The Trial Chamber convicted Tadic as principal and accessory for crimes against humanity and war crimes, including killings, beatings, and forced transfer, as well as participation in the attack. Tadic and the Prosecutor appealed.
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” (¶ 229)
2. “[K]nowledge that the acts performed by the aider and abettor assist the commission of a specific crime by the principal” (¶ 229)
The Appeals Chamber contrasted aiding and abetting from acting with common purpose or design. Among other requirements, “The aider and abettor is always an accessory to the crime committed by the other person, the principal” and it “no proof is required of the existence of a commonconcerted plan, let alone of the pre-existence of such a plan” (¶ 229).