Governor Dannel Malloy released a statement following the federal judge's decision saying, "The court's decision to grant a temporary restraining order to prevent the public release of blueprints for making homemade undetectable and untraceable plastic guns is the right one".
He said it was a case of free speech and not about guns.
The lawsuit challenges the outcome of a 2015 case that began in 2013 when Wilson, head of the nonprofit Defense Distributed, was found to have violated a federal law known as International Traffic in Arms Regulations (ITAR), after publishing downloadable plans for 3D-printed guns online.
The gun plans were pulled from the internet in 2013 by order of the U.S. State Department under global gun trafficking laws.
"I am thankful and relieved Judge Lasnik put a nationwide stop to the Trump Administration's risky decision to allow downloadable, 3D-printed ghost guns to be distributed online", Washington State Attorney General Bob Ferguson said.
Trump spokesman Hogan Gidley made much the same point, saying the administration supports the law against wholly plastic guns, including those made with a 3D printer. Now, Wilson says he wants his website to become the Wikipedia of downloadable weapons.
That prospect has startled gun control advocates, who say it could worsen the epidemic of gun violence in the US and make it easier for terrorists to gain access to a raft of deadly firearms.
The rise of 3D-printed guns could provoke a new era of "untraceable" weapons - and gun reform advocates are scrambling to figure out what to do.
Washington Attorney General Bob Ferguson filed the lawsuit Tuesday jointly with the AGs of Connecticut, Maryland, New Jersey, New York, Oregon, Massachusetts, Pennsylvania, and the District of Columbia. A lawyer for the company said he doesn't know how many blueprints have been downloaded since then.
Lawmakers say that the 3D printable guns are unsafe because they are unregistered and can be undetectable by metal detectors because they are made from plastic. He said on Twitter he was looking into the idea of a company providing plans to the public for printing guns, and he said it "doesn't seem to make much sense!".
People can use the blueprints to manufacture plastic guns using a 3D printer. President Donald Trump also questioned whether his administration should have agreed to allow the plans to be posted online.
In late June, the federal government reached a settlement with the company to allow it to resume posting the designs. "It has also remained illegal for prohibited persons to build firearms with 3D printers or by any other means as well".
Wilson has argued that the restriction on his company violates its First Amendment rights.