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Note: Varies by jurisdiction
Note: Varies by jurisdiction
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The concept of justifiable homicide in criminal law stands on the dividing line between an excuse, justification and an exculpation. In certain circumstances, homicide is justified when it prevents greater harm to innocents. A homicide can only be justified if there is sufficient evidence to prove that it was reasonable to believe that the offending party posed an imminent threat to the life or well-being of another. To rule a justifiable homicide, one must objectively prove to a trier of fact, beyond all reasonable doubt, that the suspect intended to commit violence. A homicide in this instance is blameless, and  distinct from the less stringent criteria authorizing deadly force in stand your ground rulings.
Societies have investigated and punished acts of murder very differently over the development of criminal law. The Laws of Solon, in early Athenian law, stated that if an accused pled that he was justified in killing another, his case would be tried in a dedicated court called the Delphinion where, for example, it was considered justifiable homicide to kill an adulterer or burglar caught in the act. In eighteenth century English law, it was considered a justifiable homicide if a husband killed a man "ravishing" his wife (Blackstone, Wm. at p391).
In deciding when intentional killings should be treated as justifiable, lawmakers are balancing multiple interests. On the one hand, states usually allow citizens to protect themselves from harm. In modern times, this reflects a social contract where allegiance is rewarded by the provision of policing and other civil defense systems, and the apparatus of redress is a court system. In the United Nations Universal Declaration of Human Rights, Article 3 states that everyone has the right to life, liberty and security of person, and many nations' policy allows for some degree of leniency for "self-defense". In most cases where "self-defense" is substantiated through the legal system, reduced charges (i.e. felony reduced to misdemeanor), reduced prison sentences, or acquittal are the common rulings.
Justifiable homicide is a legal gray area, and there is no clear legal standard for a homicide to be considered justifiable. The circumstances under which homicide is justified are usually considered to be that the defendant had no alternative method of self-defense or defense of another than to kill the attacker.
Common excusing conditions
Potentially excusing conditions common to most jurisdictions include the following.
- Where a state is engaged in a war with a legitimate casus belli, a soldier from one of the combatant states may lawfully kill a soldier in the army of the opposing state so long as that soldier has not surrendered. This principle is embedded in public international law and has been respected by most states around the world. Thus, if there is no formal declaration of war or the casus belli is not legitimate, all those who engage in the fighting and kill combatants could theoretically be prosecuted. Protecting the national interest against external aggressors is considered an excuse on utilitarian grounds, i.e. the greatest public good will be derived from the defeat of the enemy.
- Where a state operates a system of capital punishment, all those who may be involved in the execution are excused from liability. This usually includes the judge who passes sentence, the prison guards who deliver the condemned person to the place of execution, and those who carry out the sentence.
- Many countries agree that it is lawful for a citizen to repel violence with violence to protect his or her own or another's life and limb, or to prevent sexual assault. However, there is less agreement on the extent to which it is justifiable to kill the attacker, as opposed to disarm or disable. The degree of response to the degree of threat may be tested. If the level of force used in defense matches the force threatened and the "winner" of the conflict first retreated or showed a clear intention not to fight (assuming this was possible in the time available), the killer may be exculpated.
- Some countries agree that it is lawful for a citizen to resort to violence to protect valuable property, usually defined as one's home.
- The "heat of the moment" defense: death results from a situation where the defendant is deemed to have lost control. This is often considered a part of the defense of provocation against a charge of murder. Based on the idea that all individuals may suddenly and unexpectedly lose control when words are spoken or events occur, jurisdictions differ on whether this should be allowed to excuse liability or merely mitigate to a lesser offense such as manslaughter, and under which circumstances this defense can be used.
- The doctrine of necessity allows, for example, a surgeon to separate conjoined twins, killing the weaker twin to save the other.
- In the United States, the 2005 Unborn Victims of Violence Act changed the legal definition of human fetuses to "unborn children", formally defining feticide as murder (under USC §1111). However, the law retained explicit exceptions which prohibit the prosecution "of any person for conduct relating to an abortion," "of any person for any medical treatment," or "of any woman with respect to her unborn child," thereby preserving the abortion rights in the United States allowed under Roe v. Wade.
