Is a person who aids another in committing a crime "equally guilty" of that crime?

Generally, a person who aids another in committing a crime is " 'equally guilty' " of that crime. (People v. Lopez (2011) 198 Cal.App.4th 1106, 1118; see 31.) However, at times, an aider may be found guilty of a greater or lesser crime than the perpetrator. (See People v. McCoy (2001) 25 Cal.4th 1111, 1114-1122 (McCoy) [aider may be guilty of greater homicide offense than committed by perpetrator because of "defenses or extenuating circumstances . . . that are personal to the actual perpetrator and do not apply to the aider and abettor"].) Accordingly, "when a person, with the mental state necessary for an aider and abettor, helps or induces another to kill, that person's guilt is determined by the combined acts of all the participants as well as that person's own mens rea." (Id. at p. 1122.) Thus, if one defendant's mens rea is more culpable than his codefendant's, his "guilt may be greater even if the other might be deemed the actual perpetrator." (Ibid.)

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