FUD is a perfectly valid precaution where there's reason to be fear, uncertainty, and doubt.
FUD is only a bad thing where there's no motive, precedent, and reason for those three - which is hardly the case here.
Like, "This new roommate of yours might be a killer. Sure looks like one. And who can trust a man that doesn't have a Facebook page?", is bad FUD.
But "Two ex-girfriends of this new roommate of yours have been found murdered in the woods, each a few years after they split. And I saw rope, duct tape, a set of hunting knives, plastic gloves, and a bottle of chloroform in the trunk of his car. Plus, when he got drunk he went on and on about how he likes this Dahmer tv-series. I think he might be a serial killer and you should be careful around him", is very reasonable FUD.
FWIW, I've been an ACLU member for quite some time.