Receiving pages of numbered legal questions can make a lawsuit suddenly feel much more serious. Those questions are often interrogatories, one of the main tools parties use during civil discovery to learn what the other side knows, what facts support its position, and where important evidence may be found. Understanding how they work can help you recognize what is being requested and why response deadlines matter.
Short answer: Interrogatories are written questions one party in a civil lawsuit sends to another party during discovery. In federal court, Rule 33 generally permits up to 25 questions, including discrete subparts, and responses or objections are normally due within 30 days. Answers must generally be given separately, fully, in writing, and under oath.
Written Discovery Questions at a Glance
| Question | General federal rule |
|---|---|
| What are they? | Written discovery questions sent from one party to another |
| Who can receive them? | Another party to the lawsuit |
| Federal limit | Generally 25, including discrete subparts |
| Response deadline | Generally 30 days after service |
| Must answers be sworn? | Yes, answers are made in writing under oath. |
| Can you object? | Yes, but the grounds should be stated specifically. |
| Can answers be used later? | Yes, subject to the Federal Rules of Evidence |
| Do state rules differ? | Yes, sometimes significantly. |
These are federal-court rules rather than universal rules for every U.S. lawsuit. State courts maintain their own civil-procedure rules, which may change the number of permitted questions, available forms, deadlines, service requirements, and other details. Anyone dealing with an active case should therefore check the rules for the court where the lawsuit is pending rather than relying on a national summary alone.
What Are Interrogatories in a Lawsuit?
They are a form of written discovery, meaning they are used to obtain information before trial rather than to question a witness live in court. One party prepares a numbered list of questions and serves it on another party, which must respond according to the applicable procedural rules. They are commonly used to identify people, events, documents, defenses, damages, witnesses, and other facts connected to the dispute.
Their main advantage is efficiency. Instead of scheduling a deposition simply to learn basic names, dates, addresses, or factual positions, a lawyer can request that information in writing and use the responses to decide what should be investigated next. The answers can also help narrow disputed issues and reveal areas that deserve follow-up through document requests, depositions, or other discovery tools.
These questions are directed to parties, not ordinary third-party witnesses. If information is needed from a person or organization that is not a party to the case, another discovery procedure, such as a subpoena or deposition, may be appropriate instead. That distinction is important because the discovery device used determines both who must respond and what procedural rules apply.
7 Federal Rules to Know About Written Discovery Questions
Federal Rule of Civil Procedure 33 supplies the basic framework for these written questions in federal civil litigation. These seven points explain the rules most people are likely to encounter. State-court procedures can differ, so they should not be treated as replacements for the rules governing a particular case.
- The usual federal limit is 25. A party may generally serve no more than 25 written questions on another party without an agreement or court order. Discrete subparts count toward that total.
- Questions must fall within the permitted scope of discovery. Rule 33 ties their scope to Rule 26, which generally focuses discovery on nonprivileged information relevant to a claim or defense and proportional to the needs of the case.
- Responses are generally due within 30 days. The responding party ordinarily has 30 days after service to provide answers and objections, although an agreement or court order can change that period.
- Each question must be addressed separately. To the extent a question is not properly objected to, it generally must be answered separately and fully in writing.
- Answers are made under oath. The person providing the substantive answers signs them, while an attorney who makes objections signs those objections.
- Objections should be specific. Rule 33 requires the grounds for an objection to be stated with specificity, and an untimely objection may be waived unless the court excuses the failure for good cause.
- Business records can sometimes supply the answer. When an answer can be determined from business records and the burden of finding it is substantially the same for both sides, Rule 33 may allow the responding party to identify the records instead of writing a conventional narrative answer.
What Can These Questions Ask About?
The questions normally focus on information connected to the claims and defenses in the lawsuit. Federal discovery is governed by Rule 26’s relevance and proportionality principles, meaning a request does not automatically become appropriate simply because a party would like to know the answer. Courts can consider factors such as the importance of the issues, access to information, the parties’ resources, and whether the burden or expense of discovery outweighs its likely benefit.
Depending on the case, questions may ask a party to:
- Identify people who witnessed an event.
- State important dates, locations, and communications.
- Explain the factual basis for a claim or defense.
- Identify relevant documents or electronic records.
- Describe injuries, losses, expenses, or other claimed damages.
- Identify employers, healthcare providers, experts, or other relevant people.
- Explain factual contentions concerning an allegation.
- Identify insurance, contracts, transactions, or business records relevant to the dispute.
Federal Rule 33 also makes clear that a question is not automatically improper merely because it requests an opinion or contention involving facts or the application of law to facts. A court can nevertheless postpone some contention questions until later in discovery when answering them earlier would be premature. Questions seeking purely abstract legal analysis may raise different issues because discovery remains tied to the permitted scope of Rule 26.
