I recently came upon a IETF draft that was published a few weeks ago.
451 Unavailable For Legal Reasons
This status code indicates that the server is subject to legal
restrictions which prevent it servicing the request.
Since such restrictions typically apply to all operators in a legal
jurisdiction, the server in question may or may not be an origin
server. The restrictions typically most directly affect the
operations of ISPs and search engines.
Responses using this status code SHOULD include an explanation, in
the response body, of the details of the legal restriction; which
legal authority is imposing it, and what class of resources it
I think this a great idea, this supports the open concept of the internet. Although it should never have to be used 🙁