HTTP error code 451 will signal online censorship

A new, official HTTP error code has been assigned to denote instances where governments restrict access to specific websites: 451. The number is a reference to Ray Bradbury’s dystopian novel Fahrenheit 451, which touches on the subject of censorship.

With online censorship on the rise, the Internet Engineering Steering Group (IESG) finally decided to approve the publication of the draft of a future standard that designates the 451 HTTP status code as an indication that the server is denying access to the resource as a consequence of a legal demand.

“Tim Bray brought this draft to the HTTP Working Group some time ago, because he (and many others) thought it was important to highlight online censorship,” Mark Nottingham, who chairs the IETF HTTP Working Group, explained in a blog post announcing the draft publication.

While the group initially believed that the the 403 status code (“Forbidden”) would be enough for these instances, after some sites began adopting the 451 code as an experiment, and members of the community became more vocal about their wish for such a code to be made official, the Working Group had a change of heart.

“By its nature, you can’t guarantee that all attempts to censor content will be conveniently labeled by the censor. Although 451 can be used both by network-based intermediaries (e.g., in a firewall) as well as on the origin Web server, I suspect it’s going to be used far more in the latter case, as Web sites like Github, Twitter, Facebook and Google are forced to censor content against their will in certain jurisdictions,” Nottinghampointed out.

“In some jurisdictions, I suspect that censorious governments will disallow the use of 451, to hide what they’re doing. We can’t stop that (of course), but if your government does that, it sends a strong message to you as a citizen about what their intent is. That’s worth knowing about, I think.”

The new code will also allow organizations to trawl the web for censored websites and to catalogue censorship.

A final version of the draft is expected to be open for comments soon.