The Ninth Circuit has determined that a California conviction for an inmate in possession of controlled substances (Pen. Code 4573.6) is both overbroad and indivisible with respect the substances listed in the Controlled Substances Act. “There is no dispute that section 4573.6 criminalizes controlled substances under California law that are not regulated under federal law, so the statute is overbroad.“ “We conclude that the statute is not divisible based on the plain text, state court decisions, and the contrast to convictions under the California Health and Safety Code. “
The court noted that a California state court has explicitly held that contemporaneous possession of two or more discrete controlled substances at the same location constitutes one offense under section 4573.6, demonstrating that the substances are alternative means, not alternative elements, of the offense. “The California Court of Appeal concluded that the phrase ‘any controlled substances’ described ‘a single offense irrespective of how many controlled substances are possessed, as here, at the same time and in the same place.’”
The full text of United States v. Graves can be found here: http://cdn.ca9.uscourts.gov/datastore/opinions/2019/05/30/16-50276.pdf