Cal. Evidence Code - EVID § 1070. Section 1070.
(a)
A publisher, editor, reporter, or other person connected with or employed upon a newspaper, magazine, or other periodical publication, or by a press association or wire service, or any person who has been so connected or employed, cannot be adjudged in contempt by a judicial, legislative, administrative body, or any other body having the power to issue subpoenas, for refusing to disclose, in any proceeding as defined in Section 901, the source of any information procured while so connected or employed for publication in a newspaper, magazine or other periodical publication, or for refusing to disclose any unpublished information obtained or prepared in gathering, receiving or processing of information for communication to the public.
(b)
Nor can a radio or television news reporter or other person connected with or employed by a radio or television station, or any person who has been so connected or employed, be so adjudged in contempt for refusing to disclose the source of any information procured while so connected or employed for news or news commentary purposes on radio or television, or for refusing to disclose any unpublished information obtained or prepared in gathering, receiving or processing of information for communication to the public.
(c)
As used in this section, “unpublished information” includes information not disseminated to the public by the person from whom disclosure is sought, whether or not related information has been disseminated and includes, but is not limited to, all notes, outtakes, photographs, tapes or other data of whatever sort not itself disseminated to the public through a medium of communication, whether or not published information based upon or related to such material has been disseminated.