Evidence rules (US and UK)

Text messages as evidence in California: key Evidence Code sections

Last reviewed 2026-10-17 · 8 official sources cited below

California has its own Evidence Code, so the federal rules don’t apply in state court. Here are the sections most often relevant to text messages, quoted from the code. How a judge applies them to your messages depends on the facts.

Texts are “writings”

Evidence Code § 250 defines “writing” broadly, including “transmitting by electronic mail or facsimile, and every other means of recording upon any tangible thing, any form of communication or representation”.

Authentication (§§ 1400–1401)

• § 1401(a): “Authentication of a writing is required before it may be received in evidence.”
• § 1400: authentication means “the introduction of evidence sufficient to sustain a finding that it is the writing that the proponent of the evidence claims it is” or establishing those facts by other means provided by law.

In practice that usually means testimony from someone who took part in the conversation, plus content and context that tie the messages to the sender.

Proving content: the Secondary Evidence Rule (§ 1521)

§ 1521(a): “The content of a writing may be proved by otherwise admissible secondary evidence.” The court must exclude it if there is a genuine dispute about material terms and justice requires exclusion, or if admitting it would be unfair. A faithful printout made from the export helps avoid disputes about accuracy.

Printouts of computer information (§§ 1552–1553)

• § 1552(a): “A printed representation of computer information or a computer program is presumed to be an accurate representation of the computer information or computer program that it purports to represent.” If the other party introduces evidence that the printout is inaccurate or unreliable, the party offering it must prove its accuracy “by a preponderance of evidence”.
• § 1553(a) creates a similar presumption for printed representations of images stored on a video or digital medium, which covers screenshots and photos.

These are presumptions, not guarantees. Keep the phone and the export file so you can prove accuracy if it is challenged.

Formatting rules

California Rules of Court rule 3.1110 covers papers filed in civil cases: documents “must be consecutively paginated” starting with the first page (rule 3.1110(c)). Electronic exhibits need bookmarks to each exhibit unless filed by a self-represented party (rule 3.1110(f)(4)). Small claims hearings are more informal. The courts’ self-help guide recommends bringing the original, a copy for the judge and a copy for the other side.

Sources

1. California Evidence Code § 250 — “Writing” defined (text via California.Public.Law)
2. California Evidence Code § 1400 (text via California.Public.Law, sourced from leginfo.legislature.ca.gov)
3. California Evidence Code § 1401 (text via California.Public.Law, sourced from leginfo.legislature.ca.gov)
4. California Evidence Code § 1521 — Secondary Evidence Rule (text via California.Public.Law, sourced from leginfo.legislature.ca.gov)
5. California Evidence Code § 1552 (text via California.Public.Law, sourced from leginfo.legislature.ca.gov)
6. California Evidence Code § 1553 (text via California.Public.Law, sourced from leginfo.legislature.ca.gov)
7. California Rules of Court, rule 3.1110 — General format (Judicial Branch of California)
8. California Courts Self-Help Guide — Small claims: prepare for your trial

Sources were opened and checked on 2026-10-17. Laws and rules change; always read the current version.