I am from the United States - anonymous and pseudonymous protections wouldn't apply to this case of slander/libel and/or criminal harassment. Anonymously outing someone against their will does not fall under the same protections that critiquing an unfair government does.

I didn't mean to imply that all anonymous talk is without protection, just that in this specific case, the defendant in question would probably have a very difficult time making a successful free speech argument.