California Code, Evidence Code - EVID § 1410.5

(a) For purposes of this chapter, a writing shall include any graffiti consisting of written words, insignia, symbols, or any other markings which convey a particular meaning.

(b) Any writing described in subdivision (a), or any photograph thereof, may be admitted into evidence in an action for vandalism, for the purpose of proving that the writing was made by the defendant.

(c) The admissibility of any fact offered to prove that the writing was made by the defendant shall, upon motion of the defendant, be ruled upon outside the presence of the jury, and is subject to the requirements of Sections 1416, 1417, and 1418.