Editorial Pillar / Civil Discovery

Interrogatories: What They Are, How FRCP 33 Limits Them, and How to Answer

Direct Answer

Interrogatories are written discovery questions one party serves on another in a civil lawsuit. The responding party must answer in writing, under oath, within thirty days of service under Federal Rule of Civil Procedure 33(b)(2). Each side is capped at twenty-five interrogatories (including discrete subparts) under Rule 33(a)(1), and the scope is tied to Rule 26(b)(1): relevant to a claim or defense, proportional to the needs of the case, not privileged. Late or evasive answers expose the responding party to a Rule 37 motion to compel and fee-shifting sanctions.

Reviewed by Alexandra Chen-Park, Esq., Employment, Restrictive Covenants & Civil Litigation CounselBar admissions: California, New York, Illinois
Procedural timeline for interrogatories: serve, thirty-day clock, answer or object, meet and confer, motion to compel, sanctions, and Rule 26 supplementation
Rule-anchored
FRCP 33, FRCP 26(b)(1), FRCP 37, CCP 2030.030, CPLR 3130
Attorney reviewed
Alexandra Chen-Park, Esq., Employment, Restrictive Covenants & Civil Litigation Counsel
Four discovery tools
Interrogatories, depositions, document requests, RFAs
Five drafting defects
Compound questions, vague terms, privilege traps, more
Disambiguation

How Interrogatories Differ From Depositions, Document Requests, and Requests for Admission

Federal civil practice offers four written-discovery instruments under the Federal Rules of Civil Procedure. They share the same scope under Rule 26(b)(1) (relevant, proportional, not privileged) but each has its own mechanics, cap, and use case. A balanced discovery plan layers all four; substituting one for another is one of the most common drafting mistakes a pro se litigant makes.

Interrogatories are the cheapest tool to send and the most expensive tool to answer, because the response is drafted by counsel, reviewed by the party, and signed under oath. The other three tools push the cost the other way.

Authority: see Cornell LII on Federal Rule of Civil Procedure 33.

Four civil discovery tools compared side-by-side: interrogatories, depositions, document requests, and requests for admission

Interrogatories

FRCP 33
Answer type
Written, under oath, signed by the party
Cap
25 questions per side (including discrete subparts)
Deadline
30 days from service
Best for
Locking a party into a written, sworn position on a specific fact or contention.

Depositions

FRCP 30
Answer type
Live oral testimony, transcribed by a court reporter
Cap
Seven hours per deponent (Rule 30(d)(1))
Deadline
Scheduled by notice and agreement
Best for
Probing credibility, taking follow-up, and locking in a witness on the record.

Document Requests

FRCP 34
Answer type
Production of documents and electronically stored information
Cap
No numerical cap by default, proportionality applies
Deadline
30 days from service
Best for
Pulling underlying contracts, emails, ESI, and other documents in a party's custody.

Requests for Admission

FRCP 36
Answer type
Admit or deny each statement
Cap
No numerical cap by default rule
Deadline
30 days from service or deemed admitted
Best for
Stripping uncontested facts out of the trial record before pretrial.
Federal Framework

The Federal Rule 33 Framework: Limits, Scope, and the 30-Day Clock

Federal Rule of Civil Procedure 33 governs interrogatories in every federal civil case and supplies the template that most state-court rules copy. Five pieces of the rule do the bulk of the work in practice.

State analogues vary. California Code of Civil Procedure section 2030.030 caps form interrogatories at thirty-five and special interrogatories at thirty-five. New York CPLR 3130 limits parties to one set absent leave. Illinois Supreme Court Rule 213 supplies a thirty-question default cap with a twenty-eight-day response window.

FRCP 33 framework in five pieces: twenty-five question cap, thirty-day clock, scope tied to Rule 26(b)(1), business records option, and objection menu
  1. 1

    25-question cap

    Federal Rule 33(a)(1) caps each side at twenty-five interrogatories, including all discrete subparts. More than that requires leave of court or a written stipulation between the parties.

  2. 2

    30-day response clock

    Rule 33(b)(2) gives the responding party thirty days from service to answer or object. A missed clock generally waives every objection that was not raised, with the narrow exception of privilege.

  3. 3

    Scope tied to Rule 26(b)(1)

    An interrogatory is proper only if the answer is relevant to a claim or defense, proportional to the needs of the case, and not protected by privilege or work-product immunity. A question that probes settlement value or trial strategy is out.

