Bob has made his wife Alice's life a living hell. He beats her, he closely monitors her movements and he effectively prevents her from living a normal life.
As he's about to beat her for the three-hundredth time, Alice suddenly grabs the ashtray and strikes him across the head. Bob dies on the way to the hospital and Alice is arrested for his murder. There is no doubt that she's done it, but wouldn't anyone else do what she did if faced with what she's gone through?
Alice's lawyers decide that Alice denies murder, but will claim manslaughter by provocation. The question is now, will the jury agree?
"Manslaughter by provocation", in English law, requires actual provocation and must pass a test of whether a reasonable, sober, self-controlled person would do it. The other partial defenses are diminished responsibility and suicide pacts.
In the US, it is one of the three partial defenses to murder (the others being diminished and unjustified use of force in what they thought was self-defense).
In both cases, the crime becomes voluntary manslaughter rather than murder, which could still carry prison time, but it's far less than actual murder charges.
It used to be the case that catching your spouse in the act of adultery was considered sufficient provocation for murder (though the ancient Celts had a time limit on that, you were expected to have cooled down three days after the adultery). Generally, most people nowadays agree that you're not allowed to kill someone for that.
- Crazy in Alabama: Lucille poisons her husband after suffering years of hellish domestic abuse, and argues in court that she feared for her life because he spent every day of her marriage trying to crush it out of her. She's still convicted of first-degree murder, but after hearing her testimony about what she suffered, the judge suspends her sentence, puts her on probation, and requires her to seek psychiatric care.
- The Crying Game: This is probably what Fergus gets convicted of.
- In Confessions of a Psycho Cat, Freeman killed the man who was having an affair with his wife: grabbing his cutthroat razor off him and slashing him to death.
- Isaac Asimov's "Light Verse": Lardner, a wealthy socialite who frequently shows off her light-sculptures, also has a household full of robots that she refuses to repair/replace. When Travis, Chief Engineer from US Robotics, is invited to one of her parties, they repair Max without her permission. Upon telling Lardner this, she explodes in anger, telling them that Max's "damage" allowed him to create the widely-acclaimed artworks and now they can never get that talent back. It's noted that Travis may have leapt into the weapon, as they are just as devastated at hearing about the loss to art as Lardner is.
- This is exactly what Billy Budd did, but it was still handled as murder. The victim only got what he deserved... This is because the incident occurred on board a Navy ship on the high seas. If it had happened on land in a civilian situation, it probably would have been Manslaughter by Provocation.
- The Mental State: This is the crime that sends the main character to prison. He snaps after being made to watch is his girlfriend is raped by street thugs. He responds by lacerating, injuring and traumatizing the ones responsible. Although he chose to leave most of them alive so that they could continue to suffer, he killed one of them on account of him suffering from psychosis and, therefore, physically incapable of ever truly reforming.
- The entire plot of Criminal Justice 2, a five-part 2009 BBC mini-series starring Maxine Peake, who kills her abusive husband with a knife. She'd brought the knife to bed planning to kill herself when her husband raped her again but turned the knife on him. The jury goes for manslaughter provocation. The judge gives her five years, though, enough for her to lose the baby she conceived with another man.
- A Law & Order: UK episode involves a mother killing the man who was responsible for the death of her daughter in a botched kidnapping as he leaves his bail hearing. The CPS has to go for murder as the charge. The jury convicts on manslaughter provocation and she gets a suspended sentence. She was in on the original kidnapping and they convict her on gross negligence manslaughter instead.
- This premise was originally used in the American Law & Order.
- Nikki Wade of Bad Girls is a prison lifer for killing a police officer who was trying to rape her partner.
- Waterloo Road, where a pupil kills her sexually abusive father, although it's as yet unclear if she'll get a jury to go for manslaughter provocation, as it was pre-meditated.
- Justified: The antagonist's brother is killed by his wife who blows his head off with a shotgun at the dinner table. It is implied that she will plead to manslaughter. Nobody in the town seems to have a problem with what she did since the husband was an abusive drunk who beat her constantly. Even the antagonist considers her actions justified and seems more concerned with the fact that she is now single. This kind of thing appears to be a central theme of the show.
