Does section 31 of the California Criminal Code permit an aider and abettor to be convicted of a lesser crime or lesser degree of crime than the ultimate crime committed by the perpetrator?

The issue raised in this appeal is whether, as to crimes committed beyond that originally contemplated, section 31 permits an aider and abettor to be convicted of a lesser crime or lesser degree of crime than the ultimate offense committed by the perpetrator. Stated another way, when the perpetrator commits a crime other than that contemplated by the aider and abettor, does the aider and abettor's liability for "any crime so committed" ( 31) extend only to the ultimate offense committed by the perpetrator or does it encompass necessarily included crimes within the offense committed? (See People v. Geiger (1984) 35 Cal.3d 510, 517, fn. 4, 199 Cal.Rptr. 45, 674 P.2d 1303 [an offense is necessarily included in the charged offense if under the statutory definition of the charged offense it cannot be committed without committing the lesser offense, or if the charging allegations of the accusatory pleading include language describing the offense in such a way that if committed as specified the lesser offense is necessarily committed].)

To answer this question we again look first to common law as an indicator of legislative intent.