Legal Q re: the sharing of personal information

I have a friend (no, seriously) who called me tonight drunk (umm… I had a friend; I hate whiny drunk people) and crying because her boyfriend apparently cheated on her. Among her incoherent ranting, she shared her brilliant plan with me which included harassing this girl via the internet by posting the girl’s cell number on, I don’t know, dating sites and craigslist or whatever.

My first thought was "Oh no, she’ll have to change her number. You’re so bad ass… :rolleyes: " but then I told her “You can’t do that.” And now I’m not so sure she can’t do it. Would posting this girl’s picture/phone number/whatever be illegal? What if it was someone’s SSN, bank account numbers, etc.? What if instead of making a fake personal ad, she posted something defaming like “This girl is a homewrecking whore.” or whatever?

The truth is she isn’t going to do any of it anyway (she breaks up and gets back together with this shitbag all the time and, now that I’m thinking of it, she didn’t actually assign any blame at all to HIM but the girl is, naturally, a morally bankrupt slut) but now I’m curious.

I’m not sure, but such actions could carry civil liabilities, if not legal ones. Your friends life could get very difficult if she pursues this.