The president of the Supreme Court has called on the Government to provide greater clarity over the role of the European Court of Justice after Brexit.
Lord Neuberger said it would be “unfair” to blame judges for making the law “when Parliament has failed to do so”.
Ministers have made clear that the top European court’s jurisdiction will end after the UK leaves the European Union.
But they have also said that UK courts should continue to interpret European Court of Justice (ECJ) case law around legislation derived from the European Union, on issues such as workers’ rights.
Lord Neuberger, who stands down as Supreme Court president next month, told the BBC: “If [the Government] doesn’t express clearly what the judges should do about decisions of the ECJ after Brexit, or indeed any other topic after Brexit, then the judges will simply have to do their best.
“But to blame the judges for making the law when parliament has failed to do so would be unfair,” he added.
The Government’s Repeal Bill says no UK court will need to have regard to decisions of the ECJ post-Brexit, but may do so if it considers it appropriate.
Lord Neuberger said all judges “would hope and expect Parliament to spell out how the judges would approach that sort of issue after Brexit, and to spell it out in a statute”.
He said he was more concerned about rulings the ECJ made after Brexit, adding: “If the UK Parliament says we should take into account decisions of the ECJ then we will do so.
“If it says we shouldn’t then we won’t. Basically we will do what the statute says.”
A government spokesman said: “We have been clear that as we leave the EU, the direct jurisdiction of the European Court of Justice in the UK must come to an end.
“However, we want to provide maximum certainty so the Repeal Bill will ensure that for future cases, UK courts continue to interpret EU-derived law using the Court of Justice of the European Union’s case law, as it exists on the day we leave the EU.”
Conservative former environment secretary Owen Paterson, a prominent Brexiteer, told BBC Radio 4’s Today programme there was a role for a UK body with specialist British lawyers to adjudicate on the interpretation of EU law.
“You cannot leave the judges flapping around without clear guidance and I would suggest we set up our own body which would parallel and mirror and be in symmetry with the ECJ,” he said.
“There must be a recognition that the ECJ does not have a remit to tell UK citizens what to do.”
Tory MP Dominic Grieve, a former attorney general, said the Repeal Bill was “very unclear” about the future relationship between British and European courts.
He told Today: “The point that Lord Neuberger is making is that that leaves a very wide measure of discretion to our own judiciary, and what he’s saying is there’s no point in those circumstances turning round at some subsequent point and saying ‘well, the judges are interpreting this in a way that is causing us, for example, difficulties’.”
Lib Dem Brexit spokesperson Tom Brake said: “Judges have already been branded ‘enemies of the people’ for daring to challenge Theresa May’s plans to force through an extreme Brexit with no accountability.
“Now the Government’s inability to set out clearly how, whether or when ECJ rulings should be taken into account risks leaving judges in the firing line yet again.
“The Government must provide greater clarity in the Repeal Bill over the role the ECJ will play post-Brexit.
“We must not let the Conservatives’ obsession with ending the jurisdiction of the ECJ lead to a chaotic Brexit that would maximise damage to British jobs and families.
“That should include abiding by ECJ rulings when this is required to ensure free trade with the EU and continued cooperation against crime and terrorism.”