If the government didn't have a law, you wouldn't be able to sue
https://www.popehat.com/2016/06/11/hello-youve-been-referred...
"If you said something like "the First Amendment only stops the government from censoring you so it doesn't apply to this civil case, which is one individual suing another.""
It’s just a civil offense for which you can be sued. So I think the language of the first amendment (the government shall pass no laws…) still stands true.