Voluntary manslaughter occurs either when the defendant kills with malice aforethought (intention to kill or cause serious harm), but there are mitigating circumstances which reduce culpability, or when the defendant kills only with an intent to cause serious bodily harm. Voluntary manslaughter in some jurisdictions is a lesser included offense of murder. The traditional mitigating factor was provocation; however, others have been added in various jurisdictions.
[edit]Laws in the United States
There have been many types of voluntary manslaughter. These have not been differentiated here as they are so closely related or indistinguishable that many US jurisdictions do not differentiate between them.[2] The following are some examples of defenses which may be raised to mitigate murder to voluntary manslaughter:
Provocation: A killing which occurs after provocation by an event which would cause a reasonable person to lose self-control. There must not be a cooling off period negating provocation. If there is an interval between the provocation and killing sufficient to allow the passion of a reasonable person to cool, the homicide is not manslaughter, but murder.
Imperfect self-defense: Allowed only in a limited number of jurisdictions in the United States, self-defense is a complete defense to murder.[clarification needed (see talk page)] However, a person who acted in self defense with an honest but unreasonable belief that deadly force was necessary to do so could still be convicted of voluntary manslaughter or deliberate homicide committed without criminal malice. Malice is found if a person killed intentionally and without legal excuse or mitigation.
Diminished capacity is a defense which serves to negate the mental state of "malice". If a jurisdiction recognizes that a person can kill without justification, but also without any evil intent, for example due to a mental defect or mental illness, that jurisdiction is free to define the crime as something less than murder. This partial defense is only available in some US jurisdictions and not others; whereas the complete defense of insanity is available throughout the US, but rarely used because it is more difficult to show.