Interrogatories vs. Deposition: What Sets Them Apart

What Are Interrogatories?

Interrogatories are written questions one side sends to the other during the discovery process. The other side has to answer them in writing and under oath, which means those answers become part of the formal record in the case.

You’ll usually see them early in the discovery phase, when both sides are trying to pin down the facts, understand each other’s position, and get a clearer sense of what the case involves. They can ask about key elements like:

• People
• Events
• Damages
• Documents
• The basis for certain claims and defenses

Compared with a deposition, interrogatories give the other side time to prepare careful written responses. That can make them useful for getting straightforward background information, even if they are not always the best tool for digging deeper.

In many legal proceedings, they are one of the first steps toward building stronger interrogatory responses and a more organized case strategy.

What Is a Deposition?

A deposition is a formal interview that takes place outside the courtroom during discovery. One attorney asks questions, the witness answers under oath, and a court reporter records everything. This oral examination gives both sides a chance to explore the facts in real time.

Unlike interrogatories, oral depositions allow follow-up questions on the spot. They are useful when you need to test someone’s memory, clarify vague statements, or gather essential information that may not come out fully in written answers.

The back-and-forth can also lead to more candid answers, especially when a witness has to respond immediately.

A written deposition also exists, but it is much less common. In most cases, when people talk about a deposition, they mean live questioning with attorneys present.

Interrogatories vs. Deposition: What Are the Key Differences

Interrogatories and depositions both help you gather information during discovery, but they do it in very different ways.

Here’s how they compare:

Format

The format is one of the biggest differences between the two.

With interrogatories, the other party sends a list of written questions, and the responding party answers them in writing.

The process usually gives your side time to review the questions, gather facts, and craft answers carefully before serving them. When answering interrogatories, attorneys often help shape the wording, raise discovery objections, and make sure the responses line up with the case strategy.

A deposition works very differently. It usually happens in person, though remote depositions are common as well.

A lawyer asks questions out loud, and the witness answers in real time under oath. That answer becomes sworn testimony, and a court official, such as a court reporter, creates the record.

The difference in format can shape the entire exchange. Interrogatories are slower and more controlled. Depositions are more immediate, which leaves less room to pause and refine an answer. Both still have to follow the same basic legal standards that govern discovery.

Flexibility

With written interrogatories, one party sends a fixed set of questions, and the other side responds in writing. If an answer feels vague or incomplete, you usually cannot push further in that same moment. You may need another round of discovery to clear things up, which can slow things down.

A deposition is much more flexible. You can ask deposition questions in real time, follow up right away, and change direction based on what the witness says.

That makes it easier to dig into unclear statements, test someone’s version of events, and uncover relevant information that may not show up in a carefully prepared written response.

You also get a verbatim transcript of the exchange, which can be useful later if the witness changes their story or gives a different version of the facts. So, the live back-and-forth gives depositions an edge when you need detail or a better sense of how someone responds under pressure.

Time and Cost

Interrogatories usually take less time and cost less than a deposition. In many cases, drafting and answering one set may take a few attorney hours, though bigger cases can take longer.

For a simple estimate, firms may spend a few hundred to a few thousand dollars on a set of interrogatories, depending on how many questions are involved and how much review the answers need.

Depositions usually require more time and a bigger budget. A single deposition can involve several hours of prep, a half day or a full day of questioning, and additional time to review the transcript later.

Court reporter fees, transcript costs, attorney prep, and attendance all add up. A straightforward deposition may cost a few thousand dollars, while longer or more complex depositions can climb well beyond that.

Interrogatories work well when you want basic facts at a lower cost. Depositions make more sense when the case calls for deeper answers, follow-up questions, or testimony you may want to use later.

Depth of Information

Interrogatories and depositions can both uncover useful facts, but they usually give you different levels of detail.

Interrogatories generally offer a more limited view. The questions are submitted in writing, and the answers are usually reviewed carefully before they are served.

You might get solid background facts on relevant topics, such as the names of witnesses, the date of an incident, the injuries being claimed, or the documents a party plans to rely on.

For example, one answer may identify everyone present at a car accident or list the medical providers involved after the crash.

Depositions usually go further. Lawyers can ask follow-up questions right away, press for clarification, and explore weak spots in a witness’s answer. That ability gives opposing sides a chance to hear how a person explains events in real time.

For example, a witness may list a conversation in an interrogatory response, but during a deposition, the lawyer can ask what was said, who was in the room, how certain the witness is, and why the story changed.

Who Responds

The answer depends on which discovery tool you’re using.

