(CNN) Oklahomans won't be able to carry guns without a permit or license after the governor vetoed a bill that would have allowed it.
In explaining her veto, Gov. Mary Fallin, a Republican, noted on May 11 that the bill would have eliminated firearms training requirements and softened background check rules.
The bill "eliminates the current ability of Oklahoma law enforcement to distinguish between those carrying guns who have been trained and vetted, and those who have not," Fallin said, according to a statement.
The legislation would have applied to gun owners at least 21 years old and to military service members or veterans who are at least 18. It wouldn't have allowed anyone to take a gun into places where state law already prohibited them.
The National Rifle Association slammed Fallin for the veto, tweeting in the wake of a May shooting in Oklahoma City its mantra that "the best way to stop a bad guy with a gun is a good guy with a gun."
The Oklahoma bill was similar to so-called constitutional carry laws in 12 other states -- Alaska, Arizona, Idaho, Kansas, Maine, Mississippi, Missouri, New Hampshire, North Dakota, Vermont, West Virginia and Wyoming -- where residents are free to carry guns without permits or licenses, according to the NRA's Institute for Legislative Action and the Giffords Law Center To Prevent Gun Violence.
Oklahoma state Sen. Nathan Dahm, a Republican who sponsored the bill, said forcing gun owners to secure permits and licenses infringes upon their Second Amendment rights.
"This is the only right that we require people to pre-emptively go and do a background check, go through the fingerprinting process, the licensing process, jump through all those hoops in order to exercise their constitutional protective right, and the Second Amendment is the one right that says 'shall not be infringed,' " Dahm told CNN affiliate KFOR.
Opponents offered a variety of arguments, including that the measure would hinder law enforcement officials' ability to contain criminal suspects, that it would deny the state a critical revenue source and that its vetting process was rushed, KFOR reported.
"Permitless carry is an incredibly dangerous policy that will make it easier for people with violent histories to be armed in public," said Alyson King, a volunteer with the Oklahoma chapter of Moms Demand Action for Gun Sense in America.