Furor brevis

Provocation is a set of events that might be adequate to cause a reasonable person to lose self control, whereby a criminal act is less morally culpable than a premeditated act done out of pure malice (malice aforethought). It "affects the quality of the actor's state of mind as an indicator of moral blameworthiness". The provocation is said to "mitigate" the crime, and the crime is said to be committed in the heat of passion, under an irresistible urge incited by the provoking events, and without being entirely determined by reason. "'Malice aforethought' implies a mind under the sway of reason, whereas 'passion' whilst it does not imply a dethronement of reason, is the furor brevis, which renders a man deaf to the voice of reason so that, although the act was intentional to death, it was not the result of malignity of heart, but imputable to human infirmity. Passion and malice are, therefore, inconsistent motive powers, and hence an act which proceeds from the one, cannot also proceed from the other." Establishing Provocation can reduce a murder charge to a voluntary manslaughter charge.

Provocation may be defined by statutory law, by common law, or some combination. It is a possible defense for the person provoked, or a possible offense by the person provoking. Provocation may be a defense by excuse or exculpation alleging a sudden or temporary loss of control (a permanent loss of control is in the realm of insanity) as a response to another's provocative conduct sufficient to justify an acquittal, a mitigated sentence or a conviction for a lesser charge. Provocation can be a relevant factor in a court's assessment of a defendant's mens rea, intention, or state of mind, at the time of an act of which the defendant is accused.

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