Right of self-defense in the context of "Self-defense"

The Hammersmith Ghost murder case of 1804 set a legal precedent in the UK regarding self-defence: that someone could be held liable for their actions even if they were the consequence of a mistaken belief.

Near the end of 1803, many people claimed to have seen or even been attacked by a ghost in the Hammersmith area of London, a ghost believed by locals to be the spirit of a suicide victim. On January 3, 1804, a 29-year-old excise officer named Francis Smith, a member of one of the armed patrols set up in the wake of the reports, shot and killed a bricklayer, Thomas Millwood, mistaking the white clothes of Millwood's trade for the shroud of a ghostly apparition. Smith was found guilty of murder and sentenced to death, later commuted to one year's hard labour.

Justification is a defense in a criminal case, by which a defendant who committed the acts asserts that because what they did meets certain legal standards, they are not criminally culpable for the acts which would otherwise be criminal. Justification and excuse are related but different defenses (see Justification and excuse).

Justification is an exception to the prohibition of committing certain offenses. Justification can be a defense in a prosecution for a criminal offense. When an act is justified, a person is not criminally liable even though their act would otherwise constitute an offense. For example, to intentionally commit a homicide would be considered murder. However, it is not considered a crime if committed in self-defense. In addition to self-defense, the other justification defenses are defense of others, defense of property, and necessity.

International law recognizes a right of self-defense according to the Chapter VII, Article 51 of the UN Charter, as the International Court of Justice (ICJ) affirmed in the Nicaragua Case on the use of force. Some commentators believe that the effect of Article 51 is only to preserve this right when an armed attack occurs, and that other acts of self-defence are banned by article 2(4). Another view is that Article 51 acknowledges the previously existing customary international law right and then proceeds to lay down procedures for the specific situation when an armed attack does occur. Under the latter interpretation, the legitimate use of self-defence in situations when an armed attack has not actually occurred is still permitted, as in the Caroline case noted below. Not every act of violence will constitute an armed attack. The ICJ has tried to clarify, in Nicaragua Case, what level of force is necessary to qualify as an armed attack.

Huey Percy Newton (February 17, 1942 – August 22, 1989) was an African American revolutionary and political activist who co-founded the Black Panther Party in 1966. He ran the party as its first leader and crafted its ten-point manifesto with Bobby Seale. Under his leadership, the Party organized numerous social programs and community events, but also advocated for collective defense and threatened political violence.

Newton learned to read using Plato's Republic, which influenced his philosophy of activism. He went on to earn a PhD in social philosophy from the University of California at Santa Cruz's History of Consciousness program in 1980.

Imperfect self-defense is a common law doctrine recognized by some jurisdictions whereby a defendant may mitigate punishment or sentencing imposed for a crime involving the use of deadly force by claiming, as a partial affirmative defense, the honest but unreasonable belief that the actions were necessary to counter an attack. Not all jurisdictions accept imperfect self-defense as a basis to reduce a murder charge.

• Self-defense: A perfect argument of self-defense proves all elements of self-defense, and results in the defendant's acquittal. If a defendant proves imperfect self-defense, the defendant will be convicted of a lesser homicide charge, such as voluntary manslaughter.
• Imperfect self-defense: The concept of imperfect self-defense is that, although not all elements of self-defense were proved, extenuating circumstances nonetheless partially excuse the act that caused death.

An affirmative defense to a civil lawsuit or criminal charge is a fact or set of facts other than those alleged by the plaintiff or prosecutor which, if proven by the defendant, defeats or mitigates the legal consequences of the defendant's otherwise unlawful conduct. In civil lawsuits, affirmative defenses include the statute of limitations, the statute of frauds, waiver, and other affirmative defenses such as, in the United States, those listed in Rule 8 (c) of the Federal Rules of Civil Procedure. In criminal prosecutions, examples of affirmative defenses are self defense, insanity, entrapment and the statute of limitations.