Examples of Written Discovery Questions
The exact wording depends heavily on the lawsuit. A personal injury action might focus on an accident, medical treatment, prior injuries, and damages, while an employment or commercial case would ask very different questions. The examples below illustrate the general format rather than language that should automatically be copied into a real case.
- Identify every person you believe witnessed the incident described in the complaint.
- Describe the facts on which you base your claim that the defendant caused your injury.
- Identify each healthcare provider who treated you for injuries you attribute to the incident.
- State the amount of lost income you claim and explain how that amount was calculated.
- Identify each document you contend supports the defense described in paragraph 12 of your answer.
- State whether you communicated with the plaintiff about the disputed agreement and identify the approximate date and method of each communication.
Good questions are usually targeted enough to obtain useful information without creating unnecessary ambiguity. Overly broad questions can create disputes about scope, relevance, burden, or the meaning of particular terms. Because even a seemingly simple question can affect litigation strategy, actual discovery requests should be evaluated in the context of the applicable case and court rules.
How Do You Answer Interrogatories?
The first step is to determine the actual deadline rather than assuming it from a general online guide. In federal court, the default under Rule 33 is 30 days after service, but the parties may sometimes agree to a different period, and a judge can also order another deadline. A scheduling order, local rule, or case-specific order may affect what must be done and when.
A practical response process usually involves:
- Read every question carefully and identify each part of what is being requested.
- Gather information reasonably available to the responding party.
- Compare proposed answers with pleadings, records, prior discovery, and other case information for consistency.
- Identify questions that may require a legitimate objection.
- Answer the portions that are not objectionable as fully as required.
- Review names, dates, amounts, and factual statements for accuracy.
- Complete the required signatures or verification before serving the responses.
- Keep a copy of the final responses and supporting information.
Responses should not be treated like an informal questionnaire. In federal practice, substantive answers are provided under oath, and those answers may later be used to the extent permitted by the rules of evidence. Careful review matters because an inaccurate answer can create problems when testimony, documents, or other evidence later tell a different story.
A party’s responsibility may also continue after the first response is served. Under Rule 26(e), a party generally must timely supplement or correct an interrogatory response when it learns that the response is materially incomplete or incorrect and the new information has not otherwise been made known during discovery or in writing. That makes accuracy an ongoing issue rather than something that necessarily ends on the response date.
Can You Object to an Interrogatory?
Yes, but an objection is not simply a way to avoid an inconvenient question. Federal Rule 33 requires the grounds for the objection to be stated with specificity, and a party generally must answer the portion of a question that is not covered by a valid objection. Failing to object on time can also result in waiver unless the court excuses the delay for good cause.
Common issues that may lead to objections include:
| Possible objection | What it generally concerns |
|---|---|
| Relevance | The requested information is not sufficiently connected to the claims or defenses. |
| Overbreadth | The question sweeps more broadly than the dispute reasonably requires. |
| Undue burden | Responding would impose disproportionate work, expense, or difficulty. |
| Vagueness or ambiguity | Important words or the scope of the question are unclear. |
| Attorney-client privilege | The request seeks protected attorney-client communications. |
| Work-product protection | The request seeks certain protected litigation preparation material. |
| Compound or excessive subparts | A question may contain multiple discrete inquiries affecting numerical limits. |
Whether an objection succeeds depends on the actual wording, governing law, and circumstances of the case. Courts can reject boilerplate or unsupported objections. Parties are generally expected to explain the basis of an objection rather than merely attaching a label such as “overbroad” without support. California’s court self-help materials similarly advise responding parties that objections require a stated reason, illustrating why jurisdiction-specific guidance matters.
What Happens If You Ignore Written Discovery?
Ignoring properly served discovery can have consequences beyond missing a paperwork deadline. Under Federal Rule 37, the requesting party may seek an order compelling an answer when a party fails to answer an interrogatory, and an evasive or incomplete answer can be treated as a failure to answer. The rule generally requires a good-faith effort to resolve the discovery dispute before asking the court to intervene.
Continued failure can become more serious if a court issues a discovery order and that order is disobeyed. Depending on the circumstances, Rule 37 authorizes measures ranging from payment of expenses to evidentiary restrictions and, in sufficiently serious situations, sanctions affecting claims, defenses, pleadings, or judgment. The appropriate result is case-specific, but complete silence is not a safe substitute for timely answers, objections, an agreed extension, or an appropriate request for court protection.
Can the Parties Extend the Deadline?
Sometimes they can. Rule 29 generally permits parties in federal litigation to stipulate to modifications of discovery procedures. Court approval is still necessary when extending discovery would interfere with dates the court has already set for completing discovery, hearing a motion, or holding trial. The safest approach is therefore to obtain any extension clearly and in accordance with the governing rules rather than assuming that an informal conversation changed the deadline.
