Utah law is instructive.
Utah Code Ann. 76-2-202 (1999), provides: Every person, acting with the mental state required for the commission of an offense who directly commits the offense, who solicits, requests, commands, encourages, or intentionally aids another person to engage in conduct which constitutes an offense shall be criminally liable as a party for such conduct.
As with any other crime, the State must prove the elements of accomplice liability beyond a reasonable doubt. See State v. Lopes, 1999 UT 24,11, 980 P.2d 191; State v. Labrum, 959 P.2d 120, 123 (Utah Ct. App. 1998). To encourage others to take criminal action requires some form of active behavior, or at least verbalization, by a defendant. Passive behavior, such as mere presence--even continuous presence--absent evidence that the defendant affirmatively did something to instigate, incite, embolden, or help others in committing a crime is not enough to qualify as 'encouragement' as that term is commonly used.
The case law in Utah is consistent with this definition: ''Mere presence, or even prior knowledge, does not make one an accomplice'' to a crime absent evidence showing--beyond a reasonable doubt--that defendant 'advise[d], instigate[d], encourage[d], or assist[ed] in ...