The Heathrow judgment is not “undemocratic judicial activism”

Politicians do not like court decisions that get in the way of their policies. It is not that surprising, therefore, that former chancellor George Osborne has complained of “overreaching undemocratic judicial activism” following the Court of Appeal’s ruling that the government’s decision on Heathrow was unlawful.

Other supporters of a third runway at Heathrow will no doubt be similarly riled. They should not overreact. Although the ruling has major political consequences, it was not taken for remotely political reasons.

As the government begins to consider reform of the relationship between executive, legislature and judiciary, politicians need to get better at understanding that distinction.

The Court of Appeal said that the Heathrow decision was unlawful because of an act of parliament

Though the Court of Appeal’s judgment runs to 83 pages, the heart of the decision is extremely simple.

In the Planning Act 2008, parliament said “national policy statements” – like the Airports National Policy Statement (ANPS), which contained the government’s decision on Heathrow – must give reasons for the policy they contain. They must also (in particular) “include an explanation of how the policy set out in the statement takes account of Government policy relating to the mitigation of, and adaptation to, climate change”.

The Court of Appeal found that the ANPS did not explain how government policy on climate change had been taken into account. That was because it did not explain how ministers had taken into account their commitment to the Paris Agreement, which laid down an aim to limit global temperature rises this century to “well below” two degrees Celsius above pre-industrial levels.

That agreement, the court said, was clearly part of government policy by the time of the ANPS, as shown by the government’s ratification of the agreement and several statements by government ministers.

The statement did explain that ministers had taken into account domestic targets, but that these were less ambitious than the Paris Agreement. The statement was, therefore, unlawful.

The court has taken unusual pains to shield itself from political attack

This is a judgment with consequences. The government has said that it will not appeal to the Supreme Court (perhaps because the prime minister is a fierce opponent of Heathrow expansion), although Heathrow Airport itself has said that it will.

In any eventuality, it now looks less likely that there will be a third runway at Heathrow.

Judgments with political consequences have also attracted political attacks recently. In particular, the Miller/Cherry judgment last year, which ruled that Boris Johnson’s prorogation of parliament was unlawful, kickstarted a conversation in Westminster about whether the judiciary needs ‘reining in’.

That decision was at least novel in its reasoning. The Heathrow decision is not. The court is clearly desperate for politicians and the wider public to understand that it is not going anywhere near the question of whether Heathrow expansion is a good or bad idea in itself. It is instead a matter of process. The court made clear it was not saying, for example, that a new runway at Heathrow is unlawful. It could be lawful – if the government reached its decision in the way required by parliament.

The court also made clear that it was not even saying that the government’s airport policy must conform with its policy on climate change. Again, it could be lawful without so conforming, if the government explained how it had taken that policy into account.

In its judgment, the court also anticipated George Osborne’s criticism that parliament voted for the ANPS, so the judges should leave off. But that vote was on a motion, not a law, and did not change the planning requirements for the policy.

Advocates for Heathrow expansion will, of course, be looking for someone to blame for their setback. They should not blame the court.