Tennessee Writ of Certiorari is a form of review used in the state of Tennessee Court of Appeals and Supreme Court. It is a discretionary review process by which a higher court can review a decision of a lower court and either affirm or reverse that decision. There are two types of Tennessee Writ of Certiorari: Permissive Certiorari and Mandatory Certiorari. Permissive Certiorari is issued at the court's discretion, and is used to review matters of great public importance or those that involve a unique or complex legal question. Mandatory Certiorari is issued when the court is required to review a decision by law. This type of Writ is mainly used when a lower court has exceeded its jurisdiction or when it has made an error of law.