The case or controversy clause of Article III of the United States Constitution has been deemed to impose a requirement that United States federal courts are not permitted to hear cases that do not pose an actual controversy - that is, an actual dispute between adverse parties which is capable of being resolved by the court. This requirement prohibits courts from issuing advisory opinions, or from hearing cases that are either unripe, meaning that the controversy has not arisen yet or moot, meaning that the controversy has already been resolved. Article Three of the United States Constitution establishes the judicial branch of the federal (national) government. ... The United States federal courts are the system of courts organized under the Constitution and laws of the federal government of the United States. ... A court is an official, public forum which a public power establishes by lawful authority to adjudicate disputes, and to dispense civil, labour, administrative and criminal justice under the law. ... An advisory opinion, in civil procedure, is an opinion issued by a court that does not have the effect of resolving a specific legal case, but merely advises on the constitutionality or interpretation of a law. ... In law, ripeness refers to the readiness of a case for litigation; for example, if a law of ambiguous quality has been enacted but never applied, a case challenging that law lacks the ripeness necessary for a decision. ... In law, a matter is moot if further legal proceedings with regard to it can have no effect, or events have placed it beyond the reach of the law. ...

The earliest expression by the United States Supreme Court of adherence to this requirement came during the presidency of George Washington. Washington sent a letter to the Court asking for their approval should he choose to seek advice from them from time to time on matters that might not come before the Court in a timely manner. Chief Justice John Jay wrote in his response that, although the members of the Court had great confidence in the ability of the president to receive appropriate advice from his executive officers, the Court itself was constitutionally bound not to go beyond its role as an arbiter of judicial questions. The Supreme Court Building, Washington, D.C. The Supreme Court Building, Washington, D.C., (large image) The Supreme Court of the United States, located in Washington, D.C., is the highest court (see supreme court) in the United States; that is, it has ultimate judicial authority within the United States... For the pop band, see Presidents of the United States of America. ... This article is about George Washingtons general life. ... John Jay, first Chief Justice of the United States Oil painting by Gilbert Stuart, 1794 John Jay (December 12, 1745 – May 17, 1829) was an American politician, statesman, revolutionary, diplomat and jurist. ...

The most famous case setting forth the parameters of this requirement is Muskrat v. United States, 219 U.S. 346 (1911), in which the Court held that when Congress paid the legal bills for both the plaintiffs and the defendant (in this case the U.S. Treasury department, by designation), then there was no real controversy between the parties, and a judgment of the Court would be the equivalent of an advisory opinion. Holding Article III of the Constitution limits the jurisdiction of the Court to actual controversies between adverse parties; there is no controversy or adversity where an interested party colludes with a disinterested party to bring the suit solely for the purpose of determining the constitutionality of a particular act of... Court citation is a standard system used in common law countries such as the United States, United Kingdom, and Canada to uniquely identify the location of past court cases in special series of books called reporters. ... 1911 is a common year starting on Sunday (click on link for calendar). ... A plaintiff, also known as a claimant, or a complainant is the party who initiates a lawsuit (also known as an action) before a court. ... In Common law, a defendant is any person who is required to answer the complaint of a plaintiff in a civil suit or any person who has been named in a criminal information or criminal complaint and stands accused of violating a criminal statute. ... The United States Department of the Treasury is a Cabinet department, a treasury, of the United States government established by an Act of U.S. Congress in 1789 to manage the revenue of the United States government. ...