- Several countries, such as the Netherlands, Belgium, Switzerland, Japan, and the US states of Oregon and Washington allow both active and passive euthanasia by law, if justified.
- There is a strand of authority that permits police or other law enforcement officers to use force to protect others from harm. This is another example of utilitarianism: it may be necessary to prejudge the few to benefit the many. But, in many states, there is a presumption of innocence before the criminal case comes to trial.
Example of justified homicide law for police in South Africa
In South Africa, §49 Criminal Procedure Act used to provide:
- (2) Where the person concerned is to be arrested for an offense referred to in Schedule 1 or is to be arrested on the ground of having committed such an offense, and the person authorized under this Act to arrest or to assist in arresting him cannot arrest him or prevent him from fleeing by other means than killing him, the killing shall be deemed to be justifiable homicide.
- This has now been amended by §7 Judicial Matters Second Amendment Act 122 of 1998:
- (2) If any arrestor attempts to arrest a suspect and the suspect resists the attempt, or flees, or resists the attempt and flees, when it is clear that an attempt to arrest him or her is being made, and the suspect cannot be arrested without the use of force, the arrestor may, in order to effect the arrest, use such force as may be reasonably necessary and proportional in the circumstances to overcome resistance or to prevent the suspect from fleeing: Provided that the arrestor is justified in terms of this section in using deadly force that is intended or is likely to cause death or grievous bodily harm to a suspect, only if he or she believes on reasonable grounds-
- (a) that the force is immediately necessary for the purpose of protecting the arrestor, any person lawfully assisting the arrestor or any other person from imminent or future death or grievous bodily harm;
- (b) that there is a substantial risk that the suspect will cause imminent or future death or grievous bodily harm if the arrest is delayed; or
- (c) that the offence for which the arrest is sought is in progress and is of a forcible and serious nature and involves the use of life threatening violence or a strong likelihood that it will cause grievous bodily harm.
Examples of justifiable homicide laws in the United States
A non-criminal homicide ruling, usually committed in self-defense or in defense of another, exists under United States law. A homicide may be considered justified if it is done to prevent a very serious crime, such as rape, armed robbery, manslaughter or murder. The assailant's intent to commit a serious crime must be clear at the time. A homicide performed out of vengeance, or retribution for action in the past, would not be considered justifiable.
In many states, given a case of self-defense, the defendant is expected to obey a duty to retreat if it is possible to do so. In the states of Alabama, Alaska, Arizona, California, Colorado, Connecticut, Florida, Georgia, Hawaii, Indiana, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Mississippi, Missouri, Montana, New Jersey, North Carolina, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, Tennessee, Texas, West Virginia, Washington, Wyoming and other Castle Doctrine states, there is no duty to retreat in certain situations (depending on the state, this may apply to one's home, business, or vehicle, or to any public place where a person is lawfully present). Preemptive self-defense, in which one kills another on suspicion that the victim might eventually become dangerous, is considered criminal.
In the U.S. Supreme Court ruling of District of Columbia v. Heller, the majority held that the Constitution protected the right to the possession of firearms for the purpose of self-defense "and to use that arm for traditionally lawful purposes, such as self-defense within the home".[dead link]
Two other forms of justifiable homicide are unique to the prison system: the death penalty and preventing prisoners from escaping. To quote the California State Penal Code (state law) that covers justifiable homicide:
- 196. Homicide is justifiable when committed by public officers and those acting by their command in their aid and assistance, either--
- 1. In obedience to any judgment of a competent Court; or,
- 2. When necessarily committed in overcoming actual resistance to the execution of some legal process, or in the discharge of any other legal duty; or,
- 3. When necessarily committed in retaking felons who have been rescued or have escaped, or when necessarily committed in arresting persons charged with felony, and who are fleeing from justice or resisting such arrest.
Although the above text is from Californian law, most jurisdictions have similar laws to prevent escapees from custody.