run because Scott used their technology to violate the Sokovia Accords, even though he did it without their knowledge or permission.
- The Dark Knight: Harvey Dent is driven insane by having half his face blown off instead of being killed, because apparently Batman saved him instead of Rachel, and he goes on a coin-tossing rampage on everyone tangentially linked to her death. Joker, who planned the whole thing from the start, wins the coin toss and gets to live, so Harvey goes after the mob men and crooked cops he used to carry out his plan. The last person he targets is Commissioner Gordon, whose laissez-faire attitude toward the corruption in his department made the Joker's plan possible. But instead of taking it out on Gordon, Harvey attempts to kill his son, in order to make Gordon feel the pain of losing a loved one like with Dent with Rachel. This is the final straw that forces Batman to indirectly murder Harvey in order to save Gordon's son.
- Law Abiding Citizen: Clyde Shelton's family are murdered during a burglary, and the District Attorney cuts a deal with the burglar who carried out the murders, offering him a lesser sentence in exchange for him testifying against his accomplice (which sends the latter to death row). Shelton decides to take matters into his own hands, first by taking brutal revenge against both burglars, then by initiating a campaign of terror aimed at bringing down the entire justice system, which he sees as inherently corrupt and responsible for preventing justice.
- In Unforgiven, the working girls put out a $1,000 bounty on the heads of two cowboys, Quick Mike and Davey Bunting. While this is understandable in Mike's case (he cut up one of the prostitutes pretty badly), Davey's only crime is his poor choice of friends.
- In Now You See Me, The Fifth Horseman/Dylan's plan involves taking revenge on everyone involved with his father's accidental death. He uses the Four Horsemen to get his revenge. This includes the head of the insurance company that denied his family's claim, and the bank that held the note on it. It also includes the man who goaded his father into attempting such a dangerous stunt and the company that made the safe he used in the trick.
- In Guardians of the Galaxy, Drax has dedicated his life to killing Ronan the Accuser for killing his wife and daughter. After Ronan dies, he decides that he was just a pawn of Thanos, and that's who he really needs to kill.
- A major point of contention between the Space Wolves and the Inquisition in Warhammer 40,000. After the First War for Armageddon, the Inquisition decided that the Guardsmen and civilians who'd fought might be corrupted by Chaos (or start talking about what they'd seen about Chaos), and enacted a mass sterilization and forced labor program for the civilians and shot down the Guard transports. This did not sit well with the Space Wolves, who had fought alongside these men and women, and took it upon themselves to rescue all those that they could without opening fire on Inquisitorial ships. The Inquisition failed to take the hint and almost started a civil war with the Wolves.
- In the first book of The Saxon Stories, Ragnar tracks a man who betrayed him, and attempted to murder his adopted son, to a monastery. The bishop there tries to explain that the man is dying from his wounds and that anyone who seeks protection at a church is entitled to it. Ragnar grows more and more furious at the priest sheltering a man who betrayed his lord and attempted to murder a teenage boy, until he eventually decides that the priest and church must be evil if they allow evil men to take shelter, and slaughters the bishop, the rest of the monastery, and the man in question.
- In Frankenstein, Frankenstein's creation jumps off the slippery slope this way, by eventually extending his (previously justifiable) hatred of his abusive creator to cover Frankenstein's family, murdering people for the crime of sharing his bloodline.
- In The Goblin Emperor, there's an unusual example with Csethiro Ceredin. She is angry at the protagonist, Maia, and for good reason, because he forced her to marry him simply by proposing to her. However, she later tells him that she does not blame him and was actually angry at her family, who would never have allowed her to refuse the emperor. Played straight with Maia's cousin Setheris, who is angry at the emperor for banishing him to a remote country estate and assigning him as Maia's guardian ... and beats up the innocent Maia. Though Setheris himself never explicitly states that this is meant as revenge, it is implied that he was a much nicer person before his banishment.
