In a possession of marijuana for sale case, the trial court prejudicially erred by failing to instruct on the lesser included offense of simple possession of less than 28.5 grams of marijuana. After being arrested with 23 grams of marijuana packaged in numerous small bags, and $249 in mostly small bills, Walker was charged with possession of marijuana for sale (Health & Saf. Code, § 11359). At trial, he argued the marijuana was for personal use. An officer testified that the manner of possession, along with the denominations of cash possessed, were consistent with street-level marijuana sales. The trial court did not instruct on simple possession of less than 28.5 grams of marijuana (Health & Saf. Code, § 11357, subd. (b)), an infraction, because the court believed that an infraction could not be tried to a jury. The court also found Walker’s medical marijuana defense could not be used in a possession for sale case. Walker was convicted of possession of marijuana for sale and appealed. Held: Reversed. The trial court was required to instruct on simple possession of less than 28.5 grams of marijuana because it is a lesser included offense of possession of marijuana for sale, and substantial evidence supported the instruction. The trial court erred by concluding that it would be improper to try an infraction to a jury, because when an infraction charge is accompanied by a felony or misdemeanor charge, and a jury is not waived, the court may order all offenses tried together (Pen. Code, § 1042.5). In addition, when an infraction is a lesser included offense of a felony, a jury may find a defendant guilty of the lesser offense (Pen. Code, § 1159). The error was prejudicial because it was reasonably probable that at least one juror would have concluded that the marijuana was for personal use, given the dearth of evidence of sales. Further, due to the error, the trial court precluded Walker from presenting his medical marijuana defense.

Although defense counsel agreed that no lesser included offense instruction would be given, the record did not reflect a tactical reason for doing so and the error was therefore not invited. The Attorney General argued the instructional error was invited because defense counsel agreed that no lesser offense instruction would be given. However, nothing in the record reflects that counsel agreed for a tactical reason; she merely acquiesced to the trial court’s decision not to give the instruction. A trial court’s duty to correctly instruct the jury on the basic principles of law relevant to the issues “raised by the evidence in a criminal case is so important it cannot be ified by defense counsel’s negligent or mistaken failure to object to an erroneous instruction or the failure to request an appropriate instruction.” (People v. Avalos (1984) 37 Cal.3d 216, 229.)