In many cultures, taking someone's life is considered one of the worst things you can do to a person. That being said, there's one circumstance where it will often be considered justified: self-defense.
Enter Killing In Self-Defense, where an assailant is killed by whoever they were trying to harm. This can come in a variety of ways, maybe there was the would-be victim managed to fights back and manages to kill their assailant in the ensuing struggle, or perhaps the would-be victim knew in advance that they would be targetted and took steps to outgambit
If the assailant was out to kill the victim, then it's essentially Karmic Death
at its finest.
Compare Assassin Outclassin'
, which encompasses all instances of foiled assassination attempts.
Since this is a Death Trope
, expect unmarked spoilers ahead.
Anime & Manga
- In Nausicaš of the Valley of the Wind, Kurotawa gets rid of his would-be murderer by sidestepping as he tries to push him into a Bottomless Pit, making a snarky comment on how the rumors of newly-sent officers (like himself) meeting unfortunate ends weren't exaggerated.
- Happens in Blood Simple, when the heroine manages to fight off and kill the Psycho for Hire.
- In Dial M for Murder, Margot Wendice's husband, Tony hires a crook named Swann to strangle her to death. However, Margot manages to stab him to death with her scissors.
- A Perfect Murder, the 1998 remake, has a similar situation, though in this case the wife stabbed her assailant to death with a meat thermometer rather than a pair of scissors.
- Our Man Flint. While Flint is in a restaurant bathroom, Hans Gruber enters and tries to murder him with a gun and a knife. Flint turns the tables on him and stabs him to death with his own knife.
- Non-Stop: When Marks confronts a fellow air marshal he thinks is behind the plot to hijack the flight, the two get into a fight in the plane's lavatory. The other one gets hold of a gun and Marks snaps his neck before he has a chance to use it.
- Pulp Fiction: Vincent Vega is assigned to kill Butch, but happens to take a bathroom break when Butch comes home. Butch finds Vincent's gun lying on the kitchen counter and shoots him.
- This trope turns out to have been in effect at the end of Mademoiselle de Scuderi by E. T. A. Hoffmann.
- Goldfinger opens with James Bond with a glass of whiskey in hand, who is thinking about the Mexican killer whom he was forced to kill in self-defence, and tries to rationalize about it by telling himself that he was very likely a very bad person.
- In American Horror Story: Asylum Lana Winters kills her son, who has been on a killing spree and has avowed vengeance on his mother for killing his father, the original bloody face (because he was also trying to kill her).
- Babylon 5: The episode "The Quality of Mercy" has a Back-Alley Doctor who uses an alien device to transfer her life energy to her patients. At the end, an escaped killer takes her and her daughter hostage, demanding he heal a wound he got from security, but she eventually realizes he intends to kill them both anyway and reverses the flow, killing him and curing herself (apparently the actual purpose of the device: executing criminals in a painless way while using the execution to save someone terminally ill). The courts decide that she acted in self-defense and drop any charges, on condition she turn the device over to station personnel.
- Boardwalk Empire has a few examples of this:
- Jimmy Darmody murders two thugs who were trying to mug him, an act which actually ends up having consequences for fellow mobsters Meyer Lanski and Lucky Luciano.
- Manny Coachen murders a hitman sent at him by way of a meat cleaver to the head.
- Bones: a suspect in the Victim of the Week's murder (who was cleared when they found who did it) becomes a Stalker with a Crush on Booth, and decides to kill Brennan in order for Booth & her to be together. Booth jumps in front of the bullet, taking it in the shoulder; when the stalker woman raises her gun for another shot Brennan picks up Booth's gun and shoots her in the heart.
- Twice in CSI: NY with Stella, then Jo. Stella had to kill her angry ex-boyfriend and Jo wax attacked by the rapist whose case got her fired in DC.
- The opening scene of Justified shows US Marshall Raylan Givens kill a Miami gun thug in a restaurant. The criminal drew his gun first so the killing is deemed to be justified self defense. However, word spreads around that Raylan has previously give the gun thug 24 hours to leave town "or else". This causes doubts about the shooting and Raylan's superiors ship him off to Kentucky. Even Raylan admits that he is not sure if he would still have killed the criminal if the guy did not draw his gun first. Throughout the series Raylan kills more people but it is always in self defense.
- In the Law & Order episode "Hubris", this is how the Smug Snake villain meets his end. After representing himself and seducing a member of the jury to get himself acquitted, he tries to strangle her from behind while she's washing the dishes (his usual MO for dealing with witnesses) - she accidentally stabs him with a knife she was washing.
- In the season 2 finale of Person of Interest the Dirty Cop organization HR tries to set up Detective Joss Carter, one of the heroes, to get killed during a bust. Carter is quicker on the trigger than her would-be assassin, so the HR member on scene improvises, pocketing the assassin's piece to make it look to Internal Affairs like Carter shot and killed an unarmed man.
- Some cases in Ace Attorney feature this:
- The first time it occured in the franchise was in "Turnabout Samurai" ie. 1-3, where it's ultimately revealed that the killing was an act of self-defense. The surviving party does not come off as particularly sympathetic though, since it's revealed that the would-be killer's motive was taking revenge for having been blackmailed into submission for years on end.
- It's invoked in "Reunion, And Turnabout" (ie. 2-2), where the prosecutor tries to push Phoenix into pleading "justified self-defense". Though it's ultimately a moot point seeing as the killing was committed by a different person altogether.
- This was also The Reveal in the second case of Apollo Justice: Ace Attorney. The (relatively) spoiler-free recap being that the victim, Pal Meraktis, strangled the culprit, after which he tried to dump the body into a river. Said culprit was Not Quite Dead, however, and killed him shortly after regaining conciousness.
- It's also invoked in the final case of Ace Attorney Investigations: Miles Edgeworth, where the culprit claims he killed an interloper who was hired to steal something from him in self-defense. It's heavily implied to be a lie and it ultimately becomes a moot point seeing as he killed another person that night in what was not a case of self defense.
- Dangan Ronpa has this for the first murder, where one of the characters attempts to commit a perfect murder on another character in order to escape the school. The attempted victim retaliates, however, and ends up stabbing them to death. Monokuma has none of this argument, though, and executes the surviving party anyway. The manga portrays it as both this trope and an Accidental Murder, the surviving party had been trying to snap their victim (who was still trying to kill them) out of a Freak Out.
- Invoked and played with in early episodes of South Park: hunters Jimbo & Ned justify their hunting by shouting "It's coming right for us!" before shooting in order to claim self defense. This loophole is later closed (but they find another loophole to use).
- The story goes that Edward The First killed a Mamluk assassin with his own blade.
- A man in Portland, Oregon hired a hitman to kill his estranged wife. After a protracted struggle, the woman was able to disarm the hit man and subsequently strangled him to death.