The problem is that you're starting from the assumption that things can be made "fair", by "punishing the offender". Consider that the legal system (which is designed to make the fairest decisions possible) takes forever and is not necessarily accurate. For starters, you need to admit the possibility that a fair resolution != convenient resolution.

A "con artist coder" registry isn't fair. It's error-prone at best and exploitable at worst. Sure, those "registries" might make you feel safer, but they don't really accomplish anything useful. (See the no-fly list, for example)

The logical thing to do (imho) would be to take the loss as a lesson and move on. (Paying the full amount only after completion sounds like the glaring lesson here. Also, getting second opinions before choosing a freelancer and having a written contract are no-brainers)