A question was asked on Twitter this evening as to why, having just passed through the ticket barriers at Marylebone, a passenger's ticket was then checked on the train a few minutes later.
A perfectly reasonable question.
It got my mind racing in a number of different directions - The following are some of my thoughts on the topic, from the perspective of an ordinary honest fare paying passenger, traveling mostly with Chiltern Railways. If you a reading from the perspective of someone less scrupulous, please go elsewhere.
From a revenue protection perspective, Chiltern Railways will want to check that (a) a ticket is valid on a particular train and (b) that a ticket covering the journey is held at all.
I suspect that the barriers are not that clever and will open with any ticket that is valid from that station at roughly that time of day. That could include tickets to any one of literally hundreds of destinations, tickets that are valid only during peak periods, or even tickets valid on just one specific train.
The vast majority of passengers are honest and travel with valid tickets, some honest passengers travel on trains for which their tickets are not valid due to ticket-type restrictions, and some passengers travel dishonestly.
It is possible to buy tickets in advance, for specific trains, that can cost as little as £6 or £9 to travel between Marylebone and Birmingham. By buying an 'Advance' ticket at such bargain prices, the passenger forfeits much of the flexibility that a more expensive ticket would provide. If you have an Advance ticket for a specific train, you must travel on that train, otherwise you you can expect to have to buy a replacement full fare ticket if it is checked by a ticket inspector.
On a weekday, trains arriving into or departing from destination stations at peak times have specific ticket restrictions, meaning it is more expensive to travel at those times. Peak time restrictions do not apply on weekends or Bank Holidays.
London stations are peculiar in that a tap of an Oystercard (a smart card ticket) will make the ticket gates open. Oystercards are valid from London Marylebone, but only as far as West Ruislip or Amersham. A surprisingly large number of people travel outside of the London Travelcard zones having simply tapped in, in London. If caught, they will usually be made to buy a full ticket and will also have the problem of an unresolved (unfinished) journey on their Oystercard to contend with.
The unscrupulous passenger might buy a ticket far short of their destination, in the hope that they don't get caught. That is totally illegal and anyone who knowingly does this deserves to have the book thrown at them.
The busiest stations (Marylebone, Gerrards Cross, Beaconsfield, High Wycombe, Leamington Spa and the Birmingham Terminii) have ticket barriers, as do London Underground stations at which Chiltern Railways trains call. Banbury will have barriers installed later in 2014. As most passengers have valid tickets, staff only have to deal with the small number of exceptions. Ticket barriers have to be left open if a station is unstaffed, so they are not a complete solution.
South of Banbury, only the locomotive hauled trains (plus one other) have Train Managers on board. Other than that, surprise ticket checks are carried out on-board by a small band of roving ticket inspectors.
There are also random 'blockades' at stations, where tickets are fully checked.
North of Banbury, every train has a guard on board, so tickets will usually be checked. This extra presence is because a Driver Only Operation is only permitted between Marylebone and Banbury. DOO is not possible on the locomotive hauled trains and is not allowed on the one eight car weekday morning commuter train.
Revenue protection is all about checks and balances. A commercial decision has been taken to not have ticket inspectors on every train. However when a member of staff is on board it makes sense for them to check tickets, for the reasons I have given.
Most people welcome their tickets being checked on-board as it provides reassurance that the money they have paid is not subsidising people who have not paid the correct fare.
During the week, it is not possible to check many tickets on-board, because the trains are too full and uncomfortable. That is however an entirely different story...
So in summary:
-Ticket barriers help prevent ticketless travel and, broadly, help to enforce peak / off-peak ticket restrictions.
-On-board ticket checks help to minimise the number of people traveling with invalid tickets.
The ticket checking regime is not perfect, but I for one welcome anything that stops my fares going up unnecessarily due to people not paying the correct fares for train travel.