Documentary makers Joe Berlinger and Bruce Sinofksy provide a straightforward narrative on their highly publicized subject, which is a trial in upstate New York, where a dairy farmer was charged with murdering his own brother in the bed they shared. Was the ailing Bill Ward’s death a mercy killing, or a case of sex gone bad? Or, as many in Munnsville (pop. 499) believed, was his brother Delbert innocent altogether? The movie isn’t about the luridness of the situation so much as it is about the community of caring that grew up around Delbert and his other brothers (including Lyman Ward, pictured), who heretofore had been regarded as filthy, uneducated and possibly simple-minded outcasts (KCET Monday at 9 p.m.).