Discovery in Civil Litigation: Tools, Subpoenas, and Sanctions

Discovery in civil litigation is the pretrial phase in which each side investigates the other’s claims and defenses by exchanging documents, answering written questions under oath, and taking live testimony. In federal court, the process runs on Rules 26 through 37 and Rule 45 of the Federal Rules of Civil Procedure, each of which supplies specific tools with fixed deadlines and firm limits.¹ The point is to force cases to be decided on the actual facts rather than on which side hides evidence more effectively.

How Discovery Begins

Before either side serves a single request, the parties must meet and confer under Rule 26(f). At that conference they discuss the claims and defenses, explore early settlement, and build a proposed discovery plan covering timing, subjects, the handling of electronically stored information, and any anticipated privilege disputes.¹

The plan goes to the judge, who then issues a scheduling order under Rule 16(b) setting firm deadlines for completing discovery, amending pleadings, and filing motions.² Once the discovery cutoff passes, no further requests can be served without the court’s permission. Missed deadlines can produce sanctions or the exclusion of evidence at trial.

Mandatory Initial Disclosures

Rule 26(a)(1) requires each party to hand over four categories of baseline information within 14 days of the Rule 26(f) conference, without waiting to be asked:¹

The name, address, and phone number of each person likely to have relevant information, along with the subjects that person knows about.
A copy or description of documents, electronically stored information, and tangible things the party may use to support its claims or defenses.
A breakdown of each category of damages claimed, with the supporting documents available for inspection.
Any insurance policy under which an insurer could be liable to satisfy a judgment or reimburse payments.

A party that skips or slow-walks these disclosures may be barred from using the omitted information at trial or at a hearing.³

What Information Is Discoverable

Under Rule 26(b)(1), parties may seek discovery on any nonprivileged matter relevant to any party’s claim or defense, so long as the request is proportional to the needs of the case.¹ Information does not have to be admissible at trial to be discoverable. Proportionality weighs the importance of the issues, the amount in controversy, each side’s relative access to the information, and whether the burden of producing it outweighs the likely benefit.

Privilege and Work Product

Two doctrines do most of the shielding. Attorney-client privilege covers confidential communications between a client and their lawyer made for the purpose of obtaining legal advice, and it is absolute unless the client waives it.⁴ The work product doctrine under Rule 26(b)(3) protects documents and tangible things prepared in anticipation of litigation. Work product protection can be overcome if the requesting party shows substantial need and cannot obtain the equivalent without undue hardship, but even then the court must shield the mental impressions, conclusions, and legal theories of the attorney.¹

Withholding is not silent. Rule 26(b)(5) requires a party to expressly assert the claim and describe the withheld materials in enough detail for the other side to test it.¹ In practice that means a privilege log listing each document, its date, author and recipients, and the basis for the claim. A vague log invites a motion to compel.

Protective Orders

When a request threatens trade secrets, personal privacy, or unreasonable burden, a party can ask the court for a protective order under Rule 26(c). The moving party must show good cause and certify a good-faith attempt to resolve the dispute informally first.¹ Courts have wide discretion to narrow the scope, require confidential treatment, or bar a particular line of questioning outright.

Clawback Agreements

In document-heavy cases, accidental disclosure of privileged material is nearly inevitable. A clawback agreement entered as a court order under Federal Rule of Evidence 502(d) provides that producing privileged or work-product material does not waive the privilege, whether the disclosure was inadvertent or intentional.⁵ The protection reaches other federal and state proceedings as well, which is why parties producing large volumes of electronically stored information almost always want a 502(d) order in place before production begins.

The Written Discovery Tools

Written discovery does most of the work in most cases. Three tools dominate, and each carries a 30-day response window.

Interrogatories

Interrogatories are written questions the other party must answer in writing and under oath. Rule 33 caps them at 25 per party, subparts included, unless the court allows more or the parties agree.⁶ Common targets are witness identities, the factual basis for a claim, and how damages were calculated. Responses are due within 30 days, objections must be stated with specificity, and the person answering signs the responses. Because of the 25-question cap, experienced litigators avoid burning interrogatories on information that could just as easily be pulled through document requests.

Requests for Production

Rule 34 lets a party demand that the other side produce documents, electronically stored information, and tangible things for inspection, copying, or testing.⁷ Each item or category must be described with reasonable particularity. This is the tool that reaches emails, contracts, financial records, text messages, and maintenance logs. There is no federal cap on the number of requests. Responses are due within 30 days, and the responding party must either produce the materials or state specific objections for each category.

Requests for Admission

Requests for admission under Rule 36 ask the other side to admit or deny specific facts, narrowing what actually needs to be tried.⁸ An admitted matter is conclusively established for the case. The trap: if a party does not respond within 30 days, every request is automatically deemed admitted. That default is one of the most punishing in civil procedure. A party that ignores a set of admission requests can find critical facts locked in against it, and courts will allow withdrawal of a deemed admission only if the requesting side would not be prejudiced, a hard standard to meet once the other side has built its strategy around the admissions.

Depositions and Examinations

A deposition is live, sworn testimony taken outside the courtroom, usually in a lawyer’s conference room with a court reporter recording every word. Depositions gather information and lock in testimony that can be used at trial if the witness later changes the story or becomes unavailable.

Under Rule 30, the noticing party gives reasonable written notice of the time, place, and identity of each witness. Each side is limited to 10 depositions, and each deposition is capped at one day of seven hours unless the parties agree or the court orders otherwise.⁹ Rule 31 offers a cheaper alternative: the questioning party submits written questions to an officer, who reads them to the witness and records the answers.¹⁰ Written questions work for straightforward factual matters but sacrifice the ability to adjust in real time based on the answers.