- In A Song of Ice and Fire, Arya Stark's conflation of justice and personal vengeance leads her to this. While many of people on her death list certainly deserve to be brought to justice, such as the Tickler for torture and Weese for abuse, others were merely acting on orders, such as the Hound, doing their jobs or are just guilty by association. Cersei Lannister is on her death list for being involved in the execution of Ned Stark, but Cersei wasn't complicit in that activity, and even spoke out against it. Same with Ilyn Payne, who was just doing his job as the royal executioner. The real mastermind of Ned's death, Littlefinger, is not on the list. Meryn Trant is on the list for killing Syrio Forel, but there isn't any evidence to confirm the crime. Polliver and Dunsen are on the list for flimsy reasons, like stealing. She has Chiswyck murdered for the crime of not being as funny as he thinks he is (granted, Chiswyck was joking about a gang rape, but that isn't the reason Arya cites as his crime). The conflation of justice and vengeance, and how that conflation leads to this trope, is one of the key themes of the entire story.
- In Worm, it's revealed that there is a secret organization who make and sell superpowers, but do so by testing them on people, resulting in dozens if not hundreds of capes who have physically anomalous forms and no memories. The organization also sold powers to people who wanted to be villains and heroes, which resulted in a lot of death and destruction. When this all comes to light, those who bought powers are reviled by those who got powers naturally, even though the customers were not told the details of how the powers were made.
- And in the sequel Ward, the apocalypse destroyed the superhero union and pardoned/whitewashed thousands of supervillains out of necessity, leaving the general population paranoid that any cape on the street could secretly be an unrepentant, non-rehabilitated supervillain, and blaming the entire metahuman community for allowing one apocalypse to drive the world(s) insane.
- An unusual example occurs on Angel with the Vampire Hunter Holtz, who seeks vengeance on Angelus for murdering his family and forcing him to stake his own daughter. In this case, Holtz comes after Angel even after acknowledging that Angel is essentially a different person than the soulless Angelus. The trope is played straight in that Holtz's vengeance also encompasses Angel's infant son and his allies in Angel Investigations. Holtz's assistant, Justine, is also a clearer example, int that she hates all vampires because one of them killed her sister.
- On Buffy the Vampire Slayer, Warren shoots and kills Tara and is in turn killed in revenge by Willow. She also vengefully targets his former partners Jonathan and Andrew, despite their lack of involvement in the shooting... and when Buffy and the Scoobies prevent these murders, she blames and attacks them! And then she tries to destroy the world.
- Star Trek: Deep Space Nine:
- Sisko is an inversion, feeling this way about himself after playing a part in tricking the Romulans into declaring war on the Dominion. This includes bribery, manufacturing evidence, covering up the murder of a high-profile Romulan ambassador, and framing the Dominion for a crime they hadn't committed. It's easy to see his point, except he can live with it, if it meant preserving the Federation. At least, that's what he tells himself.
- A really interesting example in the episode "Dax". Ilon Tandro believes Curzon Dax was responsible for his father's death and wants him punished. Curzon is dead, but his memories and experiences live on in a symbiotic lifeform that was implanted into Jadzia Dax, so Tandro wants her charged with the crimes. Much of the episode centers around a court case to determine whether she, or the sybiote itself, can be considered to have culpability in such a case. The whole line of inquiry is made moot when it turns out that Dax was actually in bed with the murdered man's wife at the time.
- The Wire:
- Part of the utter, systemic failure of the drug war comes about because the police tend to treat anyone living near a drug-dealing operation with considerable brutality whenever such operations harm or even simply embarrass a police officer or a public official, and in turn most people living in drug-affected areas behave as if every police officer is a brutal thug or a Corrupt Cop because some of the police fit that description.
- In another example, when Corrupt Cop Major Valchek becomes enraged that stevedores' union chief Frank Sobotka has gotten a coveted stained-glass window at their church before Valchek, he sends his officers to harass the entire union with selective enforcement. Later still, frustrated that the investigation he instigates has moved on from Sobotka and the union to chase international drug and human traffickers, he calls in the FBI, knowing that they will focus on busting the stevedores' union first and foremost. By the end of the season, the union is gone, and by the end of the series at least some of the members are homeless after losing their jobs. Really, it's safe to say that the world of The Wire runs on this trope.
- CSI: NY:
- The Compass Killer. Driven insane from the grief and the brain damage that ensued from a madman entering his office and blowing away everybody inside with a shotgun (including his wife) before killing himself, architect Hollis Eckhart started killing everybody that had anything to do with it. The guy who sold the madman the gun, the shrink that didn't diagnose the shooter as an unstable man, the guard that didn't search the shooter thoroughly...and himself, for putting his wife in danger. It didn't help in any way at all that the madness which made him decide to perform these acts also made him identify innocent people as those that were the targets of his vengeance.
