Voluntary Manslaughter: Heat of Passion
A killing that would otherwise be murder can be reduced to voluntary manslaughter if the defendant killed someone because of a sudden quarrel or in the heat of passion. A defendant kills someone because of a sudden quarrel or heat of passion when: the defendant was provoked; as a result of the provocation, the defendant acted rationally and under the influence of intense emotion that obscured his or her reasoning or judgment; and the provocation would've caused a person of average disposition to act rationally and without due deliberation, that is, from passion rather than from judgment.
Heat of passion does not require anger, rage, or any specific emotion. It can be any violent or intense emotion that causes a person to act without due deliberation and reflection. In order for heat of passion to reduce murder to involuntary manslaughter, the defendant must have acted under the direct and immediate influence of provocation. While no specific type of provocation is required, slight or remote provocation is not sufficient. Sufficient provocation may occur over a short or long time.
It is not enough that the defendant simply was provoked. The defendant is not allowed to set up his or her own standard of conduct. The jury must decide whether the defendant was provoked and whether the provocation was sufficient. In deciding whether the provocation was sufficient, the jury must consider whether a person of average disposition, in the same situation and knowing the same facts, would have reacted from passion rather than from judgment.
However, if enough time passes between the provocation and the killing for a person of average disposition to "cool off" and regain his or her clear reasoning and judgment, then the killing is not reduced to voluntary manslaughter.
If a defendant raises the defense of voluntary manslaughter because of a sudden quarrel or in the heat of passion, the government has the burden of proving beyond a reasonable doubt that the defendant did not kill as a result of a sudden quarrel or in the heat of passion.
Voluntary Manslaughter: Imperfect Self-Defense
A killing that would otherwise be murder can be reduced to voluntary manslaughter if the defendant killed a person because he or she acted in imperfect self-defense or in imperfect defense of another. The difference between complete self-defense or defense of another and imperfect self-defense or imperfect defense of another depends on whether the defendant's belief in the need to use deadly force was reasonable.
A defendant acts in imperfect self-defense or imperfect defense of another if: the defendant actually believed that he or she or someone else was in imminent danger of being killed or suffering great bodily injury; and the defendant actually believe that the imminent use of deadly force is necessary to defend against the danger; but at least one of those beliefs were unreasonable.
Belief in future harm is not sufficient, no matter how great or how likely the harm is believed to be. In evaluating the defendant's beliefs, the jury must consider all the circumstances as they were known and appeared to the defendant.
If a defendant raises the defense of voluntary manslaughter based on imperfect self-defense or imperfect defense of another, the government has the burden of proving beyond a reasonable doubt that the defendant was not acting in imperfect self-defense or imperfect defense of another.
When a person commits an unlawful killing but does not intend to kill and does not act with conscious disregard for human life, then the crime is involuntary manslaughter.
The difference between other homicide offenses and involuntary manslaughter depends on whether the person was aware of the risk to life or that his or her actions created a conscious disregard of that risk. An unlawful killing caused by a willful act done with full knowledge and awareness that the person is endangering the life of another, and done in conscious disregard of that risk, is voluntary manslaughter or murder. An unlawful killing resulting from a willful act committed without intent to kill and without conscious disregard of the risk to human life is involuntary manslaughter.
A defendant commits involuntary manslaughter if: the defendant committed a crime or a lawful act in an unlawful manner; the defendant committed the crime or act with criminal negligence; and the defendant's act unlawfully caused the death of another person.
Criminal negligence involves more than ordinary carelessness, inattention, or mistaken judgment. A person acts with criminal negligence when: he or she acts in a reckless way that creates a high risk of death or great bodily injury; and a reasonable person would have known that acting in that way would create such a risk. In other words, a person acts with criminal negligence when the way he or she acts is so different from the way and ordinarily careful person would act in the same situation that his or her act amounts to disregard for human life or indifference to the consequences of that act.