Ordinarily, when you file a lawsuit, you are the plaintiff, but a qui tam lawsuit is different.
When you file a qui tam lawsuit, you file on behalf of the government against a contractor whom you believe to have committed fraud. As a result, your role in the lawsuit is a little bit different, as demonstrated by this explanation of the parties to a qui tam lawsuit.
The defendant is an entity, whether an individual or a larger organization, that you allege to be liable for a violation of civil law. In the case of a qui tam lawsuit, the law in question is the False Claims Act, which dates back to the 1860s to prevent contractors from providing defective products and equipment to the Union Army during the Civil War. Today, the False Claims Act can apply to health care fraud and grant procurement fraud in addition to contractor fraud and attempts to defraud the military.
Even if you bring a qui tam lawsuit, you are not the plaintiff. The plaintiff is the allegedly wronged party, which in this case is the government, which therefore collects the majority of the damages if the court decides the case in the plaintiff’s favor.
According to Reuters, your role in bringing a qui tam lawsuit on the government’s behalf is that of a relator. In other words, you are the one who relates the case to the court and reports potential wrongdoing by filing.
Fraud against the government has the potential to negatively affect the public as well. If you perceive a possible wrong by a federal contractor, a qui tam lawsuit gives you the chance to help make it right. You can receive a portion of the damages awarded to the government, up to 25%.