In civil proceedings and criminal prosecutions under the common law, a defendant may raise a defense (or defence) in an attempt to avoid criminal or civil liability. Besides contesting the accuracy of any allegation made against him or her in a criminal or civil proceeding, a defendant may also make allegations against the prosecutor or plaintiff or raise a defense, arguing that, even if the allegations against the defendant are true, the defendant is nevertheless not liable.
Since a defense is raised by the defendant in a direct attempt to avoid what would otherwise result in liability, the defendant typically holds the burden of proof. For example, if a defendant in an assault and battery case attempts to claim provocation, the victim of said assault and battery would not have to prove that he did not provoke the defendant; the defendant would have to prove that the plaintiff did.
Civil law defenses
In common law, a defendant may raise any of the numerous defenses to limit or avoid liability. These include: