Story highlights Ryan Jerome was arrested when he tried to security-check his pistol

The former Marine has a permit for the gun in his home state, but he was visiting New York

The state requires that gun-toting visitors have a New York-issued permit

People carrying guns are arrested even though they have permits from their home states

An online campaign in support of a former U.S. Marine -- arrested for attempting to security-check his pistol while visiting the Empire State Building -- is bringing new attention and a fair amount of scrutiny to one of the nation's toughest gun-control laws.

Ryan Jerome, 28, was charged with criminal possession of his .45-caliber Ruger while visiting the famous New York landmark during a September vacation with his girlfriend. Jerome has a license to carry the weapon from his home state of Indiana, but New Yorks state gun laws do not recognize out-of-state permits.

With his case still pending, Jerome could face up to three and a half years in jail.

Jerome's attorney says its clear his client, who does not have a criminal record, wasn't attempting anything nefarious because Jerome approached security on his own to tell the guards about his weapon.

But the law prohibits anyone -- with certain exceptions such as law enforcement officers -- from carrying a firearm in the state unless that person specifically has a New York state-issued permit.

Jerome spent two days in a jail cell before he could make bail.

"I was in utter disbelief, I was in shock," said Jerome.

His arrest is one amid a series of similar instances that have some questioning whether New York state's strict gun laws, which aim to protect public safety, are unnecessarily targeting law-abiding citizens.

"We just don't believe, as I believe most don't think, that he should be prosecuted under such a stringent statute which is clearly designed to get the so-called bad guys," said Jerome's attorney, Mark Bederow.

Fellow Marines, on a website called leatherneck.com are rallying to Jerome's side and have begun a letter-writing campaign.

David Bruce says he's been sending the letters to New York City law enforcement officials.

"We're asking that Ryan Jerome's case be moved from the prosecution file to dismissed file -- it's as simple as that," Bruce said.

Jerome attempted to check New York's gun laws on his cell phone, but his lawyer says Jerome "made a mistake," when he read the information.

"Its just been a real nightmare," Jerome told CNN.

Other gun-toting tourists have also found themselves in similar situations

Tea party activist Mark Meckler, who according to the Transportation Security Administration legally checked his unloaded California-registered pistol in a locked box during a preflight check-in at New York's LaGuardia airport, was arrested at the airport in December.

Authorities say in Meckler's case, the original charge was reduced to a violation and a fine.

Last month, a Tennessee medical student was arrested at the 9/11 memorial after trying to check her gun; she will go to court in March.

The head of a prominent New York City gun-control group sympathizes with Jerome, but says the gun laws should not change.

"New York needs to send a very powerful message to gun owners, which is if you decide to have a gun, there's a lot of responsibility that comes with that," the president of the Citizens Crime Commission of New York City, Richard Aborn, told CNN, "And one of those responsibilities is knowing where and when you can carry that gun."

As for Jerome, his fate is in the hands of the Manhattan district attorney.

Its unclear what prosecutors will do with this case

"All of our laws allow prosecutors to carefully evaluate the facts and circumstances unique to each case, and exercise discretion in cases where justice dictates leniency," said Erin M. Duggan, director of communications for the district attorney's office.

She added, "New York state has enacted rational gun laws for one very simple reason: to protect everyone visiting, living, or working in New York."

Jerome is expected to be back in court in March.