[user104658]

My daughter's high school sent round an email about this lately. No one called a paedophile or anything like that to be fair - but "comedy" videos made using pictures of the staff from the school website.

Unless the person who did it tells someone it was them and that info is passed on, the issue is that there's really no way to find out who made the videos.

Usually they'll have told their friends of course and it gets around and then someone spills the beans. However if they just keep denying it and claim it's just a rumour that it was them, there's very little action that can be taken.