The US Senate gave final approval on Monday to a bill to renew a ban against firearms that can pass undetected through metal detectors, but rejected calls to update the law in response to the advent of plastic guns made with 3D printers.
On a voice vote, the Democratic-led Senate passed the bill, which would extend for 10 years the Undetectable Firearms Act of 1988.
The Republican-led House of Representatives approved the bill last week and, like the senate, refused to pass tougher provisions opposed by the powerful gun industry.
US President Barack Obama signed the legislation into law before the ban was to expire at midnight.
Along with many fellow Democrats, Obama would prefer an updated version of the ban to close what are seen as loopholes created by new technologies, such as 3D printing, an aide said.
Senate Democrats led by Charles Schumer failed on Monday to win quick approval of a measure to require all firearms to include at least 3.7 ounces (105g) of non-removable metal essential for its operation.
Without the provision, backers say, the metal could be taken off the gun, permitting a functional weapon to pass undetected through metal detectors and X-ray machines and carried into supposedly secure areas.
Senate Republicans refused to provide the unanimous consent needed to approve the change on a legislative fast-track.
Democrats then joined Republicans in voting to extend the ban, but promised to keep pushing for tougher provisions. A key Republican said he was ready to listen.
The ban was first signed into law in 1988 by then-US president Ronald Reagan shortly after the introduction of the Austrian-made Glock firearm. Made largely of synthetic material, the Glock created a fear of undetectable weapons.
That increased with the proliferation of the underground production of plastic guns with 3D printers.
Democratic Senator Chris Murphy called for an update of the law, saying: “This isn’t science fiction anymore... Someone can make a gun in their basement.”
The gun industry favored extension of the ban, but opposed expanding it, saying the proposed modernization of the law would violate the right to bear arms and unnecessarily interfere with the legal production of firearms.
The Center for American Progress, a liberal advocacy group, called it “crucial” to extend the ban, but denounced the measure passed by congress as “deeply flawed.”
“It does nothing to address new technologies like 3D printing that could allow terrorists and other dangerous people to easily make fully functional, undetectable guns,” said Winnie Stachelberg, an executive vice president at the center.