To use a foreign language document as evidence in a California court, it must be accompanied by a translation into English and a translator certification. See Rule of Court 3.1110 (g) effective Jan 1, 2017:
California Rules of Court
Rule 3.1110. General format
(g) Translation of exhibits
Exhibits written in a foreign language must be accompanied by an English translation, certified under oath by a qualified interpreter.
Note that the translator certification need not be notarized, as is the case when recording a translation with the county clerk/recorder. The standard qualification required is to be a Certified Court Interpreter.
The Judicial Council has a form that the court clerk might require, and it looks like this: