There followed a four-year legal battle, with Defense Distributed joining forces with the Second Amendment Foundation - which defends the right to own guns - to sue the State Department. The largely plastic guns would be invisible to background checks and untraceable by law enforcement.
Attorney General Shapiro and his legal team, working in concert with the Governor and State Police, will continue seeking a preliminary and permanent injunction against Defense Distributed's plans to make its 3D gun files available online as the litigation continues.
Washington state Attorney General Bob Ferguson leads a group of eight states and Washington, D.C., in suing the Trump administation in case filed in federal court in Seattle. Besides Washington, attorney generals in Connecticut, Maryland, Massachusetts, New Jersey, New York, Oregon, and Pennsylvania have joined in.
Separately, 21 state attorneys general sent a letter to Attorney General Jeff Sessions and Secretary of State Mike Pompeo on Monday, saying that the State Department's decision was "deeply unsafe and could have an unprecedented impact on public safety".
In New Jersey, officials also had sought to block downloading of the plans for that state's residents by means of a cease-and-desist letter.
The National Shooting Sports Foundation, a trade association for gun manufacturers, says concerns over 3-D printable guns are overblown because criminals are unlikely to use the expensive technology to manufacture guns.
Durkan said expanding access to 3D guns would only benefit criminals and people who shouldn't have access to firearms. "Once they are out on the streets of PA, we'll never get them back".
That's what Cody Wilson, the man behind the idea, is saying on his website Defense Distributed. "My company and all Americans have the unquestioned right to share this information". "Honestly, it's kind of sad".
The Texas nonprofit, Defense Distributed, had put the plans for an AR-15 semiautomatic rifle on its website Friday, and as of Sunday, 1,000 people nationwide already had downloaded them, according to Shapiro's office.
Then, just recently, the federal government settled with Wilson, allowing his plans to move forward. In June, the government entered into what it called a voluntary settlement of the case after negotiations, and agreed to pay almost $40,000 of Wilson's legal costs.
"These downloadable guns are unregistered and very hard to detect, even with metal detectors, and will be available to anyone regardless of age, mental health or criminal history", Ferguson said in the press release.
A Bloomberg editorial argued privately made guns without serial numbers already are available legally, but the process requires "significant expertise".
According to Shapiro, the digital gun designs were downloaded over the weekend following a federal hearing in Philadelphia, which was "initiated" by the AG. The lawsuit also claims that the Trump administration is violating states' Tenth Amendment rights to regulate firearms.