Authentication of a writing means (a) the introduction of evidence sufficient to sustain a finding that it is the writing that the proponent of the evidence claims it is or (b) the establishment of such facts by any other means provided by law.
Authentication and Proof of WritingsRequirement of Authentication
Section § 1400
This law explains how to prove that a document is real or genuine. You can do this either by presenting enough evidence to show it is what you say it is or by using any other legal method to confirm its authenticity.
document authentication proof of authenticity genuine document
Section § 1401
Before a written document can be used as evidence in court, it must first be authenticated, meaning that it must be verified as genuine.
This requirement also applies if you're using a copy or some other form of secondary evidence to present the content of a document in court.
(a)CA Evidence Code § 1401(a) Authentication of a writing is required before it may be received in evidence.
(b)CA Evidence Code § 1401(b) Authentication of a writing is required before secondary evidence of its content may be received in evidence.
authentication of documents evidence admission secondary evidence
Section § 1402
If you present a document that looks like it was changed after it was originally signed, and the changes affect the main issue in dispute, you need to explain why the changes were made. You can prove that someone else made the changes without your permission, or show that everyone involved agreed to the changes, or that the changes were made for a good reason and did not alter the document's original meaning. If you can do this, you can use the document as evidence in court. If not, you can't.
The party producing a writing as genuine which has been altered, or appears to have been altered, after its execution, in a part material to the question in dispute, must account for the alteration or appearance thereof. He may show that the alteration was made by another, without his concurrence, or was made with the consent of the parties affected by it, or otherwise properly or innocently made, or that the alteration did not change the meaning or language of the instrument. If he does that, he may give the writing in evidence, but not otherwise.
altered document document alteration genuine writing
