A deposition Subpoena is issued to summon a person to make a sworn statement at a time and place other than at trial - usually before trial. It may also require the party to provide copies of business records, documents or other tangible things. The party giving notice of the deposition is called the subpoenaing party and the witness commanded by a deposition subpoena to appear or produce personal records is called the deponent. When personal attendance of the deponent is required, the deponent is entitled to a witness fee and mileage as provided by state statutes. Usually deposition subpoenas are issued by an officer of the court or attorney of record in the case and is served on the named individual, department, or office. The person served with the subpoena is given reasonable time to respond to it.
Relevant sections in California on Deposition Subpoena.
Cal Code Civ Proc § 2020.510
Requirements for deposition subpoena; subpoena that commands attendance, testimony and production of business records, etc.; Records pertaining to consumer
(a) A deposition subpoena that commands the attendance and the testimony of the deponent, as well as the production of business records, documents, and tangible things, shall:
(1) Comply with the requirements of Section 2020.310.
(2) Designate the business records, documents, and tangible things to be produced either by specifically describing each individual item or by reasonably particularizing each category of item.
(3) Specify any testing or sampling that is being sought.
(b) A deposition subpoena under subdivision (a) need not be accompanied by an affidavit or declaration showing good cause for the production of the documents and things designated.
(c) If, as described in Section 1985.3, the person to whom the deposition subpoena is directed is a witness, and the business records described in the deposition subpoena are personal records pertaining to a consumer, the service of the deposition subpoena shall be accompanied either by a copy of the proof of service of the notice to the consumer described in subdivision (e) of Section 1985.3, or by the consumer's written authorization to release personal records described in paragraph (2) of subdivision (c) of Section 1985.3.
(d) If, as described in Section 1985.6, the person to whom the deposition subpoena is directed is a witness and the business records described in the deposition subpoena are employment records pertaining to an employee, the service of the deposition subpoena shall be accompanied either by a copy of the proof of service of the notice to the employee described in subdivision (e) of Section 1985.6, or by the employee's written authorization to release personal records described in paragraph (2) of subdivision (c) of Section 1985.6.
Cal Code Civ Proc § 2020.230. Witness fee and mileage
(a) If a deposition subpoena requires the personal attendance of the deponent, under Article 3 (commencing with Section 2020.310) or Article 5 (commencing with Section 2020.510), the party noticing the deposition shall pay to the deponent in cash or by check the same witness fee and mileage required by Chapter 1 (commencing with Section 68070) of Title 8 of the Government Code for attendance and testimony before the court in which the action is pending. This payment, whether or not demanded by the deponent, shall be made, at the option of the party noticing the deposition, either at the time of service of the deposition subpoena, or at the time the deponent attends for the taking of testimony.
(b) Service of a deposition subpoena that does not require the personal attendance of a custodian of records or other qualified person, under Article 4 (commencing with Section 2020.410), shall be accompanied, whether or not demanded by the deponent, by a payment in cash or by check of the witness fee required by paragraph (6) of subdivision (b) of Section 1563 of the Evidence Code.