Legal Definitions - third-party complaint

A third-party complaint is a legal document filed by a defendant in a civil lawsuit against a third party. The complaint alleges that the third party may be responsible for some or all of the damages that the plaintiff is trying to recover from the defendant.

For example, if a person is injured in a car accident and sues the driver for damages, the driver may file a third-party complaint against the car manufacturer, alleging that a defect in the car caused the accident.

The purpose of a third-party complaint is to bring all parties who may be responsible for the plaintiff's damages into the lawsuit, so that the court can determine who is liable and to what extent.