  4. 4

    Rule 33(d): business records option

    If the answer can be derived from business records and the burden of searching them is substantially the same for either side, the responding party may identify the records in lieu of summarizing them in a narrative answer.

  5. 5

    Verification under oath

    Under Rule 33(b)(3) and (b)(5) the responding party (not just counsel) must verify the answers under oath. The signed verification is what makes the answer usable at trial to impeach a shifting witness.

Types in Practice

Special vs Form vs Contention Interrogatories: Three Types Lawyers Actually Use

Most discovery sets blend all three. A special interrogatory probes the specific facts of the matter; a form interrogatory covers the standard party-witness-insurance topics; and a contention interrogatory forces the responding party to commit to a legal theory.

Form interrogatories

Pre-printed, jurisdiction-issued questions covering standard topics (party identification, witnesses, prior accidents, insurance). California Judicial Council form DISC-001 is the leading example; the Family Law analogue is DISC-001-FL. Form interrogatories are time-efficient because the responding party recognizes the questions, but the canned format limits what counsel can probe.

Special interrogatories

Custom-drafted questions targeted at the specific facts of the matter. Under California Code of Civil Procedure section 2030.030, each side may serve thirty-five special interrogatories; Federal Rule 33 caps at twenty-five. A special interrogatory should ask one fact per question; compound or argumentative phrasing draws an objection.

Contention interrogatories

Questions that force the responding party to state the legal theory behind a claim or defense and the facts that support it. The Advisory Committee Note to Federal Rule 33 expressly endorses contention interrogatories, and a court can order them held until late in discovery (after document productions) so the contentions rest on a developed record.

Companion documents in the discovery file

Interrogatories rarely travel alone. A standard discovery package layers in document requests under Rule 34 keyed to the answers, a deposition notice under Rule 30 for the signing party, and requests for admission under Rule 36 calibrated to lock in uncontested facts. For pre-suit demand work that precedes the discovery phase, route the matter through demand letter counsel.

Response Process

How to Answer Interrogatories: The Six-Step Response Process

A clean interrogatory response moves in six steps: calendar the clock, read every question twice, draft specific objections, draft narrative answers based on personal knowledge, verify under oath, and serve and supplement. For matters with a contested or evidence-heavy record, route the responses through a discovery attorney so the objections preserve every available ground.

Push Back on Deficient Responses
  1. 1

    Step 1

    Calendar the 30-day clock

    Federal Rule 33(b)(2) starts the response clock on the day of service. Local rules may add three days for mail service. Docket the deadline the day the requests arrive so the response is filed inside the window; a missed deadline generally waives objections under the well-known waiver rule.

  2. 2

    Step 2

    Read every interrogatory twice

    Mark each question for the answer category (factual recitation, identification list, document reference, contention). Flag the questions that have objection grounds (overbroad, vague, undue burden, calls for legal conclusion, attorney-client privilege, work-product immunity).

  3. 3

    Step 3

    Draft objections with the basis stated

    Rule 33(b)(4) requires that objections state the grounds with specificity. Boilerplate objections ("vague and overbroad") that do not explain why are disfavored and routinely overruled. If the responding party has knowledge but objects, the answer must be qualified as "subject to and without waiving the foregoing objection."

  4. 4

    Step 4

    Draft narrative answers based on personal knowledge

    Answer in the first person, in narrative form, based on facts within the party's knowledge or reasonably available through inquiry. For damages, identify the calculation and the source documents. For witnesses, identify each by name, last-known address, and the substance of the testimony.

  5. 5

    Step 5

    Verify under oath, signed by the party

    Under Rule 33(b)(5) the party signs the verification page under penalty of perjury. Counsel signs the objections. Both signatures are required for the response to be properly served.

  6. 6

    Step 6

    Serve and supplement

    Serve the answers within the thirty-day window. Federal Rule 26(e) creates a continuing duty to supplement if the answer becomes incomplete or incorrect. A supplementation log inside counsel's matter file is the cleanest way to track this through the discovery period.

Aftermath

What Happens After Interrogatories: Motion to Compel and Sanctions

An interrogatory served on a party rarely returns complete answers on the first pass. The propounding party scores the response, identifies the questions that were answered with a boilerplate objection, and triggers the procedural aftermath under Federal Rule 37. The aftermath is where the high-CPC half of this practice area lives: every motion to compel, sanctions request, and fee-shifting application starts with a deficient interrogatory response.

