Alan Pollock, an investment banker, was hailed a hero for tackling alleged ticketless student Sam Main.
But Pollock, 34, a married father-of-three, could now end up with a criminal conviction after Main, a 19-year-old student, made an official complaint to police.
The YouTube footage shows the teenager being thrown off a train by a fed-up Pollock on the ScotRail service between Edinburgh and Perth.

It begins when a conductor is told the teenager doesn’t have a ticket and tells the driver of the train to stop until the youngster gets off. When the student refuses a shouting match ensues until a passenger, later referred to as ‘the big man’ leaps to his feet and frogmarches him off the train – and keeps pushing him off when he repeatedly tries to re-board the service.

Mobile phone footage posted to YouTube, entitled ‘Scotrail No Ticket’, show the incident unfold. It was posted three days ago and has already been viewed almost 500,000 times.

Main, who studies surveying at university, has since publicly defended his actions after being tracked down by a local newspaper. He claims he was the victim of manhandling, as pictures of him with grazes over his cheeks have emerged.
He said last night: “I had been out celebrating after an exam and I was half asleep on the train.
“I did have a ticket but I must have handed over the wrong one to the conductor. The next thing I know this big guy is manhandling me to the door and throwing me off.
“I couldn’t believe it when the footage turned up on YouTube.”

Sam was visited by officers at his home in Falkirk yesterday after the video emerged showing burly Pollock throwing him head first onto a train platform. A friend of Sam’s said: “The transport police traced Sam to his house and interviewed him. During the visit, Sam decided he would like to make an official police complaint.”

In the YouTube clip, the white-haired ScotRail worker tells the youth: “I’ll sit here all night pal. I’m getting paid for this but they (the passengers) will start moaning.” The video continues with the lad protesting his innocence and claiming that he showed the ScotRail employee his “f*****g ticket” while a group of stunned young children sit close by with their furious mother.
But the conductor adds: “No you have not. Stop swearing.”
The youth produces a single ticket that allows travel in the opposite direction.
The conductor repeats his previous threat telling the youth: “No you are off, we will sit here all night. Why should they pay and not you?” It is at this point that a tall, heavyset passenger gets up, approaches the pair and asks “Is there a problem here?” before declaring “No problem – right you, off”. He then grabs the lad by the scruff of his neck and bundles him off the train, trying not to clatter into other passengers. The teenager tries unsuccessfully a couple of times to barge his way back on to get his belongings, not realising they’d also been tossed off. One woman is heard saying: “There’s no need for that” and the doors close.  As the large man heads back to his seat the carriage erupts into applause and one passenger is clearly heard saying “Cheers, big man”.

Last night, the surveying student’s flower salesman dad Lenny, 43, said Pollock had no right to do what he did, adding: “This big guy has basically thrown him head first on to the platform. “Sam’s landed on his face and has a big graze. He’s tried to get back in the carriage to get his bag. He’s diabetic and all his things were in that bag – his medication, his university notes, his money, his mobile phone and his ipod. But he’s been thrown off again. This man has to be charged and have his day in court.He had no right to do what he did. If I was him, I’d expect to be charged.”

Sam’s uncle, who asked not to be named, claimed Sam did have a ticket, but it was the wrong one. He said Sam went to the railway station at Polmont at 8am to buy a return ticket, but was told two singles would be cheaper as he planned to return off peak. He said: “He was sitting on the train when he noticed both tickets were for Polmont to Edinburgh Park, but he decided to concentrate on his exam and explain the mix-up to the inspector on the train home. “After his exam he went out for a few drinks. He got on the train and everyone’s seen the video, but he’s no fare dodger, he was just sold the wrong ticket and the inspector’s decided he’s off at Linlithgow. The big guy’s got no right to get involved, and Sam’s face is cut up.”

Ian Hems, 27, an IT teacher who filmed the incident, said: “The big man said, ‘if I end up in jail because of this, you’ve got to come and bring me a bag of pickled onion Monster Munchin prison.’ That’s pretty much all he said.

A ScotRail spokesman said: “While we welcome the public’s support of our zero-tolerance stance on anti-social behaviour, our staff are trained in conflict management and we do not expect members of the public to take matters into their own hands. We are investigating the incident, which appears to show a person travelling without a valid ticket, refusing to pay for the journey, and swearing at a staff member in full view of customers.”