U.S. Senators Martin Heinrich and Angus King introduced legislation aimed at curbing fatalities from mass shooting incidents while maintaining Second Amendment protections.

The two announced the Gas-Operated Semi-Automatic Firearms Exclusion (GOSAFE) Act during a press conference Thursday.

“Far too many Americans and communities from Lewiston, Maine to Farmington, New Mexico, have lost loved ones in mass shootings and we can’t bring back those we’ve lost,” Heinrich, a Democrat from New Mexico said. “But lawmakers can save lives through common sense gun safety measures. We can pass laws that regulate the inherently dangerous and unusually lethal firearms that mass shooters have wielded against our communities.”

The GOSAFE Act aims to regulate firearms based on the lethality of their internal mechanisms rather than on what the firearm looks like, to regulate the sale, transfer and manufacture of gas-operated semi-automatic firearms by making a list of prohibited firearms; preventing illegal modifications of legal firearms; mandating that future gas-operated designs are approved before manufacture and preventing illegal firearm self-assembly and manufacturing.

“The Go SAFE Act draws a bright line between traditional firearms used for hunting, sporting for self defense and these weapons of war that we see too often in mass shootings,” Heinrich said. “We focused on the lethality of firearms internal mechanisms, as opposed to cosmetic features that individuals or even manufacturers can easily modify.”

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ArmaLite 15 rifles, commonly called AR-15s, or other semi-automatic firearms, are commonly used in mass shootings.

The rifles are named for their original manufacturer ArmaLite which sold its rights to Colt’s Manufacturing Company in 1962.

“(These firearms are) dangerous because they use expanding gas to simultaneously fire one round and reload the next round into the chamber while staying on target,” Heinrich said.  

A semi-automatic firearm was used in the Lewiston, Maine shooting in October where 18 people were fatally shot and 13 were wounded in two locations: a bowling alley and a restaurant.

“In fact, the information that I have is that the shooter in Lewiston, Maine, had two large capacity magazines duct taped together, so that when one was depleted, he could simply flip them around and put the other magazine in place and keep shooting,” King, an Independent from Maine, said. “We had 18 deaths and a large number of wounded in a very short period of time, because of the mechanics of how that works. So that’s really what we’re focused on here.”

In May, an 18-year old gunman went on a shooting spree in Farmington killing three and injuring six. He used an AR-15 he bought the previous November.

Firearm buyback and Second Amendment protections

“Our bill also creates a voluntary buyback program to allow gun owners to turn over and receive compensation for non-transferable firearms and magazines,” Heinrich said. “This will ensure that lawful owners don’t lose the monetary value of firearms already in their possession.”

The reason for the buyback program was to prevent the firearm from ending up on the black market being sold to someone who may use it to conduct a mass shooting incident, Heinrich said.

The bill is not intended to confiscate people’s legally acquired and legally used firearms, the senators said. 

“Like a lot of Americans, and many of my constituents in New Mexico, I’m a gun owner,” Heinrich said. “Many of my best memories involved the responsible, law abiding use of firearms to fill my freezer and feed my friends and family. But I also firmly believe that our families and children should feel safe when they go to a bowling alley, when they enter the classroom, when they go to a place of worship. They shouldn’t have to live in fear that they might fall victim to the next mass shooting tragedy.”

The Second Amendment protections in the Act include protecting Americans’ right to bear arms based on a firearm’s established use for hunting, sport or self-defense, the act states.

The legislation aims to do this by including exemptions based on maximum ammunition capacity based on the firearm’s class, be it a rifle, shotgun or handgun, the act states.

The capacity has to be “permanently fixed” such that the firearm cannot allow a “detachable, high-capacity magazine” that would allow more rounds to be fired and make reloading easier, the Act states.