In the latest drama of Brexit, the British government has indicated its plans to revisit the withdrawal agreement it signed with the EU on the terms of departure. Boris Johnson’s government appears to have adopted unilateralism and a “Britain First” mentality to ensure he “gets Brexit done.”

To get an “oven-ready” Brexit signed, sealed, and delivered by the upcoming deadline on December 31, 2020, Boris Johnson is willing to commit himself to overcome the final hurdle of Brexit, even if that means breaking international law. Under the current agreed-upon terms, Northern Ireland will remain in the UK’s customs territory, with Northern Ireland being included in any future UK trade deals. However, unlike the rest of the UK, Northern Ireland will continue to adopt the EU’s Single Market regulations. Put more simply, to avoid a hard border between Northern Ireland and the Republic of Ireland, Northern Ireland will continue to adopt European levels of taxes and duties, and instead, a de facto customs border will be drawn down the Irish Sea.

The internal market bill, however, serves to override this Northern Ireland protocol. It seeks to remove Northern Ireland from these single market regulations, to sustain a joined-up market of the UK, and to ensure all four nations of the UK maintain the same standards and rules so that goods can be traded freely. In theory, this is a completely rational principle to advance. If the UK wants to negotiate trade deals with the likes of Australia and the US in a post-Brexit environment, a state with different internal rules and regulations would make these prospective deals exceedingly more complex, and therefore, could prevent the most desirable deal for Britain.

However, the Brexit withdrawal agreement is not just any agreement. It is a legally binding treaty, signed by both the European Union and the British government. Johnson’s unilateral withdrawal would break international law, undermine trust in an already strenuous relationship, and more importantly, could speed up the dissolution of the union.

Section 7 of the European Union Withdrawal Agreement Act 2020 suggests that the withdrawal agreement overrides any UK domestic law about the same issue, and therefore, cannot simply be overridden by any UK domestic law. The internal market bill inherently seeks to undermine the withdrawal agreement by placing greater power within the Westminster parliament and the cabinet. More notably, it gives UK ministers the ability to disapply UK declarations made within the withdrawal agreement. The most clear-cut example of this is it allows the secretary of state for Northern Ireland to repeal aspects of the withdrawal agreement it does not agree with to maintain the integrity of the union.

The internal market bill has provoked a backlash from Johnson’s backbench, most notably from Sajid Javid, all five former British prime ministers, as well as the speaker of the US House of Representative’s Nancy Pelosi. This is because the US played a key role in brokering the Good Friday Agreement, which brought about peace in Northern Ireland. Revisiting the withdrawal agreement may put that peace at risk.

Despite this backlash, the bill was passed in the House of Commons with a comfortable 77 vote margin, by 340 votes to 263. The main challenge now is next week’s vote on an amendment by the Conservative chair of the Justice Select Committee, Bob Neill. Neill’s amendment seeks to create a parliamentary veto on overriding the UK-EU withdrawal agreement, which will inherently undermine Britain’s international reputation.

The controversy of the bill goes beyond the legality of the issue. It gets to the heart of the fundamental question of Brexit, is it a fundamental law that is set in stone, or can it be wilfully altered by Parliament? This was exemplified by Theresa May, the main architect of much of the withdrawal agreement, when she raised the question in the House of Commons, “How can the UK ensure international partners that the UK can be trusted to abide by the legal obligations that it signs?”

May has touched on an interesting point here, not only in terms of the UK’s international obligation, but more so, the internal structure of the UK. The internal market bill more importantly will be a violation of the Sewel Convention. The Sewel Convention has been at the heart of devolution since the late 1990s. It prevents the Westminster Parliament from legislating on issues that concern the devolved assemblies without their express concern.

Theresa May’s approach to this problem was to erect Common Frameworks with the respective devolved assemblies in a post-Brexit environment. Currently, the devolved institutions are bound to comply with EU law. When the transition period ends, many nominally devolved policy areas such as environmental regulation, agriculture, fisheries, and food standards would fall completely under devolve control. This would allow for the devolved assemblies to maintain their autonomy in issues of greater concern to the national communities but would also provide a greater degree of stability when it comes to negotiating future trade deals.

The internal market bill, in this case, serves to break this promise. It forces Scotland, Wales, and Northern Ireland to follow the standards of the Westminster government to promote frictionless trade. More importantly, given that the bill is parliamentary legislation, it does not need the approval of the devolved assemblies. It seeks to transfer greater powers post-Brexit from the individual assemblies towards the cabinet ministers responsible for the nations.

All of this is strikingly familiar in a Johnson administration: breaking the law, winning campaign slogans, and disregard for the devolved nature of the union. Johnson’s attempt to strengthen the union by undermining the credibility of the union on the international stage appears paradoxical. A more important paradox, however, might be that the breakaway from the EU could result in the breakup of the UK itself.

Conor McLaughlin is a Research Analyst in the Defence and Research Engagement portfolio at Edith Cowan University.

This article is published under a Creative Commons License and can be republished with attribution.