- After the team discovered he wasn't guilty of returning to his arsonist ways upon being released from prison at the beginning of season 9, Leonard Brooks resorted to this with all the people he blamed for being abused as a child...including his foster sister who was only seven years old at the time.
- Law & Order has numerous examples where the actual murderer gets a plea bargain relatively early in the episode so that the prosecutors can go after the "real villain"; these "real villains" included gun manufacturers/dealers, doctors/psychologists who prescribed/didn't prescribe medication, and the like.
- Law & Order: Special Victims Unit occasionally brought up a more valid version of this trope, where a perpetrator legitimately had something mentally wrong with them that was attributable to another person's actions, and where the other party in question should reasonably have been able to foresee that their actions could have drastic consequences. These include:
- A life insurance company that failed to report a prospective client's positive test for syphilis, either to the man himself or the health department (who would have relayed it to the infected person). Instead, the man's syphilis went undetected and was allowed to progress to the point where it destroyed his brain, which caused him to experience delusions that made him believe God was ordering him to kill people.
- A group home that intentionally withheld a schizophrenic man's medication to make him decompensate so no one would believe him if he tried to report them for negligence that caused the death of another resident. The resulting psychotic break led him to attack two people, one fatally, because he thought they were trying to hurt his son. The prosecutor has the group home manager charged with those crimes, in addition to charging him for the other resident's death, because the patient wouldn't have committed those crimes if not for the group home's actions.
- Agents of S.H.I.E.L.D. has Grant Ward. His need for 'closure' may fall into this. Bobbi Morse flat out states that there will always be someone he or his people need to seek 'closure' with, because that way he never has to take responsibility for his own role in screwing up his life.
- Shows up from time to time with unsubs in Criminal Minds. For instance, there was a vigilante who started targeting crimes in progress before moving onto known drug dealers and ultimately deciding to target the mother of the teen who killed his wife and then himself because better parenting should have prevented the crime.
- Person of Interest: In Wolf and Cub, Reese helped a young irrelevant number bring his brother's killers to justice. After the shooter and his accomplices are arrested, the boy insists on taking down their criminal boss, believing he was just as responsible, even though the murder was motivated by macho pride and sexual jealousy, not illegal business.
- Stargate SG-1: The replicas 'interrogate' Jack by torturing him with the day his son committed suicide on loop. This convinces him that all replicas are incapable of compassion, and he fires a temporal warhead at their home planet... right after Carter convinced one of the replicas that coexistence was possible. When he's called out on this, he is fully convinced that his decision to nuke all the replicas was right because their leader was a total sociopath. This ends badly.
- Fallout: New Vegas: The antagonist of the Lonesome Road DLC, Ulysses, hates the Courier because he blames them for the nuclear explosion that destroyed the Divide; it turns out the Courier once delivered a package to the Divide which contained the nuke's launch codes. The Courier, who makes a living out of delivering packages without knowing their contents, can't even remember the package clearly when Ulysses tells them what it was used for.
- From the very beginning, Ghost Trick makes a large deal out of the fact that various parties are trying to kill the female protagonist Lynne. At one point, the Big Bad tries to frame her for murder. Why? Back when she was a child, he was fleeing the police when he came across her playing in the park, so he took her as a hostage out of desperate opportunism. If she hadn't been there, he would have never gone that far. Therefore she was partially responsible for ruining his life, even though it was his choice to take her hostage from the cops that were already chasing him.
- Final Fantasy XIII has Hope. During his character arc, he blames his mothers death on Snow, who in fact saved her life and tried to dissuade her from leaving her child to take up arms, instead of the military that not only sentenced her to death in the first place but fired upon and killed her. Though a conversation with Lightning has him explain that he is after the military as well. So when he and Snow eventually patch things up, they can focus on taking them down alongside the rest of the party.
- Muramasa: The Demon Blade: In the PS Vita Updated Re-release DLC, Miike the nekomata starts killing everyone even remotely connected to her owner's murder, down to the servants who work for her enemy's clan.
