Malicious prosecution

Malicious prosecution is an action instituted with intention of injuring the defendant and without probable cause, and which terminates in favor of the person prosecuted. Other similar terms used include frivolous litigation and vexatious litigation.

In many jurisdictions, such a person (who often files the suit pro se) will be barred from filing suits, unless a licensed attorney files the suit on his/her behalf

An attorney who engages in such actions can be disbarred; this was the case with Fred Phelps (better known as the pastor of the Westboro Baptist Church; after several such actions he agreed to surrender his law license).