I think I may have made myself unclear. I'm not saying you don't have the right to ban someone from accessing your server. Of course you do.
I support the right of a site owner to try to prevent a person from accessing his site. But I don't support the right to make it illegal for someone to access this person's site if he's making it publicly available.
I don't support the right to make it illegal for someone to access this person's site if he's making it publicly available.
Even if I've sent the person a C&D letter? Accessing someone's site after they've explicitly given you legal notice not to is basically the online equivalent of trespassing.
I support the right of a site owner to try to prevent a person from accessing his site. But I don't support the right to make it illegal for someone to access this person's site if he's making it publicly available.