RAIL commuters who return to work this week will be justifiably angry when they purchase their new season tickets. An annual 3.2 per cent rise has been imposed from today for passengers using Scotrail services.

Across the UK the average rise is 3.4 per cent, with season tickets rising by 3.6 per cent.

In an era of sluggish (or no) real wages growth, today marks yet another blow to the living standards of millions of workers.

Yet before fed up commuters start taking it out on their local train guard, they should consider who is really to blame for the biggest fares increase in five years.

The UK rail network, although ostensibly in private hands, is one of the most regulated and controlled regimes in the country.

Whereas the bus industry – on which many more commuters rely – was entirely deregulated in 1985, to the point where anyone can buy a bus and run services along any route they wish and charge passengers whatever they want, the railways have never escaped the oversight of Whitehall. Or, in Scotland’s case, of Holyrood.

Season tickets and most other commuter tickets come under the category of “regulated fares”, which means that ministers, not train operators, decide how much can be charged for them. So why don’t ministers lower their cost? Simple, yes? No.

Running a railway is a costly business, and there is no network in the world that doesn’t require substantial injections of cash. The decision was made by the last Labour government that the cost of running the railways should be met more by fare-payers than by taxpayers. In other words, the balance was shifted towards those who directly benefit from the railways.

That a large proportion of the costs of running the railways is still met from general taxation is an acceptance that the railways benefit our economy indirectly too: even motorists benefit from the reduction in congestion thanks to workers choosing to take the train rather than the car.

But there are other political decisions taken at a UK level that also directly impact on the level of fares we pay. Since 2010, when road fuel duty was first frozen, the Treasury has been deprived of £46 billion – a figure now approaching the cost of delivering HS2. Political decisions have political consequences: if much-needed rail investment is not to come from road fuel duty or income tax, then it must come from somewhere. And if you’re a rail passenger, that “somewhere” is your wallet.

Undoubtedly, the anger and frustration felt by passengers will add impetus to demands for a wholly publicly-owned network. Yet even under such a scenario, new trains need to be purchased, new lines laid, essential repairs made.

The vital question is not whether such investment is made; rather it is who should pay for it, the tax-payer or the fare-payer?

More short term, Scottish ministers need to make sure that the fruits of the investment that is happening every day are visible – and soon – to understandably frustrated railway passengers. Because they also happen to be voters.

Tom Harris works with Cogitamus transport consultants and is a former UK railways minister.