Cody Wilson, founder of Defense Distributed. (Cody Wilson)

Gun-safety activist Fred Guttenberg arrived in Washington to address the Democratic caucus on Monday, furious that Congress had failed to prevent the potential spread of 3-D-printed guns.

After a multiyear legal battle, the federal government last month entered into a settlement with Defense Distributed founder Cody Wilson, permitting him to publish his arsenal of firearm blueprints online. He intends to do so on Aug. 1. Lawmakers’ 11th-hour efforts have done nothing to halt his plans, and on Friday a federal judge denied a motion for an emergency injunction brought forward by a trio of gun-control groups.

Guttenberg, who has become a powerful voice against gun violence since his 14-year-old daughter was killed in the shooting at Marjory Stoneman Douglas High School in Parkland, Fla., told The Washington Post he was dismayed by his visit to the Hill. Five weeks have passed since the settlement was signed, yet only a handful of senators were aware of it, he said, adding that not a single House member knew either.

“I don’t know how we got to this place and no one was paying attention,” he lamented. “This is the safety of this country and its citizens who are now at risk in their offices, in courthouses and on airplanes.”

With less than a week to scuttle the settlement, Wilson has been bombarded with last-minute legal threats from lawmakers and advocacy groups.

Senate Minority Leader Charles E. Schumer (D-N.Y.) led the call to action on Saturday, warning of the dangers posed by the weapons, sometimes dubbed “ghost guns,” which are made from plastic and cannot be sensed by metal detectors.

“Ghost guns are as scary as they sound — a terrorist, someone who is mentally ill, a spousal abuser or a felon can essentially open a gun factory in their garage. No background check, no training,” he told The Post.

On Tuesday, Sen. Edward J. Markey (Mass.), joined by Sens. Bill Nelson (Fla.), Richard Blumenthal (Conn.), Chris Murphy (Conn.) and Dianne Feinstein (Calif.), all Democrats, sent a letter to Attorney General Jeff Sessions demanding that he explain the government’s decision to settle.  (The Department of Justice declined to comment for this story.) Nelson also plans to introduce a bill that would prohibit online publication of any digital file that can be downloaded or programmed to print a 3-D gun part.

Throughout the week, other lawmakers have joined the push: New Jersey’s attorney general sent Wilson a cease-and-desist order, warning that making the digital files available to New Jersey residents was a violation of New Jersey law. Rep. Ted Deutch (D-Fla.) wrote a letter Thursday co-signed by 40 members of the House and calling for a hearing before the deadline.

“Maybe when my colleagues realize that the end result is a plastic gun possibly getting through security in the Rayburn [House office] building, they’ll return to Washington and let us hold hearings on stopping this danger before it gets too far,” Deutch told The Post.

But as time runs out, it remains unclear whether the belated efforts will succeed.

“All the letters are nice, but they do nothing,” Guttenberg said. “At 12:01 on the 1st of August, it’s going to be too late.”

Wilson made the first fully 3-D-printed pistol in April 2013, when he was 25. He posted the design files online, to an unregulated file-sharing website. In a few days the site saw more than 100,000 downloads for the firearms, which would not have serial numbers and thus be impossible to trace. The federal government alleged that by uploading the weapon blueprints, which constituted an export under the International Traffic in Arms Regulations (ITAR), Wilson had violated federal law.

After years of legal fighting, the federal government stunned both Wilson and gun-control advocates with a wholesale reversal of position. On June 29 it entered into a settlement with Wilson that, in addition to fronting $40,000 for his legal fees, crafted an exemption from the ITAR regulations, allowing Wilson’s company to post 3-D firearm blueprints online for unlimited international distribution.

Wilson plans to relaunch next week.

Three organizations — the Brady Center to Prevent Gun Violence, Everytown for Gun Safety and the Giffords Law Center to Prevent Gun Violence — jumped into the fight on Thursday, filing an emergency motion for a preliminary injunction. A hearing was held on Friday before federal Judge Robert Pitman in Austin, who had sided with the government in earlier litigation.

On Friday, however, Pitman sided with Wilson, denying the groups’ motion.

Days from now, Wilson is likely to be able to post far more than basic hand guns on a searchable database.

“Once the plans are up on the Internet, it’s impossible to un-ring the bell,” said Jonathan Lowy, vice president of litigation at the Brady Center. “The genie is out of the bottle and you can’t put it back in.”

Read more:

Why Cody Wilson, the 3-D-printed gunmaker, thinks 3-D printing might not take off

Gun-control groups want to block publication of gun designs

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