When Jeffrey Scott Pitts opened fire in a crowded liquor store off of a Georgia Highway in 2015, killing two men, Todd Scott, a civilian inside the shop, pulled out his gun and returned a volley of bullets. Pitts fled.

"I believe that if Mr Scott did not return fire at the suspect, then more of those customers would have [been] hit by a gun," County Sheriff Eric Levett said after the shooting, according to local reports. "So, in my opinion, he saved other lives in that store."

Scott's story - and others where firearms were purportedly used to thwart an attack - has been cited by many in a growing movement pushing for more people to be allowed to legally carry guns in more public places across the US.

"We're fighting for people's rights to carry the firearms and other weapons they need to defend themselves," said John Boch, the executive director of Illinois-based Guns Save Life, an organisation that vows to "defend your right to defend yourself".

Boch was just a few years out of college when then-president Bill Clinton signed into law a temporary ban on assault weapons. Boch says he saw it as an attack on the second amendment, so he "picked up the phone and called the NRA [National Rifle Association] and became a member that day".

He now works as a gun advocate and self-defence trainer.

"Let's face it, Donald Trump, and to an even greater degree his son Donald Trump Jr., is very strongly a part of the gun culture," said Boch. "Donald Trump - I'm guessing he's one of the first presidents who ever had a concealed carry permit."

A week before the election, the Trump campaign appointed Boch to a Second Amendment Coalition tasked with advising him on gun issues. It is chaired by Donald Trump Jr. and Christopher Cox, the chief lobbyist for the NRA - the largest and most influential gun lobby group in the country.

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The coalition is comprised of several NRA board members, gun manufacturers, gun rights advocates, athletes and celebrity gun enthusiasts who "support the right to carry personal protection and will defend the Second Amendment," according to a Trump campaign press release.

Priority number one for the NRA, which endorsed Trump and spent $30m on his campaign, is national concealed carry reciprocity. Trump supports the policy.

Many states require gun owners to obtain permits to carry a concealed weapon, with varying levels of restrictiveness. Some don't require permits and allow any gun owner who meets an age restriction to carry guns - so-called permitless states.

If passed, the controversial law would mean every town, city, and jurisdiction would have to honour the gun laws of the most permissive states with regards to gun owners from those states.

Opponents, including elected officials, gun control groups, and an association that represents police chiefs from the 50 largest cities in the US, say the legislation would undermine laws that make the public safer.

But gun rights advocates say, as in the case of Todd Scott in 2015, that more civilians with guns would mean that more people would be equipped to fight against gun violence.

"We're going to allow Americans to defend themselves with a lot less hoops they'll have to jump through to exercise their Second Amendment rights," said Boch.

"[No other president] has ever had a coalition that was tasked with unwinding gun control from the last 100-plus years and restoring the Second Amendment to what it was originally written, back to approaching 230, 240 years ago," Boch said. "I don't know of any administration that has respected the Second Amendment, not in the last century, certainly not into this century, until we've had Donald Trump here. And it's amazing, the change."

Versions of the legislation to establish national concealed carry reciprocity have been separately introduced in both the House and the Senate.

Unwinding gun control

During the campaign, Trump vowed to fulfil a laundry list of gun rights proponents' wishes, including ending gun-free zones in schools and military bases and appointing a pro-Second Amendment Supreme Court justice.

Trump recently signed into law a bill repealing an Obama-era executive order which banned social security recipients from owning guns if deemed mentally incapable of handling their own finances.

A second bill, which repeals a federal gun ownership ban on veterans who are found to be incapable of handling their own finances, recently passed the House.

It's a trend pro-gun groups hope will continue.

"We hope that President Trump will uphold his promises and do what New Jersey politicians won't," said Alexander Roubian, the president of the New Jersey Second Amendment Society, referring to national reciprocity. "Being able to defend yourself is a natural, human right, which has been codified by the United States' Constitution."

A 2008 Supreme Court decision reinforced Americans' right to own guns, but acknowledged that the Second Amendment is not without limits.

There have been challenges to state laws on carrying a gun in public, outside of gun-free zones. These have failed in lower federal courts and are now in appellate courts, not yet having reached the Supreme Court.

Both opponents and supporters of the policy agree that the US is currently a complex patchwork when it comes to legislating people carrying firearms. Some states honour other states' permits, others don't.

Those who carry a gun across the wrong state border, whether unwittingly or not, can face criminal weapons possession charges and stiff sentences.

"Thirty years ago, most states either had no concealed carry allowed or concealed carry under strict conditions. Now, every state allows concealed carry in some form," said Robert Spitzer, the chair of Political Science at the State University of New York at Cortland.



"Starting in the mid-1980s, the NRA began to push in state legislatures to modify those laws to make it easier [to conceal carry.] Now, they're onto the federal government with national concealed carry."

About eight million people in the US had concealed carry permits in 2012, according to a Congressional Research Service report. There are about 14.5m concealed carry permits in the US currently, according to John Lott, an independent pro-gun researcher.

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A complex patchwork

In late March, North Dakota became the 12th state to do away with the permitting system altogether.

New Jersey, in contrast, is one of nine states that have strict training requirements and a policy that allows police chiefs discretion to deny a permit.

