Looking at the facts? What a radical idea!

When major companies welcome with open arms an intrusive investigation that could lead to their being forcibly broken up, you know the alternative must look pretty bleak. This is where the big six energy suppliers find themselves.

It has come to such a pass that 18 months of the Competition and Markets Authority (CMA) riffling through the accounts looks preferable to more pummelling from politicians – not that there is any guarantee the former will forestall the latter.

As Ofgem on Thursday bowed to the inevitable and ordered a competition investigation into the energy sector, both industry and regulator spoke of “clearing the air”. The phrase reflects the fact Ofgem has yet to prove a market failure, while the big six insist they have nothing to hide. The hope is that a sober and, crucially, independent review of the facts will back that up.

The first task will be to establish whether the market is really “broken” and if so, how. The only undisputed argument for the referral is public distrust in the sector, a self-perpetuating condition with no obvious structural remedy.

Ofgem has sketched out some areas of concern but admits the evidence is inconclusive. The industry is happy to point out figures that tell a more positive story of thriving competition.

If it finds a problem to solve, the CMA will then consider a broad range of remedies. Breaking up the big six is the headline-grabbing option, but that is far from a foregone conclusion.

It is not only the big six who are under scrutiny, either; Ofgem’s role will also be examined. The beleaguered regulator has a patchy record when it comes to competition and the CMA may recommend changes to the way the sector is regulated.

Regulators are traditionally reluctant to make competition referrals, in part to avoid that risk. Now is a relatively good time for Ofgem to open its books, though. It has a newly appointed chairman in David Gray and chief executive in Dermot Nolan, whose reputations are not bound up in the work of their predecessors.

The process will come at a cost: upwards of £2 million for the CMA plus time and resources of Ofgem and industry. A basic investigation takes 18 months and any appeals could drag it out further.

Then there are indirect costs: the threat of structural change adds risk to the industry just as it needs to make record investment in infrastructure. It could extend the current investment hiatus and worsen the looming power capacity crunch.

Despite all this, the emerging industry consensus is: it will be worth it if it can defuse the political tensions around energy. So will it?

Labour’s reaction is not particularly encouraging on that score. Shadow energy secretary Caroline Flint insists Labour will go ahead with its promised energy price freeze if elected, not waiting for the CMA to complete its investigation. Indeed, she takes Ofgem’s assessment as further evidence the sector needs Labour’s radical reforms. The opposition seized the initiative on energy bills and is not going to give it up lightly.

Energy secretary Ed Davey’s reaction is more soothing. He offers support to get the investigation done as quickly as possible and declines to prejudge the outcome. “This is just too important for people to rely on guesses about how to fix the energy markets,” he says.

Ultimately, politicians may say what they like: any remedies recommended by the CMA are legally binding. Those recommendations will rest on facts and figures, not partisan rhetoric. In the current climate, that can only be a blessing.