PEN §243.5: (a) When a person commits an assault or battery on school property during hours when school activities are being conducted, a peace officer may, without a warrant, notwithstanding paragraph (2) or (3)

(a) When a person commits an assault or battery on school property during hours when school activities are being conducted, a peace officer may, without a warrant, notwithstanding paragraph (2) or (3) of subdivision (a) of Section 836, arrest the person who commits the assault or battery: (1) Whenever the person has committed the assault or battery, although not in the peace officer’s presence. (2) Whenever the peace officer has reasonable cause to believe that the person to be arrested has committed the assault or battery, whether or not it has in fact been committed. (b) “School,” as used in this section, means any elementary school, junior high school, four-year high school, senior high school, adult school or any branch thereof, opportunity school, continuation high school, regional occupational center, evening high school, technical school, or community college.