- Touhou: The legendary Chinese archer Houyi shot down the nine suns that threatened to burn the Earth. Unfortunately, Junko's son was killed when one of them crashed on him, so she killed Houyi in revenge. Then she went after his wife Chang'e, who was held prisoner by the Lunarians... so she went to war with the Lunarians, by unleashing pure life on them (the Lunarians are big on immortality, so life (which, by definition, can die) is a Brown Note to them). Then she fights the protagonists who came to stop her.
- Gyakuten Kenji 2's mastermind is a deconstruction of what happens when a child happens upon a legitimate evil conspiracy that pulls the strings of an entire country and intentionally ruined their life; they became so thoroughly yet Properly Paranoid that everyone around them was working for the conspiracy, which was technically correct some of the time, since one of them is the president of a country - and then they used that as an excuse to hunt down the members of the conspiracy, regardless of their actual crimes or knowledge. The last target was a 13-year old boy who was the son of one of the conspiracy's victims and had no idea about any of this.
- In Goblins, Kore's Fantastic Racism extends not only to members of the 'monstrous races', but also to members of the 'civilized races' who could potentially harbor sympathy for monsters. This results in him executing a child whose 'crime' was being orphaned and Raised by Orcs, while delivering a speech about how allowing the child to live would result in the potential for greater evil to exist in future. Kore also uses two instances of a specific clan of Dwarves trying to stop him as evidence that he should hunt down and purge the entire clan.note
- A tendency for Double D in Ed, Edd n Eddy, who is often punished along with the other Eds by the other vengeful kids, despite most inconveniences they make are caused by Eddy's callousness or Ed's oblivious stupidity. This usually counts as Misplaced Retribution, but in one episode Sarah points out that Double D probably didn't have any part in the Ed's antics, but decides to let him take the fall anyway.
Sarah: It's like they say, give those cute ones an inch and they'll take a mile!
- TRON: Uprising has Cyrus, who believes that It Is Beyond Saving while the grid is under Clu's control and tried to eradicate everything, including the programs who don't support the occupation.
- The trope is parodied in The Simpsons episode "Brother From Another Series", when Sideshow Bob, actually innocent and reformed for once, actually helps Bart and Lisa thwart his criminal brother Cecil from sabotaging a construction project he and Bob are working on together. In the aftermath, Chief Wiggum sends him to prison along with Cecil on general principle.
- Rick and Morty: Despite Rick believing the Galactic Federation will torture his family until they confess to where he is, this trope is actually subverted when a Federation officer informs Rick over the phone that they only want him; allowing Rick to turn himself in while the others go free.
- Played straight with the New Galactic Federation in Season Four, who have no qualms with attacking/capturing relatives to, or clones of, their target for even the simplest signs of resistance.
- This is a common fallacy of numerous Moral Guardians who want revenge or justice on someone who commits murder after watching a television show or playing a Murder Simulator. This can go from the works' writers, to the producers or developers, channels who broadcast the show or stores that sell the game, anyone who had advertised in the production or promoted the show or game, sometimes escalating all the way up to anyone who watched the show or played the game.
- Gun manufacturers and sellers are sometimes sued if the people they sell guns to commit suicide, rape, murder, etc. with their products. American laws don't necessarily hew to this trope, and immunize manufacturers from being sued for criminal misuse of their products. Other manufacturers who make things that can easily kill people, even when working exactly as they should, are given the same protection (for example, you can't sue General Motors because a maniac used one of their trucks to plow into a crowd of people). A seller can only face charges if they sell to someone who the seller knows is legally prohibited from purchasing or owning weapons, such as a convicted felon.
- One of the reasons Jews were discriminated against for many centuries in Christian-dominated societies was the belief (however erroneous) that they were responsible for Jesus' crucifixion. Never mind that 1.) crucifixion was a Roman punishment, 2.) Jesus himself was Jewish, and 3.) the circumstances and significance of his death and resurrection form the central tenets of Christianity itself. Perhaps the worst offender was the German church under Adolf Hitler, a church which, rather than accepting that the Romans crucified Jesus on the basis that the Jews would never kill their own, claimed that Jesus was not Jewish on the basis that the Jews would never kill their own.