What are the elements necessary to prove a violation of section 422 of the California Penal Code?

^1. There are five elements necessary "to prove a violation of [Penal Code] section 422 ... : (1) that the defendant 'willfully threaten[ed] to commit a crime which will result in death or great bodily injury to another person,' (2) that the defendant made the threat 'with the specific intent that the statement ... is to be taken as a threat, even if there is no intent of actually carrying it out,' (3) that the threatwhich may be 'made verbally, in writing, or by means of an electronic communication device'was 'on its face and under the circumstances in which it [was] made, ... 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,' (4) that the threat actually caused the person threatened 'to be in sustained fear for his or her own safety or for his or her immediate family's safety,' and (5) that the threatened person's fear was 'reasonabl[e]' under the circumstances." (People v. Toledo (2001) 26 Cal.4th 221, 227-228.)

^2. People v. Marsden (1970) 2 Cal.3d 118.

^3. Unlabeled statutory references are to the Penal Code.

^4. Prior to trial, Harper admitted serving a prior prison term pursuant to section 667.5, subdivision (b).