Certiorari is a Latin word meaning "to be informed of, or to be made certain in regard to". It is also the name given to certain appellate proceedings for re-examination of actions of a trial court, or inferior appeals court. The U.S. Supreme Court still uses the term certiorari in the context of appeals.
Petition for Writ of Certiorari. (informally called "Cert Petition.") A document which a losing party files with the Supreme Court asking the Supreme Court to review the decision of a lower court. It includes a list of the parties, a statement of the facts of the case, the legal questions presented for review, and arguments as to why the Court should grant the writ.
Writ of Certiorari. A decision by the Supreme Court to hear an appeal from a lower court.
Cert. Denied. The abbreviation used in legal citations to indicate that the Supreme Court denied a Petition for Writ of Certiorari in the case being cited.
Someone with a legal claim files a lawsuit in a trial court, such as a U.S. District Court, which receives evidence, and decides the facts and law. Someone who is dissatisfied with a legal decision of the trial court can appeal. In the federal system, this appeal usually would be to the U.S. Court of Appeals, which is required to consider and rule on all properly presented appeals. The highest federal court in the U.S. is the Supreme Court. Someone who is dissatisfied with the ruling of the Court of Appeals can request the U.S. Supreme Court to review the decision of the Court of Appeals. This request is named a Petition for Writ of Certiorari. The Supreme Court can refuse to take the case. In fact, the Court receives thousands of "Cert Petitions" per year, and denies all but about one hundred. If the Court accepts the case, it grants a Writ of Certiorari.
"Review on writ of certiorari is not a matter of right, but a judicial discretion. A petition for writ of certiorari will be granted only for compelling reasons." Rule 10, Rules of the U.S. Supreme Court.
The U.S. Supreme Court's certiorari process is covered in Rules 10-16, Rules of the U.S. Supreme Court.
The effect of denial of certiorari by the U.S. Supreme Court is often debated. The decision of the Court of Appeals is unaffected. However, the decision does not necessarily reflect agreement with the decision of the lower court.