AFFIRMATIVE DEFENSE

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 operate to limit or excuse or avoid a defendant's criminal culpability or civil liability, even if the factual allegations of plaintiff's claim are admitted or proven.
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new facts or legal defenses in response to the opposing spouse's pleading.