Facebook's decision comes amidst a multi-state attack on 3D-printed guns, which itself was prompted by the State Department's recent decision to drop charges against the group Defense Distributed's website DEFCAD.
DEFCAD, one of the world's most prominent distributors of 3D printed gun files, had been facing charges that it had been allowing the transfer of weapons of war overseas. While the State Department has dropped the matter, eight states have raised it, and a judge agreed to temporarily shut down the site, noting that "the balance of hardships and the public interest tip sharply" towards having the sites inoperable.
Facebook does not need the courts to act, though, and has invoked its own rules against Defense Distributed. "Sharing instructions on how to print firearms using 3D printers is not allowed under our Community Standards,” the California company said in a statement. “In line with our policies, we are removing this content from Facebook.”
DEFCAD is not the only website where one can get the blueprint for a 3D-printed gun, of course, even if they occasionally explode while in use. CodeIsFreeSpeech.com is another website which distributes blueprints for guns like Berettas, AR-15s, AR-10s, Rugers and the gun made entirely from 3D printing, the Liberator. Facebook's ban appears to be targeting the site and those like it.