A peremptory challenge is a right during voir dire (the process of selecting a jury) to reject a certain number of potential jurors without having to give a reason. The word "peremptory" means without a reason given; allowing no contradiction or refusal. Peremptory challenges may be made by either party to the proceedings. This kind of challenge has been more difficult to use because the Supreme Court of the United States has prohibited peremptory challenges (also called peremptory strikes) based on gender or race. Different jurisdictions allow different numbers of peremptory challenges to each side. Some jurisdictions allow additional peremptory challenges. In United States federal courts each side is allowed three peremptory challenges. Also, if there are more than two parties involved in the proceeding the court may allow additional challenges or restrict the number for all parties.