I volunteer on a heritage railway and in addition to operational roles I also do ticketing, both on the train and in the booking office. I’ll explain how this scenario works on the line I volunteer at, this may be different from how other lines do it.
The ticket inspector on the train carries a tablet which has the same point of sale system as the booking office which means we can do anything on the train that the booking office can do, including issuing tickets for online bookings. The ticket inspector can accept both cash and card payment, on the very rare occasion a ticket can’t be sold on the train the passenger will be directed to the booking office when they alight to buy their ticket there.
Every train has a ticket inspector and everything longer than a 2 car DMU has at least two ticket inspectors, someone will be along to check you’ve got a ticket or to sell you one very quickly, 99% of the time before the train reaches the next station.
I’ve only once had a passenger attempt fare evasion on my train and that was an attempt at short faring. It was a 2 car DMU with almost every seat taken, I was the only ticket inspector onboard and I started at the opposite end of the train from where they were sat which meant by the time I reached them the train had already made another station call, one of the rare occasions that happens on my line. They attempted to buy their tickets from that station call, even though nobody had boarded the train at said station, instead of where they’d actually boarded the train. They did eventually pay the correct fare so no further action was taken.
If a passenger refused to pay, they would be instructed to leave the train at the next station, regardless where that is, and if they refused to leave the train we can call the police. Us ticket inspectors would not detain a passenger. I can’t comment on the prospects of prosecution, that would be for management to determine and is entirely out of the hands of the ticketing group at the railway.
Not really fare evasion but still passengers trying to get out of spending money, on gala days we get quite a few people come up to the ticket inspectors on the train and demand a refund because the loco they were hoping for didn’t produce. In the time that I’ve been volunteering we’ve always operated the advertised traction, so when someone complains they’ve not got the loco they wanted they’re complaining about not getting something we never promised them. We don’t provide refunds in such cases as we’ve delivered what we promised them, but they can become very difficult to deal with, sometimes aggressive. I would say that is a much larger issue for heritage lines than fare evasion is. It puts some of the non-enthusiast volunteers off wanting to work galas and as non-enthusiasts make up a large percentage of our ticketing group it can make gala days difficult to operate.