When a party’s physical or mental condition is genuinely in issue, most often in personal injury litigation, Rule 35 allows the opposing side to seek a court-ordered examination by a licensed professional. Because the tool is more intrusive than the others, the requesting party must move for it on good cause, and the order specifies the time, place, scope, and examiner.¹¹

Expert Witnesses

Experts get their own disclosure regime. Under Rule 26(a)(2), each side must identify any expert it plans to call at trial, and a retained expert must provide a written report.¹² The report must contain:

A complete statement of the expert’s opinions and the basis for each one
The facts or data the expert considered
Any exhibits that summarize or support the opinions
The expert’s qualifications, including publications from the previous 10 years
A list of all cases in which the expert testified at deposition or trial in the previous four years
A statement of the expert’s compensation for the engagement

Expert disclosures are typically due at least 90 days before trial, with rebuttal reports due within 30 days after the initial disclosure.¹ An expert who submits a vague or conclusory report risks being barred from testifying, and trial testimony is generally confined to what the report covers. Draft reports and most attorney-expert communications are protected as work product under Rule 26(b)(4), so the opposing side cannot demand early drafts or strategic exchanges between the lawyer and the expert.

Reaching Non-Parties Through Subpoenas

Not every piece of relevant evidence sits with someone in the lawsuit. Rule 45 supplies the subpoena, a court-issued command to testify, produce documents, or permit inspection of premises.¹³ A non-party served with a document subpoena can serve a written objection within 14 days. Subpoenas also carry a witness-fee obligation: under 28 U.S.C. § 1821, the issuing party must pay the witness $40 per day plus travel expenses, with common-carrier fare at actual cost or private-vehicle travel at the federal mileage rate, and tolls, parking, and taxi fares between lodging and transportation terminals also reimbursable.¹⁴

The Ongoing Duty to Supplement

Discovery responses do not finalize on delivery. Under Rule 26(e), a party that learns any disclosure or response is materially incomplete or incorrect must supplement or correct it in a timely manner.¹ The duty is ongoing and reaches initial disclosures, interrogatory answers, production responses, and expert reports. For experts, additions and changes must be disclosed by the deadline for pretrial disclosures. A party that fails to supplement may be barred from using the omitted information or witness at trial, and the court can add attorney’s fees on top.³

What Happens When Someone Breaks the Rules

Discovery only works if both sides participate in good faith. Rule 37 gives courts a wide range of tools when they don’t.

Motions to Compel and Fee Shifting

When a party refuses to answer, produce, or cooperate at a deposition, the other side can file a motion to compel. If the court grants it, the losing party or its attorney generally must pay the winner’s reasonable expenses, including attorney’s fees, for having to bring the motion.³ The court will withhold fees only where the nondisclosure was substantially justified or the movant did not try to resolve the dispute informally first. Fee shifting runs both ways: a denied motion can leave the movant paying the other side’s costs.

Sanctions for Disobeying a Discovery Order

Once a court order is on the books, ignoring it raises the stakes sharply. Under Rule 37(b)(2), the court can:³

Deem specified facts established against the violator.
Prohibit the disobedient party from supporting or opposing specific claims.
Strike pleadings in whole or in part.
Dismiss the case or enter default judgment.
Hold the party in contempt, available for most violations though not for refusal to submit to a physical or mental examination.

Destroying Electronic Evidence

Spoliation of electronically stored information has its own rule. Under Rule 37(e), if a party failed to take reasonable steps to preserve electronic evidence that should have been kept, and the evidence cannot be restored or replaced, the court can order measures to cure the prejudice. Where the destruction was intentional, meaning done with the purpose of depriving the other side of the evidence, the court can instruct the jury to presume the lost information was unfavorable, dismiss the action, or enter default judgment.³ Once litigation is reasonably anticipated, a litigation hold should go out immediately to suspend routine deletion of emails, messages, and files. Failing to do so is one of the most costly mistakes in modern civil litigation.

1
Legal Information Institute. Federal Rules of Civil Procedure Rule 26 – Duty to Disclose; General Provisions Governing Discovery
2
Legal Information Institute. Federal Rules of Civil Procedure Rule 16 – Pretrial Conferences; Scheduling; Management
3
Legal Information Institute. Federal Rules of Civil Procedure Rule 37 – Failure to Make Disclosures or to Cooperate in Discovery; Sanctions
4
Legal Information Institute. Attorney-Client Privilege
5
Legal Information Institute. Federal Rules of Evidence Rule 502 – Attorney-Client Privilege and Work Product; Limitations on Waiver
6
Legal Information Institute. Federal Rules of Civil Procedure Rule 33 – Interrogatories to Parties
7
Legal Information Institute. Federal Rules of Civil Procedure Rule 34
8
Legal Information Institute. Federal Rules of Civil Procedure Rule 36 – Requests for Admission
9
Legal Information Institute. Federal Rules of Civil Procedure Rule 30
10
Legal Information Institute. Federal Rules of Civil Procedure Rule 31 – Depositions by Written Questions
11
Legal Information Institute. Federal Rules of Civil Procedure Rule 35 – Physical and Mental Examinations
12
Legal Information Institute. Expert Witness Reports
13
Legal Information Institute. Federal Rules of Civil Procedure Rule 45 – Subpoena
14
Office of the Law Revision Counsel. 28 USC 1821 – Per Diem and Mileage Generally; Subsistence