- A Criminal Minds episode features a B-plot where Rossi and Hotch are asked to consult on a case by a skeptical prosecutor dealing with a woman who murdered her husband and claims it was this. The reason the prosecutor is skeptical is that the woman has no bruise marks, broken bones or any other signs of physical injuries, the husband was well-liked and respected by those who knew him, and even her children say she is lying and paint her as a terrible parent. Hotch and Rossie eventually conclude that she was telling the truth and that the husband was a Villain with Good Publicity who was actually a psychologically abusive Control Freak who had brainwashed their children into hating their mother and think she was useless. It's eventually revealed that the husband was so absolutely controlling that after stabbing him to death in their bedroom, the wife immediately tidied everything up, cleared up all the blood and made sure everything was perfectly clean because she knew he would be mad at her for the mess she made.
- An episode of Stargate SG-1 plays with the trope. When Teal'c gets an apartment off-base, he helps his next-door neighbor deal with her abusive boyfriend, including teaching her some self-defense techniques. This ends in her "crushing the man's windpipe" during a struggle, and she panics and runs away, prompting the police to look into it as a homicide. By the end of the episode, however, Teal'c manages to obtain what we're told is iron-clad evidence that the killing was in self-defense, and the girl is acquitted.
- On Hell on Wheels the people running the lawless town of Cheyenne consider cheating at cards sufficient provocation to justify someone getting shot. However, one such incident occurs on the day the new governor arrives together with a new judge and US Marshal. A trial is held and the judge quickly disallows this defense. The shooter tries to instead claim self-defense but the judge, the US Marshal, and two deputies were witnesses to the murder so this does not fly and the killer is promptly hanged.
- Daredevil (2015): Wilson Fisk's father Bill beats his wife Marlene with a belt repeatedly, until Wilson snaps and beats him to death with a hammer. Afterwards, Fisk and his mother cut the body up with a chainsaw and dispose of it, with it being implied to both be 1) so the mob won't retaliate against them (since Bill owed a lot of money to them) and 2) because the legal system likely would not be on the side of a working class Hell's Kitchen resident like Fisk.
- The F.B.I.: In "A Mouthful of Dust", Joe Cloud comes home unexpectedly and finds a man attacking his wife. In a fit of blind rage, he chokes her attacker to death.
- A semi-obscure Country Music song by Kenny Rogers, "Harder Cards," deals with the moral dilemma of a police officer called to a scene virtually identical to the one outlined in the Trope description above. The police officer is portrayed as sympathetic, if not in the right, for helping the woman cover up her crime.
- Although played for laughs and subverted, the ladies of Chicago plead this in "The Cell Block Tango". Given their contrasting explanations and lines such as being driven by gum chewed too loudly nobody buys is.
- Silent Hill 2 has two examples:
- Angela Oscoro killed her father after nearly twenty years of sexual abuse. The effects of her father's abuse have left her unable to be anywhere near others without having a mental breakdown; this can be seen when James attempts to help her and she shrieks at him and runs away instead.
- In a far less sympathetic example, Eddie Dombroski kills five or six people (and one dog) because they made fun of him for being overweight.
- Although from how he talks of it, he just went nuts and killed a dog and shot its owner once before running away.
- Leon Kuwata from Danganronpa: Trigger Happy Havoc. It turns out that Sayaka lured him into Makoto's room and attempted to kill him, but locked herself in the bathroom after he managed to overpower her and break her wrist. He then went to his room to collect his toolbox so he could break into the bathroom. What happened next depends on the adaptation; in the original game, Maizono lost the knife and Leon killed her in cold blood. In the manga, Maizono still had the knife, and Leon was making a poorly-thought out attempt to calm her down; she was accidentally stabbed in the struggle, subverting the trope.
- Teruteru Hanamura from Danganronpa 2: Goodbye Despair tries to claim this because he knew that Nagito was planning murder. However, the other students immediately point out that Byakuya's death could have been prevented if he had told anyone else when he found out and worked with everyone to neutralize Nagito in a non-lethal manner.