Penal Code § 151
CHAPTER 7. Other Offenses Against Public Justice
(a) Any person who advocates the willful and unlawful killing or injuring of a peace officer, with the specific intent to cause the willful and unlawful killing or injuring of a peace officer, and such advocacy is done at a time, place, and under circumstances in which the advocacy is likely to cause the imminent willful and unlawful killing or injuring of a peace officer is guilty of (1) a misdemeanor if such advocacy does not cause the unlawful and willful killing or injuring of a peace officer, or (2) a felony if such advocacy causes the unlawful and willful killing or injuring of a peace officer.
(b) As used in this section, “advocacy” means the direct incitement of others to cause the imminent willful and unlawful killing or injuring of a peace officer, and not the mere abstract teaching of a doctrine.