Maybe I missed something, but JUPM's privacy policy seems to only illustrate my point:

If you use JUPM's discussion threads, you should be aware that any personally identifiable information you submit there can be read, collected, or used by other users of these forums, and could be used to send you unsolicited messages. We are not responsible for the personally identifiable information you choose to submit in these discussion threads. In order to avoid your e-mail address or other personal information from being gathered and used by others for inappropriate or harmful purposes, JUPM advises that you should be cautious about posting a real e-mail address or other personal information to newsgroups, chats, or other public forums.

Please keep in mind that whenever you voluntarily disclose personal information online - for example through e-mail, discussion lists, or elsewhere - that information can be collected and used by others. In short, if you post personal information online that is accessible to the public, you may receive unsolicited messages from other parties in return.

Certain JUPM media properties use a shopping cart feature that safeguards this information by using industry standard SSL (Secure Socket Layer) encrypted servers. SSL codes the information transferred between you and the server, rendering it unreadable to anyone trying to intercept the information. Other JUPM media properties do not use SSL and thereby do not offer a secure coded way to transfer information.

Ultimately, you are solely responsible for maintaining the secrecy of your personal information. Please be careful and responsible whenever you're online.
This guy is solely responsible for his own stupidity by providing information to other users freely.

And, with all due respect, I don't see how the ruling in your other post can muddy these waters. True, if internet usage may be as prevalent as using the phone or reading a paper, but from what I read, that ruling didn't address any issues of privacy. I would certainly not fault you for concern about turning this guy in, but I'm sticking with my Law and Order ruling.