Hmm, With the implementation of cannibalism this could be made very simple. Kuru, if you don't know what it is, feel free to wikipedia it for more info than I will provide. It causes shakes and uncontrollable laughing in people, it is believed to have originated from cannibalism and can be transferred via consumption of human flesh. A bandit will generally eat human flesh because face it, it is an easy meal for him if he is already killing humans, so make it visible if another player has the shakes, make their hands shake like a much much lesser version of pain in order to affect them like Kuru would. If a player chooses to not cannibalize in order to avoid getting Kuru, then they can do so and actively remain in a state where they cannot be recognized as a bandit. This way bandits still have the ability to disguise themselves if they forgo the easy meal of cannibalism, and this makes sure that a player can never be sure if they are a bandit or not, but it still allows for a better idea because face it, very few bandits aren't going to cannibalize.
