Here's the legal definition for ya:
Qui Tam Action
(kwee tam) n. Latin meaning "who as well," Lawsuit brought by a private citizen (a whistle blower) against someone or a company who is considered to have violated the law when performing a contract with the government or violated a government regulation when a statute exists to provide remedies for such violations. Quit tam suits are brought for "the government as well as the plaintiff." In such actions, the plaintiff is entitled to a percentage of the penalties recovered (which may include large amounts for breach of contract) as a reward for recovering funds for the government by exposing the wrongdoing. The federal or state government will get involved and become a party to the suit, being part of any negotiations and conduct of the case in order to guarantee success. This type of action generally involves significant violates that involve criminal or fraudulent acts, not necessarily technical violations and/or errors.
So how would this apply to Terri?