A writ of certiorari is a legal order issued by a higher court directing a lower court to send the record of a case for review. It is primarily used to seek judicial review of a lower court's decision, allowing the higher court to examine the case for errors or important legal questions
. In the context of the U.S. Supreme Court, a writ of certiorari is the mechanism by which the Court decides which cases to hear. A party dissatisfied with a lower court ruling files a petition for a writ of certiorari, requesting the Supreme Court to review the case. The Court grants certiorari only if at least four Justices agree to hear the case, a process known as "granting cert." If certiorari is denied, the lower court's decision stands without Supreme Court review
. The Supreme Court typically grants certiorari to cases involving significant national legal questions, conflicts among lower courts, or issues of federal law. The writ orders the lower court to deliver the full case record for the Supreme Court's review. The Court hears only a small fraction of petitions filed annually, focusing on cases with broad legal implications
. In other legal systems, such as Australia, a writ of certiorari is a discretionary remedy used in judicial review to quash decisions made without jurisdiction or legal authority. It removes the official record of the decision and nullifies the decision itself, typically addressing errors of jurisdiction or fundamental legal defects
. In summary, a writ of certiorari is a discretionary judicial tool used by higher courts, especially the U.S. Supreme Court, to review and potentially overturn lower court decisions by examining the case record and legal issues involved
