Appellants participated in the operation of three camps established shortly after the Serb takeover of the city of Prijedor to hold individuals suspected of sympathizing with the opposition to the takeover.
1. Acts “specifically directed to assist, encourage or lend moral support to the perpetration of a certain specific crime” with a “substantial effect upon the perpetration of the crime”
2. “[K]nowledge that the acts performed by the aider and abettor assist the commission of the specific crime of the principal” (¶ 89, citing Vasiljevic)
MENS REA: Distinguished aiding and abetting from co-perpetrators in joint criminal enterprises. In the latter, the requisite mens rea is intent to pursue a common purpose (¶ 89).