Certiorari, often shortened to “cert,” is a request asking a higher court to review a lower court’s decision. The word comes from Latin for “to be informed,” and in modern American law the meaning of certiorari is tied almost entirely to the U.S. Supreme Court: it is the mechanism by which the Court decides which cases from the federal appeals courts and state high courts it will hear. The Court receives upward of 7,000 petitions each year and grants roughly 1% of them.1Harvard Law Review. The Certiorari Process and State Court Decisions A grant is called a “writ of certiorari,” and a denial leaves the lower court’s ruling in place.
Why the Court Grants Cert
Supreme Court review is not something a losing party is entitled to. Rule 10 of the Court’s own rules states that certiorari “is not a matter of right, but of judicial discretion” and will be granted “only for compelling reasons.”2Legal Information Institute (LII). Rule 10 – Considerations Governing Review on Writ of Certiorari
The single biggest driver of a cert grant is a conflict among lower courts on the same legal question. When two federal circuits reach opposite conclusions about what a statute means, people in different parts of the country end up living under different rules, and the Court steps in to resolve the split. The same logic applies when a state supreme court and a federal appeals court disagree on an important federal question.2Legal Information Institute (LII). Rule 10 – Considerations Governing Review on Writ of Certiorari
The Court also looks for unsettled questions of federal law it has not yet addressed but should, and for lower courts that have strayed so far from accepted procedure that its supervisory power is called for. What it almost never does is grant cert simply because a lower court got the facts wrong or misapplied an otherwise correct legal rule. Rule 10 says so explicitly.2Legal Information Institute (LII). Rule 10 – Considerations Governing Review on Writ of Certiorari
How Petitions Get Screened
With thousands of petitions arriving every term, the justices do not personally read each one from scratch. Since 1972, most justices have participated in a system called the cert pool. Their law clerks divide up the incoming petitions, and each petition is assigned to one clerk who reads it and writes a memo summarizing the case, the lower court’s reasoning, and a recommendation. That memo circulates to all participating justices, and a justice’s own clerk may add a supplemental analysis.
Critics argue that funneling each petition through a single clerk increases the risk of an important issue being overlooked. Supporters counter that clerks handling fewer petitions can examine each one more carefully than under the old system, where every clerk skimmed every filing.
At the justices’ private conference, they vote. The threshold is surprisingly low: only four of the nine justices need to vote yes for certiorari to be granted. This “Rule of Four” has been in place since at least the 1920s, when the justices told Congress that four votes would always be enough to guarantee review. That assurance helped persuade lawmakers to pass the Judiciary Act of 1925, which gave the Court broad discretion over its docket.3Federal Judicial Center. The Supreme Courts Rule of Four
Filing a Cert Petition
Timing is unforgiving. A petitioner has 90 days from the entry of the lower court’s judgment to file with the Supreme Court clerk’s office. The clock runs from the date the judgment is entered, not from the date of notice or the date any mandate issues. If a timely petition for rehearing was filed in the lower court, the 90-day window resets from the date rehearing is denied, or from the date of the new judgment if rehearing is granted.4Legal Information Institute (LII). Rule 13 – Review on Certiorari: Time for Petitioning
Extensions are possible but disfavored. A single justice may grant up to 60 additional days for good cause. The extension application must be filed at least 10 days before the original deadline expires, must explain why the extra time is justified, and must identify the judgment under review and the basis for the Court’s jurisdiction.4Legal Information Institute (LII). Rule 13 – Review on Certiorari: Time for Petitioning
The petition itself is a formal document. It must lay out the questions the petitioner wants the Court to resolve, explain why those questions matter beyond the individual case, describe the lower court’s decision, and cite the statutes and precedents supporting the petitioner’s position. Word limits are strict: 9,000 words including footnotes in the standard booklet format, or 40 pages on 8½-by-11-inch paper.5Legal Information Institute (LII). Rule 33 – Document Preparation: Booklet Format; 8 1/2- by 11-Inch Paper Format
The filing fee is $300.6Legal Information Institute (LII). Rule 38 – Fees Petitioners who cannot afford it can ask to proceed “in forma pauperis” by filing a motion with a notarized affidavit or declaration detailing their financial situation. If the lower court already appointed counsel, the affidavit is not required, but the motion must cite the provision of law under which counsel was appointed.7Legal Information Institute (LII). Rule 39 – Proceedings In Forma Pauperis In forma pauperis petitions make up the bulk of the Court’s incoming filings, though they are granted at a far lower rate than paid petitions.
What Happens After a Grant
When the Court agrees to hear a case, a new round of full merits briefing begins. Both sides file detailed briefs, and oral argument is typically scheduled at least three months after the grant. The justices then deliberate and eventually issue a written opinion, which can take weeks or months.
A common misconception is that granting certiorari automatically freezes the lower court’s decision. It does not. A party wanting the lower ruling paused must separately request a stay. In the federal appeals courts, a motion to stay the mandate must show that the certiorari petition presents a substantial question and that good cause supports the stay. The appeals court can require a bond as a condition, and the stay itself cannot exceed 90 days unless a petition has actually been filed, in which case it continues until the Supreme Court disposes of the case.8Legal Information Institute (LII). Rule 41 – Mandate: Contents; Issuance and Effective Date; Stay The Supreme Court itself can also stay enforcement under 28 U.S.C. § 2101(f), but that requires a majority of five justices.9United States Courts. Supreme Court Procedures
If the Court reverses, it often sends the case back for further proceedings consistent with its opinion. If it affirms, the lower court’s decision stands and gains Supreme Court authority, binding every court in the country going forward.
What a Denial of Certiorari Means
This is where people get tripped up. When the Court denies certiorari, the lower court’s decision stays in place, but the denial says nothing about whether that decision was right or wrong. As Justice Felix Frankfurter put it, a denial of certiorari “has no legal significance whatever bearing on the merits of the claim.” It means the Court chose not to take the case. It does not mean the Court agrees with the lower court’s reasoning, endorses the outcome, or thinks the losing party’s arguments lack merit.
There are many reasons the Court might deny a petition that have nothing to do with the merits. The legal question might not be fully developed yet. There might not be a genuine conflict among lower courts. The case might involve unusual facts that make it a poor vehicle for deciding the broader issue. Or the Court might simply have too many other cases on its plate. Lawyers and commentators sometimes read tea leaves into cert denials, but the Court has repeatedly warned against that practice.
Where the Word Comes From
Certiorari has deep roots. In medieval English law, dating to roughly 1280, it functioned as a royal demand for information, commanding lower courts and officials to send their records to the King’s Bench for review. The Latin phrase in the writ was “certiorari volumus,” meaning “we wish to be informed.” Because the writ derived from the monarch’s authority rather than a litigant’s right, it was classified as a prerogative writ, and granting it was always discretionary. That discretionary character carried into American law.
The modern shape of certiorari in the federal system owes everything to the Judiciary Act of 1925, commonly called the Judges’ Bill. Before that law, the Supreme Court was obligated to hear a large number of appeals as a matter of right, which overwhelmed its docket. The 1925 Act repealed most of that mandatory jurisdiction and replaced it with discretionary certiorari review.10Federal Judicial Center. Landmark Legislation: The Judges Bill That shift transformed the Supreme Court from an institution that had to take most appeals into the highly selective one it is today, where each granted case carries outsized weight in shaping American law.