Leading article: Chris Huhne: the untold story

Chris Huhne, the Energy and Climate Change Secretary, has dominated the headlines for three weeks now. The intensity of media interest is justified by the seriousness of the allegations against him.

It is not so much the matter of an eight-year-old alleged speeding offence. It is the allegation that he asked someone else to take his penalty points, which would be an attempt to pervert the course of justice. And there is his current denial, which, if proved false, would be the most damaging.

As we go to press, it looks as if Mr Huhne may survive, if only because of the impossibility of proving wrongdoing beyond reasonable doubt.

In all this speculation about whether Mr Huhne would keep his job, however, one consideration has been almost totally overlooked. How well has he performed in this post, so crucial to the coalition's claim to be the "greenest government ever", over the past year?

This is a pertinent question because at the very time that he has been fighting off what looks like an attempt by his estranged wife to bring him down, he has won two important victories in Cabinet committees.

Earlier this month, he persuaded the Prime Minister to commit the Government to the demanding target of cutting Britain's output of greenhouse gases by 50 per cent by 2025. Then he persuaded the Deputy Prime Minister that the Green Investment Bank, which was announced last week, would be enshrined in law and be allowed to borrow, free of Treasury control.

Both decisions were fiercely resisted by George Osborne, the Chancellor, and Mr Huhne's fellow Liberal Democrat, Vince Cable, the Business Secretary.

On cutting greenhouse gases, Mr Osborne and Mr Cable argued that there was no point in simply forcing energy-intensive industries to leave the country. Given the small contribution to global warming made by Britain, the main value of cuts on one country is as an example to others, which would be lost if other countries think that the price is too high.

John Cridland, the director-general of the CBI, expressed the dilemma well last week: "If we're one step ahead we can inspire, but if we're three steps ahead we're in trouble." Yet the industries that will lose out in the short term are always going to complain the loudest, to resist any step forward, and to seek to use the Business Department to defend their interests in Whitehall. Against such vested interests, a green government needs an advocate who can exert a countervailing force. Mr Huhne passes that test.

Since David Miliband first pressed for the prioritisation of climate change at Cabinet level, the green argument has been twofold. First, that Britain can set an example. Second, that the low-carbon economy is a business opportunity for this country.

That is the significance of Mr Huhne's second victory. An independent Green Investment Bank is important to the credibility of the claim that a greener economy can be a route to greater prosperity. New low-carbon technologies require investment and there is a role for the public sector in minimising market failure in this field. As ever, the Treasury is bound to resist public bodies being given the power to borrow on the open market, just as it resisted the same powers being granted to foundation hospitals. But without the power to use its £3bn budget as a way of levering in private money, the Green Investment Bank would simply be another feeble quango.

As Nick Clegg said, when he announced last week that the bank would start lending next year, it is central to the Government's ambition "to seize the opportunities of a green economy and meet the obligation of this generation to the ones that follow".

According to his admirers in the green movement, Mr Huhne has achieved more in a year than most Cabinet ministers achieve in a lifetime. That may be an overstatement. But there should be no doubt that in the battles to come – and the victories that Mr Huhne has won this month are only single engagements in a longer war – the green cause will need someone of his aggression, knowledge and persistence.

If Mr Huhne were shown to be guilty as accused, he would of course have to resign – but he would be hard to replace. He has proved himself a tenacious fighter in the bureaucratic jungle of coalition politics, for such an important cause.