James Frayne is Director of communications agency Public First and author of Meet the People, a guide to moving public opinion. The focus of this column is Theresa May’s conservatism for “ordinary working people”.

It’s rare for politicians and policymakers to think about the public first. Even in areas like health, education or transport, where services are theoretically designed to serve the needs and desires of the public, ordinary people come below apparently more important policy priorities.

And so it is we find GP surgeries open almost entirely when most people are working; schools with hugely long summer holidays that require parents to find expensive childcare; and a transport system that prioritises rail over roads, even though vastly more people drive.

Of course politicians must think about issues like doctor and teacher retention; but the fact remains that meetings in Westminster and Whitehall rarely begin with the question: what do the public want? In many ways, the mass politicisation of the civil service would be a good thing. At least those that chase votes care about what people think.

This dislocation of politicians and policymakers has been highlighted this week with the revelation that London and other cities across the country are considering the introduction of new charges on diesel cars. The Government ought to come out strongly against this.

We hear these charges will be introduced in the name of improving air quality. Diesel cars contribute to the amount of particulates and Nitrogen Dioxide in the air that cause dangerous air pollution.

Fair enough, you might think.  But just a few years ago politicians were actively encouraging drivers to switch to diesel to cut carbon dioxide emissions – all to help alleviate climate change. Politicians are in the process of executing a 180 degree change in policy in a few years.

It’s wrong to treat people in this way. You can’t encourage people to take what are described as virtuous acts, only to punish them later financially. And such a move surely risks hurting people that rely heavily on their vehicles for their work – self-employed people that drive vans and effectively run their businesses from them.

These are people that have endured a difficult recession and slow recovery. Hitting them for more cash each week will cause them financial pain at a bad time. It’s the wrong thing to do in principle, will hurt ordinary people – and will also further undermine the green movement.

Over the course of the last decade, politicians and civil servants seem to have taken every chance they can to raise (or threaten) charges in the name of environmental protection. There’s more than a risk that people think green causes are a political ruse to make them pay more in tax. This will make it impossible for the green movement to go mainstream.

There is a very strong case for Governments to get people off diesel and indeed to encourage electric vehicle and greater public transport use. Our cities would be cleaner and better. But politicians have to think about the lives of ordinary people as they make policy. They need to understand the financial demands of everyday life and also the need for people to save for the future.

Nobody should be expected to make massive financial decisions – like changing their car – with anything less than several years notice.