This is where the distinction between a casual understanding and a formal procedural agreement becomes important. Inrockry’s guide to stipulations in legal proceedings explains how parties can agree on procedural matters and why the binding effect of an agreement depends on the governing rule and its form. Discovery deadlines are a good example of why the exact agreement and the court’s schedule both matter.
Written Questions vs. Other Types of Discovery
Civil discovery includes several tools because different types of evidence require different methods. Written questions are useful for obtaining explanations and identifying information, but they are not always the best device for obtaining documents, testing whether a fact is disputed, or questioning someone in real time. Understanding the differences helps explain why a lawsuit may involve several discovery requests at the same time.
| Discovery method | Main purpose | Typical response |
|---|---|---|
| Interrogatories | Ask another party written questions. | Written answers under oath |
| Requests for production | Obtain documents, ESI, or inspect specified items. | Production or written response/objection |
| Requests for admission | Ask a party to admit or deny specified matters. | Admission, denial, explanation, or objection |
| Depositions | Question a party or witness directly. | Oral sworn testimony |
| Subpoenas | Obtain testimony, documents, or other material from appropriate persons, including nonparties. | Depends on the subpoena |
An interrogatory might identify the names of employees involved in a transaction, for example, while a request for production could seek their relevant emails and a deposition could later explore their recollection. A request for admission serves another function by asking a party to admit particular facts or the authenticity of documents. These tools often work together rather than competing with one another.
Federal and State Interrogatory Rules Are Not the Same
One of the easiest mistakes is to find a federal rule online and assume it controls every civil lawsuit in the United States. State courts have their own civil-procedure systems, and those systems can impose different numerical limits, deadlines, definitions, approved forms, and requirements. Cornell’s Legal Information Institute notes that state rules generally follow many of the same basic concepts but can vary in important ways.
California offers a useful example because its court system provides standardized form interrogatories for certain civil cases. The California Courts self-help materials explain that the requesting party checks the questions it wants answered and that the responding party addresses those selected questions individually. This is different from assuming that every jurisdiction uses only attorney-drafted sets of questions.
The practical rule is simple: identify the court first and research the discovery procedure second. A federal case requires attention to the Federal Rules, the district’s local rules, scheduling orders, and case-specific court orders, while a state action requires the applicable state and local procedure. A deadline or question limit taken from the wrong jurisdiction can be worse than having no answer at all.
Frequently Asked Questions
What does “interrogatory” mean in simple terms?
An interrogatory is a written question used during the discovery stage of a lawsuit. One party sends the question to another party to obtain information relevant to the case, and the recipient responds under the rules governing that court. In federal civil litigation, Rule 33 is the primary rule governing this discovery method.
How many written questions can one party serve in federal court?
The general federal limit is 25 interrogatories served by one party on another, and discrete subparts count toward that number. Parties can sometimes agree to additional discovery, or a court may permit more when the applicable standards are satisfied. State courts may use different numerical limits, so 25 should not be assumed to apply to every U.S. case.
How long do you have to respond?
Federal Rule 33 generally provides 30 days after service for answers and objections. That period can be changed by stipulation or court order in appropriate circumstances, and other procedural rules may affect how deadlines are calculated. State deadlines can differ, so the governing court’s rules and orders should always be checked.
Are interrogatory answers under oath?
Yes, substantive answers under Federal Rule 33 are made separately and fully in writing under oath to the extent the question is not objected to. The person who makes the answers signs them, while the attorney signs the objections. This sworn nature is one reason responses should be reviewed carefully for factual accuracy before they are served.
Can you refuse to answer an interrogatory?
A party may assert an appropriate objection rather than answer legitimately objectionable material, but simply refusing to participate can create serious discovery problems. Federal rules require objections to be specific, and the non-objectionable portion generally still must be answered. If a discovery dispute remains unresolved, the requesting side may seek relief from the court under Rule 37.
Can interrogatory answers be changed later?
They can sometimes be supplemented or corrected, and in some circumstances federal rules require that correction. Rule 26(e) generally requires a timely supplement when a party learns that an earlier response is materially incomplete or incorrect and the corrective information has not otherwise been disclosed. A party should therefore not assume that discovering an important mistake can simply be ignored because the original response has already been served.
The Bottom Line
Interrogatories are written discovery questions designed to uncover relevant information from another party before a civil case reaches trial. In federal court, the most important starting points are the general 25-question limit, the 30-day response period, the requirement for sworn written answers, and the need to state objections specifically. State and local procedures can differ substantially, so anyone responding to actual discovery should rely on the rules and court orders governing that particular case rather than treating a general article as legal advice.
For more plain-English coverage of court procedure and U.S. legal topics, readers can browse Inrockry’s Law section. The site also explains related concepts such as stipulations, employment rules, court records, and other legal terms that readers may encounter in documents or litigation. These resources are educational and do not replace advice from a lawyer licensed in the relevant jurisdiction.
