CAL. PEN. CODE § 422 : California Code - Section 422

(a) Any person who willfully threatens to commit a crime which will result in death or great bodily injury to another person, with the specific intent that the statement, made verbally, in writing, or by means of an electronic communication device, is to be taken as a threat, even if there is no intent of actually carrying it out, which, on its face and under the circumstances in which it is made, is so unequivocal, unconditional, immediate, and specific as to convey to the person threatened, a gravity of purpose and an immediate prospect of execution of the threat, and thereby causes that person reasonably to be in sustained fear for his or her own safety or for his or her immediate family's safety, shall be punished by imprisonment in the county jail not to exceed one year, or by imprisonment in the state prison.

(b) For purposes of this section, "immediate family" means any spouse, whether by marriage or not, parent, child, any person related by consanguinity or affinity within the second degree, or any other person who regularly resides in the household, or who, within the prior six months, regularly resided in the household.

(c) "Electronic communication device" includes, but is not limited to, telephones, cellular telephones, computers, video recorders, fax machines, or pagers. "Electronic communication" has the same meaning as the term defined in Subsection 12 of Section 2510 of Title 18 of the United States Code.