Actual controversy

The Supreme Court of the United States has interpreted the Case or Controversy Clause of Article III of the United States Constitution (found in Art. III, Section 2, Clause 1) as embodying two distinct limitations on exercise of judicial review.

First, the Court has held that the clause identifies the scope of matters which a federal court can and cannot consider as a case (i.e., it distinguishes between lawsuits within and beyond the institutional competence of the federal judiciary), and limits federal judicial power only to such lawsuits as the court is competent to hear.

For example, the Court has determined that this clause prohibits the issuance of advisory opinions (in which no actual issue exists but an opinion is sought), and claims where the appellant stands to gain only in a generalized sense (i.e. no more or less than people at large), and allows only the adjudication of claims where (1) the plaintiff has actually and personally suffered injury or harm "in fact", (2) the injury or harm suffered by the plaintiff is fairly traceable to the defendant's actions and (3) the injury or harm would be capable of redress by the court.

Note that as with all parts of the law, there are exceptions. One of the most significant deals with free speech and free expression cases involving the First Amendment where a party suing over a restriction on freedom of speech issues can argue the unconstitutionalty of a statute restricting certain types of speech or expression, even where the restriction might not directly affect them, such as a bookseller or video game dealer may argue that a restriction on some media restricts their customer's ability to choose various works and the restrictions could have a "chilling effect" on some publishers who might not release some works that would be affected by the law. Other than this, generally, there are usually no exceptions to the standing issue at the Federal level.

Secondly, the Court has interpreted the clause as limiting Congress' ability to confer jurisdiction on federal courts. It does so by establishing an outer limit of the types of matters within which Congress may constitutionally confer jurisdiction. Historically, the Court has not interpreted this Clause to limit Congressional power to restrict the jurisdiction of the federal courts.

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