Prepare to tell the truth clearly, not to perform a script

Counsel should confirm the witness's role, the issuing court, case number, deposition notice or subpoena, date, time, place or remote platform, recording methods, interpreter or accommodation needs, document requests, protective orders, confidentiality provisions, stipulations, and any organizational topics. A party witness, nonparty, expert, records custodian, and organization designee can have different duties and preparation needs. Oklahoma § 3230 and Federal Rule of Civil Procedure 30 are similar in structure but should not be treated as identical.

The responsible lawyer should also explain who will attend, who asks questions, who may object, what the court reporter does, whether video is used, and how the session ends. Objection and instruction practices turn on the forum and circumstances. A general guide cannot tell a witness to refuse a question. If privilege, work product, confidentiality, criminal exposure, health, safety, harassment, or a protective order may be involved, counsel should resolve the protocol before testimony rather than improvising in the room.

Counsel may review pleadings, prior statements, discovery responses, correspondence, photographs, records, timelines, and likely exhibits, but should choose materials deliberately. Federal Rule of Evidence 612 and related law can create questions when a writing refreshes memory. Privilege and work-product protection can also be affected by the subject, witness, materials, and use. A witness should not assemble a private file, search old accounts, delete content, annotate originals, or discuss testimony with other witnesses without advice from the responsible lawyer.

During review, the witness should identify what is personally remembered, what is recognized only because of a record, what remains uncertain, and what earlier statement may be inaccurate or incomplete. Dates, distances, speeds, quotations, diagnoses, company roles, and motives should not be guessed. An attorney can test whether an answer is understood, help the witness organize chronology, and explain ambiguous terminology. The attorney should not supply facts, demand memorized wording, or train the witness to evade a fair question.

Wait for the full question and any objection. If the question is unclear, compound, uses an unfamiliar term, assumes a disputed fact, or refers to an unseen document, ask for clarification or the item. Answer the question truthfully at the level needed to be accurate. Do not volunteer a speech merely to help one side. Do not use answer-only-the-question advice as a device to conceal a necessary qualification.

A yes or no can be misleading when the truthful answer requires context; the witness can say so plainly.

Speak instead of nodding, avoid sarcasm, and allow the court reporter to capture one speaker at a time. Do not speculate about another person's thoughts or a technical subject outside the witness's knowledge. Estimates should be identified as estimates with their basis. If the witness realizes an earlier answer was wrong, the witness should say so and correct it through the process counsel identifies. Accuracy matters more than defending a prior mistake.

A witness who needs water, medication, a restroom, food, an accessibility accommodation, or time to regain focus should tell counsel. Ordinarily the pending question should be answered first unless the responsible lawyer directs otherwise or a health or safety issue makes that impractical. Courts differ on lawyer-witness conferences during a deposition, particularly while a question is pending. The witness should follow the responsible lawyer's case-specific direction and should not use a break to rehearse or alter testimony.

For an exhibit, identify what the document is, whether the witness has seen it, whether it is complete, and whether the question points to the correct language. Read the relevant portion before answering. A logo, email header, signature image, spreadsheet, or photograph does not establish authorship, transmission, completeness, date, or accuracy by itself. If the copy is unreadable, missing pages, lacks attachments, or uses an unfamiliar version, state the problem rather than assuming it away.

Federal Rule 30(e) provides a conditional request-and-review process after notice that the transcript or recording is available. Oklahoma § 3230 has its own procedure; stipulations or orders may modify practice. Before the deposition ends, counsel should decide and document whether and how to request review. Errata do not permit rewriting unfavorable testimony; the original, changes, and reasons remain examinable.

Preserve notes and communications as counsel instructs; do not discuss substance with other witnesses or post about the case. Counsel should record promised documents, facts to investigate, privilege issues, exhibit gaps, and case-theory effects. Give the witness a concrete next step, not a prediction. Testimony remains one part of a record requiring context and legal analysis.