With interrogatories, the responding party is usually one of the parties in the case. In most situations, you are asking a plaintiff or defendant to provide written answers under oath.

For instance, in a business dispute, a company may answer through a representative with access to the necessary information. The same general rule applies under civil procedure in many jurisdictions.

With depositions, the pool is much wider. Depositions and interrogatories serve different purposes, so the people involved can look very different, too. A deposition can be taken from someone directly involved in the lawsuit or from someone who simply has useful testimony.

Examples of who may respond:

• Plaintiff
• Defendant
• Corporate representative
• Eyewitness
• Treating physician
• Expert witness
• Investigating officer
• Employee with relevant knowledge

In a civil trial, for example, depositions often help you hear directly from the people who may later testify.

Interrogatories are narrower and usually stay with the parties themselves. Because the rules can vary, many firms rely on experienced attorneys to decide who to question and which tool makes the most sense.

When Should You Use Interrogatories?

Interrogatories are a good fit when you want written answers from the opposing party early in civil litigation. They can help you pin down basic facts, narrow the disputed issues, and build a clearer record before moving on to depositions or other discovery.

Here are some common situations where interrogatories make sense:

• Early case investigation: Interrogatories can help you determine what the other side is claiming, denying, or relying on at the start of the case.
• Basic factual information: They work well for getting names, dates, documents, damages, and other core details in writing.
• Issue narrowing: Written answers can show which facts are actually disputed and which points may not need as much attention later.
• Case strategy and planning: A smart strategic use of interrogatories can help you spot weak points, test legal theories, and prepare for the next stage of discovery.
• Budget-conscious discovery: Interrogatories usually cost less than depositions, so they are often a practical first step when you need useful information without a larger expense.

When Should You Use a Deposition?

A deposition makes sense when written discovery will not give you enough detail. For instance, live questioning can help you dig deeper and gather comprehensive information that may be harder to get through interrogatories alone.

A deposition is usually needed in these situations:

• Credibility is a major issue: A deposition lets you hear how a witness answers under pressure, which can reveal hesitation, inconsistency, or uncertainty in a way written answers cannot.
• Follow-up questions will likely matter: Interrogatories may produce careful or thoughtful responses, but a deposition gives you room to press for clarification right away.
• Witness demeanor could affect the case: Tone, pause, confidence, and body language can shape how testimony comes across, especially when the facts are disputed.
• You need testimony tied closely to the evidence: Depositions are useful when you want a witness to explain documents, timelines, photos, emails, or other evidence in detail.
• You may need stronger testimony for later use: Under the Federal Rules, deposition testimony can play an important role in motion practice, impeachment, or preserving testimony for a subsequent deposition or trial strategy.

What Civil Procedure Says About Interrogatories and Depositions

The Federal Rules of Civil Procedure place both interrogatories and depositions within the broader discovery process.

Rule 26 sets the general scope of discovery, Rule 33 covers interrogatories to parties, and Rule 30 covers depositions by oral examination.

A few points make the structure easier to follow:

• Rule 26: Sets the overall scope and limits of discovery, including relevance and proportionality.
• Rule 33: Covers interrogatories, which are written questions served on parties and answered in writing under oath.
• Rule 30: Covers depositions by oral examination, where a witness gives live, sworn testimony and an officer records the answers verbatim.

The federal rules also set default limits on each tool:

• Interrogatories: Usually capped at 25, including discrete subparts, unless the court orders otherwise.
• Depositions: Usually capped at 10 per side, with a default limit of 1 day of 7 hours for each deposition, unless the court changes that limit.

Take note that this is just a general overview rather than a one-size-fits-all rule for every case. State civil procedure rules can differ, sometimes in significant ways, so you should treat this section as a federal baseline.

How Briefpoint Helps With Interrogatories and Discovery Drafting

Interrogatories offer a useful way to gather facts, but drafting responses, reviewing objections, and matching answers to relevant documents can get time-consuming.

Briefpoint is built for that part of litigation work. It helps law firms draft discovery requests and responses for interrogatories, RFAs, and RFPs much faster, with objection-aware drafting and workflows built for civil cases.

Autodoc adds another layer when document-heavy discovery is involved.

You can upload the complaint, RFPs, and case files, then use AutoDoc to find responsive materials, organize them, and generate a Bates-numbered production with a Word response that includes page-level Bates citations. That can save a huge amount of manual review and drafting time.

Briefpoint also supports Supplemental Responses, so you can create updated responses for interrogatories, RFAs, and RFPs while keeping earlier answers intact and easy to reference.

Want to see all these features in action?

Book a demo today.