An
affirmative defense is a category of
defense used in
litigation between private parties in
common law jurisdictions, or, more familiarly, a type of defense raised in
criminal law by the
defendant. Affirmative defenses can be classified as either a justification defense or an excuse defense. Affirmative defenses operate to limit, excuse or avoid a defendant's criminal
culpability or civil
liability, even though the factual allegations of the
plaintiff's
claim are admitted or proven. In fact, the defendant usually must affirm that the facts asserted by the plaintiff are correct in asserting his own defense; hence, "affirmative" defenses.
A clear illustration of an affirmative defense is
self-defense. In its simplest form, a criminal defendant may be exonerated if he can demonstrate that he had an
honest and
reasonable belief that his conduct was necessary to protect himself from another's use of unlawful force.
"Mistake of fact" is another affirmative defense, usually used in combination with another, in which the defendant asserts that he reasonably believed the culpable act was necessary based on his observation, although, when given complete knowledge of the situation, it is clear that the act was unwarranted. Self-defense is still valid even if the defendant mistakenly believed he was in imminent danger of harmful or offensive bodily contact.
Among the most controversial affirmative defenses is the
insanity defense, whereby a criminal defendant, shown to be insane at the time of his crime, seeks commitment to a mental institution in lieu of imprisonment.
Most affirmative defenses must be timely pled by a defendant in order for the court to consider them, or else they are considered waived by the defendant's failure to assert them. The classic unwaivable affirmative defense is lack of
subject-matter jurisdiction. What constitutes timely assertion is often itself the subject of contentious litigation.
Because an affirmative defense requires an assertion of facts beyond those claimed by the plaintiff, generally the party making an affirmative defense bears the
burden of proof. The burden of proof is typically lower than
beyond a reasonable doubt. It can either be proof by
clear and convincing evidence or a
preponderance of the evidence. In some cases or jurisdictions, however, the defense must only be asserted, and the prosecution has the burden of proving beyond a reasonable doubt that the defense is not applicable.
Rule 8 of the
Federal Rules of Civil Procedure governs the assertion of affirmative defenses in civil cases filed in the
United States district courts. Rule 8(c) specifically enumerates the following defenses: "
accord and satisfaction,
arbitration and award,
assumption of risk,
contributory negligence,
discharge in bankruptcy,
duress,
estoppel, failure of
consideration,
fraud,
illegality, injury by
fellow servant,
laches,
license,
payment,
release,
res judicata,
statute of frauds,
statute of limitations,
waiver, and any other matter constituting an avoidance or affirmative defense."
An affirmative defense is different from a negating defense. A negating defense is one which tends to negate an essential element of the state's case. Examples include voluntary intoxication and diminished capacity. The defendant does not have any burden of persuasion with regards to a negating defense. At most the defendant has the burden of producting sufficient evidence to raise the issue.
Examples
- * contractual provision (when the defendant's liability for causing the plaintiff's injuries had been waived in the contract)
- * laches (similar to statute of limitations)
See also