Is a person who aids and abetts a crime even if someone else committed some or all of the crimes?

Section 31 provides that all persons "concerned in the commission of a crime" are principals to that crime, regardless of whether they directly commit the act constituting the crime or aid and abet in its commission. Thus, one who "aids and abets a crime is guilty of that crime even if someone else committed some or all of the criminal acts." (People v. McCoy (2001) 25 Cal.4th 1111, 1117 (McCoy).) "[A]n aider and abettor's liability for criminal conduct is of two kinds. First, an aider and abettor with the necessary mental state is guilty of the intended crime. Second, under the natural and probable consequences doctrine, an aider and abettor is guilty not only of the intended crime, but also 'for any other offense that was a "natural and probable consequence" of the crime aided and abetted.' [Citation.]" (Ibid.)