Back in the 1980's BBS sysops validated new users on some of the more abused dial-up BBS systems via snail mail. The person had to provide a real address in order to receive their login password - just as many systems use email addresses today. The big difference between these two mechanisms is that using snail mail has a chain of custody and implies the possibility of some kind of legal action for misuse whereas email has no real chain of custody or rarely any legal standing. So is it going to be a hoop to jump through or something more? Making a copy and mailing it isn't much better than forging a document and mailing it. Who knows whether the copy even belongs to the person in question? I'd say that if you've blocked someone who is a sockpuppet or other abuser the burden of validating such a person should be on them, not the wiki staff. At least a notary (or other public official) would have to look at an identity document - verify its validity as well as see that it indeed matches the person in question - then sign a document to that effect. This completely removes the wiki staff from the need to access the validity of a copy. No it isn't free, but that's the price a blocked user might have to pay for abusing what was freely given in the first place. :-/