Possible New HTTP Status Code on the Way: 451 for Web Censorship

With all the recent crackdowns on ‘piracy’ and ‘objectionable’ content, the web is unfortunately becoming increasingly censored, something that just wasn’t done on any significant scale a few years ago. This has prompted Tim Bray, XML co-inventor and Android developer advocate to propose a new HTTP error code: 451 “Unavailable For Legal Reasons”. This error will be used to indicate that a web resource has been denied access for legal reasons and should contain an explanation for the censorship, “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 applies to.”

He then goes on to say that the error message shouldn’t indicate whether the restricted web resource actually exists or not, “The use of the 451 status code implies neither the existence nor non-existence of the resource named in the request. That is to say, it is possible that if the legal restriction were removed, a request for the resource might still not succeed.” On top of this, the error code is actually optional, so oppressive regimes that don’t want to let on that a resource has been censored can avoid disclosing this fact, potentially averting dissent from the general population. Doesn’t sound too good, does it?

So, why has Bray chosen error number 451? Because it refers to Ray Bradbury’s sci-fi novel “Farenheit 451”, which describes a dystopian future in which book burnings and the censorship of unacceptable material is routine – very appropriate we think and a sad reflection on the state of censorship today. Bray has made the proposal as an Internet Draft, submitted to the Internet Engineering Task Force (IETF) who set the technical standards for operation of the internet. Whether or not it becomes incorporated into the HTTP standard remains to be seen.