When one or more judges on a panel disagree with the majority's judgment in a court judgement, they can file an official dissenting opinion. In general, a dissident opinion is simply one that disagrees with others, particularly one that contradicts a conventional perspective. A dissenting opinion is most common in cases where there is no clear majority decision that can be adopted by the court. In American law, judges are appointed by the president and then confirmed by the Senate. If a judge votes to decide a case before it is argued in front of the full court, this is known as "casting a ballot" on the case. If another judge votes differently, his or her vote can cause the first judge to change his or her mind and vote in favor of dismissing the appeal. This second judge's vote is called a "dissenting opinion." The term "dissenting opinion" does not appear in the United States Constitution, but rather in a federal statute: The Supreme Court cannot overrule itself. Therefore, if five judges vote to deny an appeal, no matter how well-reasoned the opposing views may be, the lower court ruling stands. The fact that two judges can cause a third to change their mind shows just how powerful a dissenting opinion can be. It demonstrates that even when there is no clear majority rule, two judges can prevent a decision from being made if they can't come to an agreement.