What happened next would be hard to believe, except that Fiorino audio-recorded all of it: a tense, profanity-laced, 40-minute encounter with cops who told him that what he was doing - openly carrying a gun on the city's streets - was against the law.
"Do you know you can't openly carry here in Philadelphia?" Dougherty asked, according to the YouTube clip."Yes, you can, if you have a license to carry firearms," Fiorino said. "It's Directive 137. It's your own internal directive."
The cops, department officials later admitted, were wrong. They didn't know that a person who has a license to carry a firearm can openly carry it in the city.
But the story doesn't end there. How could it?
After Fiorino posted his recordings on YouTube, they went viral. Members of pro-firearms forums on the Web took a particular interest in the incident.
The Police Department heard about the YouTube clips. A new investigation was launched, and last month the District Attorney's Office decided to charge Fiorino with reckless endangerment and disorderly conduct because, a spokeswoman said, he refused to cooperate with police.
Fiorino said he plans to sue the city whenever his criminal case is resolved.
Police spokesman Lt. Ray Evers said the department believes that Fiorino wanted to get into a confrontation with cops, that he wanted to see them lose their cool so he later could file a lawsuit.
Or, as one cop was overheard saying on the YouTube recording: "He set us the f--- up, that's what the f--- he did."
Terrified to be powerless
Fiorino, an IT worker who lives in Montgomery County, grew up in Feltonville.
A handful of his friends fell victim to random crimes over the years - a mugging here, a beatdown there, the kind of stuff that happens all the time in a big city.
It was enough to make him think about being able to protect himself if he ever ran into trouble. "It would be terrifying to me to be powerless," he said.
So, about a year ago, Fiorino said, he got a firearms license and began openly carrying his .40-caliber Glock.
"I did research for quite a few years leading up to making a decision to carry," he said. "I was ready to take on the responsibility."
His gun went with him everywhere - to the store, you name it.
After he began carrying, Fiorino said, he was stopped a handful of times by cops in Montgomery County and other parts of the state. The encounters were civil and quick, he said, and usually ended when an officer checked out his firearms license.
He also had encounters with Philadelphia cops last year near the Philadelphia Museum of Art and on South Street.
"Both times they told me what I was doing was illegal," he said. "They patted me down and said, 'We don't care what you consent to.'
"The second time, they did an official confiscation, and it took me five months to get back my gun."
It could be argued that Fiorino should have stopped openly carrying his gun because it invited police scrutiny. But that argument couldn't be more wrong, said John Pierce, co-founder of OpenCarry.org.
Pierce, of Minnesota, said his website offers information on gun rights "from a legal perspective, a public-policy perspective, not from a 'my cold, dead fingers' viewpoint."
"According to the Pennsylvania and U.S. constitutions, open carry is Mark's right," he said.
"To say he has to give up that right in order to stop being persecuted by the state, well, that doesn't sound like the America we want to live in."
Pennsylvania allows citizens to openly carry firearms across the state, but with a simple caveat: A person who carries a weapon openly in Philadelphia also must be in possession of a firearms license.
Fiorino said he was following the law on Feb. 13, when he decided to take a walk to AutoZone while he was in the Northeast, visiting his mom.
It was a nice day, warm enough for him to head out without a jacket, leaving his holstered Glock fully exposed.
Fiorino's firearms license was in his shirt pocket, he said, along with his driver's license.
Oh, and a digital recorder.
'Get down on your knees'
Fiorino was on Frankford near Placid Street when Sgt. Dougherty spotted him from his police cruiser, stopped and called out to him.
An unnerving back-and-forth started to unfold like a bizarre routine. Dougherty would bark an order, and Fiorino would make an alternative suggestion.
Fiorino offered to show Dougherty his driver's and firearms licenses. The cop told him to get on his knees.
"Excuse me?" Fiorino said.
"Get down on your knees. Just obey what I'm saying," Dougherty said.
"Sir," Fiorino replied, "I'm more than happy to stand here -"
"If you make a move, I'm going to f------ shoot you," Dougherty snapped. "I'm telling you right now, you make a move, and you're going down!"
"Is this necessary?" Fiorino said.
It went on like that for a little while, until other officers responded to Dougherty's calls for backup.
Fiorino was forced to the ground and shouted at as he tried to explain that he had a firearms license and was legally allowed to openly carry his weapon.
"You f------ come here looking for f------ problems? Where do you live?" yelled one officer.
"I'm sorry, gentlemen," Fiorino said. "If I'm under arrest, I have nothing left to say."
"F------ a------, shut the f--- up!" the cop hollered.
The cops discovered his recorder as they searched his pockets, and unleashed another string of expletives.
Fiorino said he sat handcuffed in a police wagon while the officers made numerous phone calls to supervisors, trying to find out if they could lock him up.
When they learned that they were in the wrong, they let him go.
That might have been the end of the thing, too, if it hadn't been for the recordings.
'He did it intentionally'
The weeks passed, but Fiorino couldn't stop thinking about what had happened to him on Frankford Avenue.
"They treated me like a criminal," he said.
"The organization that's supposed to be the embodiment of the law didn't even know some of the most important laws at the street level."
He decided to put the recordings on YouTube.
"I wanted people to know this is an example of what can happen if you exercise your rights and freedom in Philadelphia," he said.
Fiorino said he didn't lay a trap for the cops. He regularly carries a recorder with him in case he ever has to use his gun and then offer proof of what transpired, he said.
"I'm not trying to set anyone up," he said.
"It was a setup. He's done this kind of thing before," said Evers, the police spokesman, referring to Fiorino's encounters with authorities. "He did it intentionally, and he audiotaped it."
Evers said the department decided to take a second look at the case after learning about the recordings.
Any number of things could have gone wrong during Fiorino's confrontation with Dougherty, Evers said.
For one thing, Evers said, Fiorino could have been shot. Cops who raced to the scene could have gotten into a car accident or injured pedestrians.
Ultimately, the D.A.'s Office decided to charge Fiorino with reckless endangerment and disorderly conduct. He's scheduled for trial in July.
Fiorino's attorney, Joseph Valvo, said the move to file criminal charges against Fiorino was retaliation for his posting the recordings on YouTube.
"They're embarrassed and using creative theories to come up with charges," he said.
Up to speed
If there is a positive to Fiorino's saga, it is this: The Police Department is trying to make sure none of its officers are ever again caught not knowing basic gun laws.
"Our officers weren't up to speed [because] we never really addressed it," said Lt. Francis Healy, the department's lawyer.
"In the last several weeks, we've done a lot of training and put out a lot of information about what is allowed and what's not allowed. Right now, our officers are better-versed on the subject matter."
Healy said he emphasized the importance of officers being polite and professional if they have to stop a person who is legally carrying a firearm.
"You can use caution, but you don't need to curse them up and down and put a gun in their face," he said.
At City Hall on Saturday, about 30 gun owners staged a protest of Fiorino's recent arrest.
The protesters and cops got along fine.
"These aren't bad people," Healy said.