Bogus liens are one of the oldest and most common sovereign citizen "paper terrorism" tactics. They are designed to harass and retaliate against their perceived enemies. Whereas most legitimate liens are placed against property for nonpayment of a debt, a bogus lien is placed against a person's property simply because they have irritated the sovereign citizen who filed the lien. Even if the lien is bogus, it often takes time, effort and expense to get it removed, which is what makes it an effective tactic. A number of states (and the federal government) have passed laws to make removing such liens easier and/or filing them illegal, but the tactic continues.