§ 2020.010.Persons within the state; approved methods
Title 4. Civil Discovery Act · Chapter 6. Nonparty Discovery · Article 1. General Provisions · Enacted 2004 · no amendments on record · Last verified July 29, 2026
In one sentenceSection 2020.010 authorizes discovery from a nonparty within California through an oral deposition, a written deposition, or a deposition for production of business records, and establishes that a deposition subpoena is the exclusive process for compelling that discovery.
(a)Any of the following methods may be used to obtain discovery within the state from a person who is not a party to the action in which the discovery is sought:
(1)An oral deposition under Chapter 9 (commencing with Section 2025.010).
(2)A written deposition under Chapter 11 (commencing with Section 2028.010).
(3)A deposition for production of business records and things under Article 4 (commencing with Section 2020.410) or Article 5 (commencing with Section 2020.510).
(b)Except as provided in subdivision (a) of Section 2025.280, the process by which a nonparty is required to provide discovery is a deposition subpoena.
Plain-English Summary
Discovery from someone who isn't a party to the case works differently from discovery between the parties themselves. This section marks that difference by listing the only three ways to get discovery from a nonparty located within the state: an oral deposition, a written deposition, or a deposition aimed at producing business records and things. There's no interrogatory or inspection demand route for nonparties; those tools reach only parties to the action.
And there's only one process for compelling any of the three: the deposition subpoena. Whether a party wants live testimony, written answers under a written deposition, or just a stack of business records, a deposition subpoena is what makes the nonparty's participation mandatory rather than voluntary. The rest of this chapter builds out exactly how that subpoena works.
Frequently Asked Questions
Can a party send interrogatories directly to a nonparty witness?
No. Section 2020.010 limits nonparty discovery to oral depositions, written depositions, and depositions for production of business records.
What process compels a nonparty to participate in discovery?
A deposition subpoena. That's the exclusive process for requiring a nonparty's compliance under this chapter.
Does this section cover discovery from someone located outside California?
No. It governs discovery within the state; out-of-state discovery follows separate interstate and international deposition procedures.
Amendment History
(Added by Stats.2004, c. 182 (A.B.3081), § 23, operative July 1, 2005.)
Source & verification. Section text is reproduced verbatim from
the West's Annotated California Codes / Thomson Reuters. Enacted by the California Legislature.
Last verified July 29, 2026.
· Official source
Also known as:nonparty discovery methods californiadeposition subpoena exclusive process