In July last year, Howard Davies, chair of the Airports Commission, wrote a official letter to Lord Deben, reassuring him that Heathrow expansion would not prevent the UK meeting our legally binding climate targets. The letter explains that "carbon emissions were treated as a constraint, not an output". Or as the more cynical among us might translate this, the answer was predetermined and then numbers inserted into the model that would give the the right answer, realistic or not.

“There is nothing a government hates more than to be well informed; for it makes the process of arriving at decisions much more complicated and difficult.”

This quote from John Maynard Keynes was used in a recent editorial in the BMJ arguing that the UK’s planned new anti-lobbying clause, by muzzling scientists will jeopardise evidence informed policy making in public health. The potential impacts are just as concerning for other areas including energy policy.

In the new clause all organisations in receipt of state grants would have to agree, as a very broad legal condition, not to use public money to influence MPs or political parties, attempt to influence legislation or regulatory action, or press for the renewal of contracts and grants.

The 'Heathrow 13' who blocked the north runway at Heathrow in July 2015 to protest against the climate folly of a third runway have been told they are likely to face prison, because of the 'astronomical cost' of their actions - 25 flights cancelled. And yet the aviation sector continues to get off scott-free despite the astronomical cost of its own contribution to climate change.