LawWiki
HomeCodesSearchGlossaryAPIAbout
LawWiki

Plain English summaries of California law with zero-hallucination AI. Every summary is verified against official source text.

Product

  • Search
  • Codes
  • About

Legal

  • Privacy Policy
  • Terms of Service
  • Disclaimer

© 2026 LawWiki. All rights reserved.

HomeEvidence CodeDiv. 7Ch. 1Art. 3§ 870 Witness Testimony On Sanity

§ 870 Witness Testimony On Sanity

Evidence Code·California
AI Summary·Official Text·Key Terms·Related Statutes·References
AI SummaryVerified

§ 870 Witness Testimony On Sanity

Key Takeaways

  • •Only certain people can give their opinion on whether someone is mentally stable.
  • •These people must be very close to the person in question.
  • •They can also be someone who saw the person sign an important document and can talk about their mental state at that time.
  • •Or they can be experts who are allowed by other laws to give their opinion.

Example

Your best friend starts acting very strangely and people are worried about their mental health.

You can tell a judge what you think about your friend's mental state because you know them very well. But a random person who just met your friend cannot do this.

AI-generated — May contain errors. Not legal advice. Always verify source.

Official Source
View on CA.gov

§ 870 Witness Testimony On Sanity

A witness may state his opinion as to the sanity of a person when: (a) The witness is an intimate acquaintance of the person whose sanity is in question; (b) The witness was a subscribing witness to a writing, the validity of which is in dispute, signed by the person whose sanity is in question and the opinion relates to the sanity of such person at the time the writing was signed; or (c) The witness is qualified under Section 800 or 801 to testify in the form of an opinion. (Enacted by Stats. 1965, Ch. 299.)

Last verified: January 22, 2026

Key Terms

intimate acquaintancesubscribing witnessqualified under Section 800 or 801

Related Statutes

  • § 1411 Witness Testimony Not Required
  • § 1412 Witness Testimony Authentication Rules
  • § 1413 Document Authentication Witnesses
  • § 1450 Evidence Burden Presumptions
  • § 1451 Acknowledgment Certificate Evidence

References

  • Official text at leginfo.legislature.ca.gov
  • California Legislature. Evidence Code. Section 870.
View Official Source