A plaintiff is the person who initiates action in a lawsuit. In a personal injury lawsuit, the injured person will be the person to initiate action. The injured will choose to sue the offender who allegedly caused their injury, making them the plaintiff, and the offender the defendant. As the plaintiff in a civil trial, the injured party also has the burden of proof. This means it is their responsibility to prove that the alleged claims are true, using evidence. In a personal injury lawsuit, like other civil cases, the determination of fault is made based on preponderance of evidence. The plaintiff must use evidence to prove that they are "more correct" by tipping the balance between their evidence and the opposing party's. If there is a greater than 50% chance that their allegations are correct, that is enough for the jury to decide in their favor. A plaintiff is also responsible for mitigation of damages once they discover their injury.