The Supreme Court’s judgment today dismisses, unanimously, the appeals of the HS2 Action Alliance, Heathrow Hub Limited and Hillingdon and other local councils. They had tried judicial review to challenge the government’s plans in respect of High Speed 2, arguing that they don’t comply with two EU Directives. They lost in the High Court, and by a majority in the Court of Appeal. The Justices have ruled decisively against them – and refused to refer the case to the European Court of Justice.

The main interest in the case, for those not deeply involved with the campaign, is the constitutional point run by the councils, who argued that Parliament’s consideration of HS2 wouldn’t be a satisfactory decision-making procedure in terms of EU law. As Lord Reed put it at para. 73,

Put shortly, it is argued that the effect of (1) the whipping of the vote at second and third readings, (2) the limited opportunity which is provided by a debate in Parliament for the examination of the environmental information, and (3) the limited remit of the select committee following second reading, is to prevent effective public participation, contrary to article 6(4) of the EIA Directive.

Lord Reed’s judgment rejects this by holding that EU law does not subject Parliament to the sort of judicial scrutiny the councils wanted; and in any event, there was no indication Parliament’s procedures would be inadequate. The approach Lord Reed takes allows him to avoid the deeper constitutional waters he’d have had to swim, if the Directive meant what the councils said it did.

Interestingly, Lord Reed makes two references to judgments of the German Constitutional Court, at paras. 106 and 111, the second of these mentioning with approval a principle applied by the German court, that ECJ rulings should not be read as undermining national constitutions. German constitutional thinking is occasionally deployed by politicians in thinking about our constitutional relationship with the EU, and we may hear more about it from judges too, in future.

Lords Neuberger and Mance do address the deeper constitutional waters, in an obiter (in other words, not binding because not part of the court’s actual reasoning) passage in their joint judgment (para. 207). If EU law were held to require national judicial scrutiny of Parliament (contrary to article 9 the Bill of Rights 1689), they say

It is, putting the point at its lowest, certainly arguable (and it is for United Kingdom law and courts to determine) that there may be fundamental principles, whether contained in other constitutional instruments or recognised at common law, of which Parliament when it enacted the European Communities Act 1972 did not either contemplate or authorise the abrogation.

This is perhaps a warning shot across the bows of Advocates General and judges of the European Court of Justice: if you decide EU law overrides fundamental constitutional rules like this, we may have to qualify UK law’s acceptance of EU law, Lords Neuberger and Mance are saying. I hope their warning is heeded. It’ll be much better, and much wiser from both the UK and the EU point of view, if Lord Reed’s approach is accepted as a correct reading of EU law.

Although the Justices were unanimous on the outcome of the case, and the main issues were shared out between Lord Reed and Lord Carnwath (who dealt with an argument that a strategic environmental assessment was required before the government announced its plans), it’s interesting that no less than four of the other Justices felt the need to write their own concurring judgments.