May’s reassurances will always be vulnerable to repeal by a hardline successorby Raphael Hogarth / April 9, 2019 / Leave a comment
Politicians do not always keep their promises, and no one knows that better than a politician. It is little surprise, therefore, that Jeremy Corbyn’s Brexit team is trying to lock the government into whatever pledges No 10 makes on the Brexit deal. Corbyn is said to want to “Boris-proof” any cross-party agreement: if he cajoles May into commitments to a softer Brexit, including a customs union, then he does not want a harder Brexiteer unseating her and ripping it all up. Keir Starmer, Shadow Brexit Secretary, is reported to have told Labour MPs that any compromise agreement must be subject to a “Boris lock.”
Designing a Boris-proof Brexit will be a testing constitutional challenge. Merely shifting government policy would, of course, be nothing like enough. A new leader could simply shift it back.
Labour might, instead, demand that commitments to a customs union get written into the “political declaration,” the part of the Brexit deal that signals the direction of travel for the future relationship. This would be a moment of significant political theatre. The political declaration is, however, not binding or enforceable, so the practical impact of this step would be small. The withdrawal agreement itself is binding, but there is unlikely to be much mileage in trying to insert a permanent customs union there. The EU has said, again and again, that the withdrawal agreement is closed and cannot be reopened.
The vehicle for Boris-proofing any Brexit policy would probably, therefore, be legislation. If ever the government can secure a majority for a deal, it will bring forward a new “Withdrawal Agreement Bill” to implement the agreement in UK law. Labour could demand a clause in that bill which says that “it shall be a negotiating objective of the government to seek a customs union with the EU,” or similar.
That would be nothing like bulletproof. Though Labour may want the politics to follow the law, under the British constitution the law follows the politics. No Parliament can bind its successors. If Prime Minister Boris Johnson could rally a majority in the House of Commons to rip up the primary legislation directing his government to seek a customs union, then that would be the end of the matter. Even if today’s parliament tried some constitutional wizardry to make that harder—for instance,…