Meet and confer first

Federal Rule 37(a)(1) requires the propounding party to certify a good-faith meet-and-confer before filing any motion to compel. A meet-and-confer letter that identifies the specific deficiency for each interrogatory is the standard prerequisite.

State analogues impose the same gate. California Code of Civil Procedure section 2030.300(b) requires a meet-and-confer declaration before a motion to compel further responses can be heard.

Motion to compel

If the meet-and-confer fails, Rule 37(a)(3)(B)(iii) authorizes a motion to compel an answer to a specific interrogatory. The motion must identify the interrogatory, the response, and why the response is evasive or incomplete.

Under Rule 37(a)(4), an evasive or incomplete answer is treated as a non-answer. The fee-shifting provision in Rule 37(a)(5) makes the losing side responsible for the moving party's costs.

Sanctions menu

Rule 37(b)(2)(A) lets the court strike pleadings, preclude evidence, treat designated facts as established, hold a non-compliant party in contempt, or enter default judgment for the most egregious discovery abuses.

The cleanest workflow puts the meet-and-confer record inside the matter file so it can be attached to the Rule 37(a)(5)(A) fee declaration if the responding party concedes only after the motion is on file.

Authority: see Cornell LII on Federal Rule of Civil Procedure 37. For drafting and motion-practice support on a deficient response, route the matter to motion to compel discovery counsel or for foundational document drafting, contract drafting services.

Interrogatories FAQs

Frequently Asked Questions About Interrogatories

Sourced from the People Also Ask box for interrogatories and interrogatories meaning.

What are the disadvantages of interrogatories?
Interrogatories are answered in writing, after consultation with counsel, so the responses lack the spontaneity of a live deposition and can be heavily wordsmithed. Answers are also limited to facts within the responding party's knowledge or available to it through reasonable inquiry, so a party with weak document retention can return short answers. Federal Rule 33(a)(1) also caps a party at twenty-five interrogatories, which forces strategic rationing. For matters where discovery responses look thin or evasive, route the matter through /motion-to-compel-discovery-attorney before the discovery cutoff so a Rule 37 motion can preserve sanctions exposure.
What's the difference between discovery and interrogatories?
Discovery is the umbrella for the fact-gathering phase of litigation; interrogatories are one of the four written-discovery tools under the Federal Rules of Civil Procedure. The other three are depositions under Rule 30, requests for production of documents under Rule 34, and requests for admission under Rule 36. Interrogatories carry the lowest cost to send but yield prepared, lawyer-drafted answers. Depositions cost the most and yield the most candor. A balanced discovery plan layers all four.
What happens after interrogatories?
Both sides read the responses, score what was answered and what was objected to, and decide whether to meet and confer on the objections, send follow-up requests for production keyed to the answers, take depositions of the signing party or third-party witnesses, or file a Rule 37 motion to compel further responses. Under Federal Rule 26(e) the responding party has an ongoing duty to supplement any answer that becomes incomplete or incorrect during the case. If a deadline was missed or an objection looks unjustified, send the matter to a motion-to-compel attorney through /get-a-quote so the meet-and-confer record is preserved.
What is an advantage to using interrogatories?
Interrogatories lock a party into a written, sworn position on a specific fact or contention. Because the response is signed under oath by the party (not just counsel) under Federal Rule 33(b)(3) and (b)(5), it can be used at trial to impeach a witness whose live testimony shifts. They are also inexpensive relative to depositions and ESI productions, which makes them the right first tool for narrowing what is actually disputed before more expensive discovery starts.
What is the purpose of interrogatories?
The purpose of interrogatories is to pin down a party's factual contentions, the names of percipient witnesses, the identity of relevant documents, and the calculations behind a damages claim before any deposition is taken. Federal Rule 33 limits each side to twenty-five interrogatories (including discrete subparts), so the questions are usually drafted to maximize the information yield per question. Contention interrogatories, in particular, ask the responding party to commit to a legal theory or factual position so it cannot be revised at trial without impeachment exposure.

Need Interrogatories Drafted or Defended?

Send the matter facts, the operative complaint, and the current scheduling order. The quote request returns a tailored discovery set, an objection plan keyed to the opposing side's likely responses, and the meet-and-confer schedule that preserves Rule 37 sanctions exposure.