US District Judge Robert Lasnik ruled Tuesday against a decision by the Trump administration to allow blueprints of 3D-printed guns to be shared online. Lasnik found that the administration violated federal law in allowing a Texas company to publish blueprints of this kind on their organization’s website.

Since 2013, the federal government has maintained that the Arms Export Control Act (AECA), 22 USC § 2778, “authorizes restrictions on internet publications of CAD files that allow users to create guns and their components with a 3D printer.”

At the end of 2012, Defense Distributed, a Texas-based nonprofit, posted CAD files for various weapons on its website. Following the posting, the Directorate of Defense Trade Controls (DDTC), part of the Department of State, notified Defense Distributed that the publication might have been unauthorized and in violation of AECA regulations. The DDTC reasoned that making CAD files available on the internet was a “disclosure of technical data to foreign persons” that could be considered an “export” subject to the AECA.

Defense Distributed removed the files from its website as per the government’s request but filed a number of determination requests to the DDTC, contesting the subjection of the files to export control. The DDTC failed to make a timely ruling, sparking Defense Distributed v. U.S. Dep’t of State. The case challenged the federal government’s power to regulate publication of CAD files on the internet. Defense Distributed argued that such regulation was a violation of First, Second and Fifth Amendment rights. The State Department ultimately reversed an earlier decision by the Obama administration to ban the posting of gun blueprints.

Following the decision, Lasnik issued a restraining order to ban continued free online distribution of 3D gun blueprints. In response, Defense Distribution exploited a loophole in the order. Though Lasnik’s order banned the continued free distribution of blueprints, Defense was able to sell files to individual US residents.

In his most recent decision, Lasnik called the Trump administration’s decision an “arbitrary and capricious” violation of the Administrative Procedure Act. Lasnik further acknowledged the potential threat that the blueprints could have on US foreign policy, national security, and world peace in enabling criminals, including terrorists outside of the US, to obtain firearms.