A federal judge on Monday blocked a Texas-based company from making digital blueprints for 3D-printed firearms publicly available online.

The decision effectively criminalizes publication of the 3D designs for guns, banning Defense Distributed founder Cody Wilson from posting the digital files on the internet. The legal controversy has sparked a national conversation about the implications of untraceable plastic guns and constitutional rights.

The decision, in favor of attorneys general from 19 states and the District of Columbia, stems from a lawsuit filed on July 30 against the State Department, which had agreed to let Defense Distributed publish an arsenal of firearms blueprints online in a planned settlement.

The states argued that the release of 3D printable designs threatened national security and abridged statesโ€™ ability to pass and police gun laws. On July 31, Judge Robert Lasnik of the U.S. District Court for the Western District of Washington, citing risks to public safety, granted the request of the attorneys general.

The legal battle over weapon-design files dates to 2013, when Wilson manufactured the first printed handgun. Days after Wilson made the blueprints available online, the federal government demanded that he remove the files. Wilson did, then sued the State Department. In June the federal government reversed course and entered into an agreement permitting Wilson to publish his firearm blueprints online. He intended to do so on Aug. 1.

Hours before he planned to publish, Lasnik stopped him.

Mondayโ€™s order ignored the brief filed by the Department of Justice, which accused the states of misunderstanding the terms of the State Department settlement and attempting to exceed their constitutional powers by restricting a person from sharing information with other Americans.

โ€œThis case is not about the regulation of U.S. persons who wish to utilize a 3D-printer to manufacture their own small-caliber firearms. Rather, this case concerns the Department of Stateโ€™s delegated authority to control the export of defense articles and services, or technical data related thereto, that raise military or intelligence concerns,โ€ the department wrote. โ€œThe domestic harms about which Plaintiffs are allegedly concerned are not properly regulated by the Department under current law.โ€

Still, Attorney General Jeff Sessions reiterated that it is illegal to manufacture plastic guns that are undetectable.

โ€œWe will not stand for the evasion, especially the flouting, of current law and will take action to ensure that individuals who violate the law by making plastic firearms and rendering them undetectable, will be prosecuted to the fullest extent,โ€ Sessions said in a statement on Thursday.

Wilsonโ€™s critics said his plan could put unregulated and difficult-to-detect weapons in the wrong hands.

Gun-control supporters, such as the Brady Center to Prevent Gun Violence, also argued that 3D-printed weapons โ€” which avoid layers of federal and state gun-control policies, such as permits and background checks โ€” are not โ€œtypically possessed by law-abiding citizens for lawful purposes,โ€ and, therefore, are not protected under the Second Amendment.