Laws in those nine states were created to prevent potentially dangerous individuals, who do not have a criminal paper trail, from carrying a gun in public, says Lindsay Nichols, a senior lawyer at the Law Center to Prevent Gun Violence.

"These states give authorities the discretion that they often use in situations where they've been repeatedly called to a house because of domestic abuse," said Nichols, "or they repeatedly encountered the person intoxicated, but they've never actually arrested the person, or the person is known around town as 'off' or someone you don't want to be walking around in public with a gun."

Other laws have been passed by state legislators to fix what gun control advocates view as weaknesses in federal regulations. One example they point to is loopholes in laws that could allow people convicted of violent misdemeanours, stalking, and misdemeanour domestic violence against a dating partner to buy guns.

A recent case of this cited by gun control groups is Esteban Santiago. He killed five people in a shooting at a Florida airport in January. Santiago had repeated contact with law enforcement in Alaska and was charged, but not yet convicted, with misdemeanour domestic abuse a year before the attack.

He was hospitalised for mental health issues after voluntarily going to an Alaskan FBI field office, but his gun was returned to him upon his release. Federal law only prohibits someone from owning a gun if they are involuntarily hospitalised for mental illness. Alaska is one of the 12 permitless states.

"This legislation, it's basically gutting our nation's laws," said Lucy McBath, whose 17-year-old son Jordan Davis was fatally shot by 47-year-old Michael Dunn in 2012. Dunn, who had a valid concealed carry permit, opened fire at Davis, who was not armed, following an argument over loud music in a Florida car park.

"I was a mother, just raising her son and working for Delta airlines. It completely changed my life, Jordan's death and the way that it happened," said McBath. "I've been enlightened to what's happening in this country."

"Had Michael Dunn not actually had a firearm, the confrontation he would have had with Jordan would have just been a verbal confrontation. It would not have escalated to anything beyond that," said McBath, who now works as the faith and outreach leader for Moms Demand Action for Gun Sense in America, which has joined with the Washington, DC-based Everytown for Gun Safety.

"We're still trying to support the rights of those law-abiding gun owners who have their concealed carry permits," said McBath. "But when you're diluting the existing gun laws, how do you determine who is a good guy with a gun and a bad guy with a gun?"

In 2012, Shannon Watts, then a stay-at-home mother, founded Moms Demand Action for Gun Sense in America, shortly after the Sandy Hook Elementary school massacre, in which 20 children and six adults were murdered.

The organisation now has chapters in all 50 states and has become a unified force advocating for gun control in every state house across the country, Watts says.

"We have become the counterweight to the gun lobby. We have an army of galvanised mothers and survivors who are going to be there every step of the way to fight their extremist agenda," said Watts. "We knew when Donald Trump won we were going to immediately be working on defence at a federal level."

That means finding out where congressmen stand on the most recent legislation, she says. The Republican-controlled Senate will need eight votes from Democrats or independents to overcome a filibuster. Several Democratic senators have supported national concealed carry reciprocity in the past.

"A lot of times, you hear the gun lobby say, [a concealed carry permit] is like a driver's licence. But the reality is, this is not anything like a driver's licence," said Watts. "There's no training. There are no test requirements. It's not verifiable. If the NRA were actually pushing something like a driver's licence, we'd be having a different conversation."

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No safety requirements

Rick Lozier, 54, has been a gun enthusiast for as long as he can remember, and often keeps a handgun on him when he travels throughout his home state of Maine.

"Mostly because I can, and it's my right," he said.

But the gun shop manager, a Trump supporter, took pause in October 2015. That's when Maine passed a law and became a permitless state.

Lozier says he's only required to give a gun buyer two safety pamphlets. The buyer does not have to undergo any other training before they can carry the gun and walk down the pavement.

"Besides [the pamphlets], they're good to go," said Lozier. "Before [the state became permitless], there was an eight to 12-hour safety training requirement. [It taught] where not to point the muzzle, don't keep your finger on the trigger, stuff like that ... I'd be more comfortable if there was some safety requirement."

Half the states in the US currently require live-fire training before granting a concealed carry permit, which some experts say is essential to develop the fine motor skills needed to properly shoot a handgun.

Many require some sort of basic safety education.

In 2016, there were 53,573 violent incidents involving guns in the US, according to the Gun Violence Archive, which collects and validates data on gun use. Guns were used defensively 1,892 times that year. The site verified 2,199 unintentional shootings during the same time. Approximately 15,000 people in the US were shot and killed in 2016.

In Illinois, Boch says he's confident the current federal standards for gun ownership are sufficient for people to conceal carry.

"It's the criminals, it's the gang members that are committing the crimes in our towns across America; it is not the concealed licensees," said Boch. "I have faith the people with concealed carry licences from Indiana [which has no safety requirements] will do just fine in New York City, without doing stupid things with their guns."

For now, Boch says he is excited to be part of what he believes will be a movement over the next four, or maybe even eight, years. He says it starts with national concealed carry reciprocity.

"I never dreamed a year ago I'd have a chance to help shape protecting the Second Amendment," said Boch, "and have a hand in landmark civil rights legislation that will affect people for generations to come."