When must I file a brief opposing certiorari?

Find the date the case was placed on the Supreme Court docket. Do not substitute petition service or lower-court judgment entry.

Read any Court request and the docket’s stated response date. Rule 15.3 allows extension by the Court, a Justice or the Clerk under Rule 30.4.

Determine whether a brief, waiver or particular corporate disclosure is required. An optional response does not make a filed brief exempt from timing and form.

1. Use Supreme Court docketing, then check any Court, Justice or authorized Clerk extension.
2. Exclude the established trigger day.
3. Count 30 calendar days.
4. Apply Rule 30.1 final-day adjustment.
5. Complete the required filing by that date.

Supreme Court Rule 30.1 excludes the trigger day and includes every intermediate calendar day. For periods shorter than seven days it excludes intermediate closed days. Each fixed period reviewed here is at least seven days.

An extension request does not itself establish the new filing date. Use the actual authorized extension and docket direction.

If the final day is Saturday, Sunday, a federal legal holiday listed in 5 U.S.C. 6103 or a Court-building closure ordered by the Court or Chief Justice, Rule 30.1 continues the period to the next day that is none of those. Check actual Court closure orders. The calculator does not infer additional closures.

Fictitious example

Fictitious Supreme Court docketing on August 24, 2026. The respondent files a brief in opposition under the ordinary 30-day schedule, without an extension. Exclude the established trigger day, August 24, 2026. Counting 30 calendar days reaches September 23, 2026. The final day is an open weekday.

Fictitious facts and dates. No different schedule, additional Court closure or extension is assumed.

Mandatory responses

Rule 15.1 makes a brief in opposition mandatory in a capital case or when requested by the Court.

Specified corporate respondent

Rule 15.9 requires a brief or waiver from a nongovernmental corporate respondent with a parent corporation or qualifying ten-percent publicly held corporate ownership. Include Rule 29.6 information.

Copies and format

Rule 15.3 generally requires 40 copies. In-forma-pauperis circumstances have different format and copy requirements. Check the petitioner’s status as well as the respondent’s.

Jurisdiction and issues

Rule 15.4 prohibits a separate respondent motion to dismiss a certiorari petition. Put jurisdictional objections in the opposition. Rule 15.2 addresses misstatements, preservation, parties and related cases.

Distribution is separate

Rule 15.5 describes Clerk distribution and a waivable waiting period following a timely opposition. It does not guarantee an exact consideration date or delay distribution for a reply.

• The calculator counts the encoded default period after an established trigger. It does not determine jurisdiction, party alignment or the effect of a particular order.
• Check the Court’s docket, actual directions and proof of the required act.

• Verify Supreme Court docketing and the actual response direction.
• Determine whether the case, Court request or corporate facts require a response or waiver.
• Check actual extensions under Rule 30.4.
• Include required objections, parties, corporate information and related-case information.
• Check format, copies and any pauper motion, and file and serve the separate opposition.
• Rule 29.2 distinguishes timely paper receipt, qualifying USPS postmark, commercial-carrier delivery and proper electronic submission. Under the March 2026 rule, electronic timeliness requires the paper copies to be delivered or mailed by a specified method within three days. Rule 29.7 and the current guidelines impose additional electronic-submission requirements for represented filers and identify exceptions. Filing with the Court does not itself transmit the document to other parties.
• Check represented-filer electronic requirements and paper-copy requirements. The March 2026 guidelines exempt specified sealed and privacy-sensitive filings from electronic submission.
• Preserve both filing and separate service evidence.