Today, the House of Lords began to scrutinise the Internal Market Bill. Its dry title camouflages its incendiary content: the proposal that the Government should be given the power to breach international law and rip up the Withdrawal Treaty and Northern Irish Protocol, subject to Parliamentary approval. 

We can debate ad infinitum why ministers decided on this course of action. Had they not properly understood the treaty before the Prime Minister signed it? Or had they understood its implications full well, but always secretly plotted to rip it up? Or is this simply a negotiating ploy? If so, that seems unwise. Telling the EU we may welch on a deal we agreed and signed (supposedly in good faith) under a year ago, while trying to negotiate a trade deal with them, was always bound to erode trust and inflame passions.

Debating how we got here is interesting, but it does not address the core question: should the government be supported?

The government’s argument is that, if the EU is intransigent in the implementation of rules governing trade within the United Kingdom, this may lead to Northern Ireland being split off from Great Britain. Therefore the government should have the power to tear up the treaty.

This argument implies these issues are new, and have only just emerged. The reverse is the case. They have been debated, and been the subject of negotiation for years. It is precisely thanks to the impact of Brexit on the island of Ireland that the negotiations have been so tortuous; and why the treaty contains mechanisms to deal with these issues.

Consequently, if at some point in future the government disagrees on how the Irish protocol is to be implemented, ministers should exhaust the dispute resolution process contained in the treaty. They should not be asking Parliament to load a revolver and put it on the negotiating table now.

Ministers may claim that Parliament’s approval would be needed before the government could rip up the deal (the Parliamentary lock), and therefore there is nothing to worry about. Two points suggest otherwise. First, the Parliamentary lock was not in the first draft of the Bill, but was created to appease Conservative MPs. If Ministers had had their way, there would be no lock – which says a lot about their mindset and intent. Furthermore, there is a strong case that merely putting the current piece of legislation onto the statute book would breach international law.

To quote the Bingham Centre for the Rule of Law:

“Deferring the coming into force of these provisions pending a further resolution of the House of Commons does not diminish the Government’s breach of the good faith obligation in Article 5, by seeking powers which make the attainment of the objective of the Withdrawal Agreement more difficult, nor Parliament’s complicity in that breach if it passes the Bill containing those clauses. The Bill will also still amount to a breach of the Article 4 obligation on enactment, because the protection for the direct effect and supremacy of rights in the Withdrawal Agreement will then be vulnerable to defeasance by a resolution of the House of Commons, which is a weaker protection than that which the UK undertook to provide in Article 4 (and did provide in s. 7A of the EU (Withdrawal) Act 2018, as inserted by the EU (Withdrawal Agreement) Act).”

I certainly do not want to see the unity of our nation undermined. But nor do I want to see the government trample on the rule of law. Our nation, its stability and democratic process, relies on the rule of law. Likewise, our relations with foreign countries are governed by rules and processes designed to maintain peace and underpin prosperity. So I agree that “the rules-based international order which we uphold in Global Britain is an overwhelming benefit for the world as a whole” – to quote Boris Johnson.

Some of the Government’s supporters try to frame criticism of the government’s approach as “typical Bremoaner”. But this is not a Leave versus Remain debate. Michael Howard voted to Leave and opposes the Government’s approach. Yes, I voted to Remain. But I have always said that we must honour the result, deal or no deal. I have always thought that, if the EU demanded we remain in lock step with their approach to “level playing field” issues – like employment or the environment – that would make a mockery of Brexit, and should be rejected.

Consequently, I have always argued that we must have the ability to walk away from the negotiations – which is why last year’s General Election was the only way to break the Parliamentary deadlock and get Brexit done. As the negotiations approach the hour of reckoning, my view has not changed.

This debate is about our approach to public life; how we think about our place in the world – whether it still matters that Britain’s word is its bond; and, above all, whether we think the rule of law is non-negotiable. As someone who wants to support the government, I regret having to choose between party and principle – but principle wins every time.

 Lord Bridges is a former Brexit minister.