Malicious prosecution is the tort of causing someone to be prosecuted for a criminal act, knowing that there was no probable cause to believe that the plaintiff committed the crime. The plaintiff must show that the defendant acted with malice or with some purpose other than bringing the guilty to justice. A mere complaint to the authorities is insufficient to establish the tort, but any official proceeding will support the claim—for example, a warrant for the plaintiff’s arrest. The criminal proceeding must terminate in the plaintiff’s favor in order for his suit to be sustained.
A majority of US courts, though by no means all, permit a suit for wrongful civil proceedings. Civil litigation is usually costly and burdensome, and one who forces another to defend himself against baseless accusations should not be permitted to saddle the one he sues with the costs of defense. However, because, as a matter of public policy, litigation is favored as the means by which legal rights can be vindicated—indeed, the Supreme Court has even ruled that individuals have a constitutional right to litigate—the plaintiff must meet a heavy burden in proving his case. The mere dismissal of the original lawsuit against the plaintiff is not sufficient proof that the suit was unwarranted. The plaintiff in a suit for wrongful civil proceedings must show that the defendant (who was the plaintiff in the original suit) filed the action for an improper purpose and had no reasonable belief that his cause was legally or factually well grounded.