So, has anyone reported this to the police?
PE, maybe you could encourage your wife to report it. This may be a way to help her see the inaction of the elders. Make her see her 'community responsibility' to simply report what she has heard, and let the police do the investigating. It may not be true, or there may be some more to the story...but either way, it is the job of the police to investigate these tings...NOT some group of internal elders.
Sorry...EDIT: I see you wrote that he was arrested. OK. sorry... Well, that is good to see