It's perhaps worth pulling together what's been said above.
When your details are taken because you didn't have the right ticket, there are essentially three ways that it can pan out
- the railway either don't say anything more or let you off with a warning. This does happen, but not very often
- the railway take you to court: in court you either plead guilty or are found guilty (n.b. as above I'm assuming that you didn't have the right ticket) and you have to pay a penalty made up of a fine, court fees and costs, prosecution costs and compensation (i.e. the amount of the ticket that you should have bought)
- instead of the railway taking you to court, they allow you to 'settle out of court'. That involves paying them the cost of the ticket that you should have paid, plus an 'admin fee' of maybe £100 - £200
Our general advice here is that you should try to do what you can to get the railway to let you settle out of court, as generally this is the cheaper of the likely routes. The first thing to do is to make a note of everything that happened while you remember (what ticket you bought, how you bought it, why you bought that rather than the right ticket: what happened when you were stopped, what you said, what the railway officer said - things like that). Then wait for the railway (or their agents - as above Cross Country use a firm called Transport Investigations Limited (also known as TIL)) to write to you.
Once you've got that letter, come back to us: we'll be able to give you tips on what to say in your response. And TIL normally say they will move to prosecution so we can suggest what to say at that point as well.
One last point to add - you appear to be 17. This may work in your favour as some train companies are reluctant to prosecute people under 18 - but don't rely on it as some companies don't consider age. (dealt with in other posts while I was writing this)
