How Trump’s Actions in the US Could Push the UK Towards Constitutional Reform

By Mika Chen, Intern at Unlock Democracy

In the past six months, the topic of UK constitutional reform has become more prominent than ever. Why? The turbulent tenure of President Donald Trump in the US has shone a spotlight on the shortcomings of constitutional checks and balances. A worrying trend has emerged, marking a decline in respect for the constitutional principles that had once been considered sacrosanct in the American political system.

Similarly, the UK - whilst not facing the same degree of constitutional erosion - has also experienced worrying signs of democratic backsliding. The traditional reliance on conventions and unwritten rules has exposed cracks in our constitutional set-up. 

This raises an important question: Could the UK's institutions be vulnerable to similar assaults that have weakened the US under Trump?

The UK is no stranger to constitutional crises. Recent events have underscored how fragile our constitutional settlement can be. A notable example is Boris Johnson’s decision to prorogue Parliament in 2019. Effectively suspending parliamentary proceedings during a critical period in the Brexit process was labelled by many as a direct violation of constitutional norms. 

The Supreme Court ruled this action to be unlawful, highlighting how the UK’s reliance on conventions, rather than codified laws, left its institutions vulnerable to political manoeuvring. Johnson’s disregard for parliamentary sovereignty and frequent tension with the judiciary raised concerns that without clearer, more formal checks and balances, the UK too could experience a decline in respect for its own constitutional framework. 

Trump is setting a precedent whereby the dismissal of ostensibly-binding provisions has now become normalised. Seeing this, UK politicians may be more likely to test the boundaries of constitutional rules themselves. 

This brazen behaviour will embolden political leaders across the world to push the democratic boundaries. The erosion of constitutional safeguards in one country can inspire similar disregard elsewhere, potentially undermining democratic norms and stability in nations already vulnerable to such shifts.

The UK’s unwritten constitution is particularly vulnerable. The "good chap" principle, which has long underpinned the country's unwritten constitution, suggests that political leaders should respect conventions, even in the absence of strict legal requirements. However, recent political developments may lead some UK politicians to feel less constrained by these conventions. 

The USA has a written constitution, but Trump’s actions show us that it is still vulnerable to executive overreach. In the UK, there is little standing between our unwritten constitution and a future rogue Prime Minister who wants to follow Trump’s example. Indeed, the apparent success of political manoeuvres that flouted constitutional principles - such as Trump’s challenge to election results and Johnson’s attempted prorogation of Parliament - may push UK leaders to believe that constitutional safeguards are, at best, flexible and, at worst, easily bypassed.

For this reason, it is essential that constitutional reform is proactively pursued in the UK. The decline in respect for democratic principles in the US, even despite the existence of a codified constitution and rigid checks and balances, highlights the need for a written constitution in the UK that establishes clear, enforceable limits on executive power. 

Unlike the current system, a codified constitution would reduce ambiguity, maximising the chance that constitutional protections are consistently upheld and making it harder for political leaders to overstep their bounds without legal consequences. It would formalise the separation of powers, creating a clearer system of checks and balances that prevents any one branch from amassing excessive power (as seen in the US under Trump). 

A written constitution would also provide a permanent safeguard for individual rights and freedoms, offering greater protection than the current laws like the Human Rights Act - which can be repealed by a simple majority in Parliament. Given the global rise of populism and political unpredictability, the UK must act now to protect its institutions and ensure the integrity of its democracy for future generations.

The effect of political polarisation

In both the United States and the UK, rising political polarisation has played a role in eroding trust in democratic institutions, pushing political leaders to test the boundaries of established rules and norms. Trump’s presidency, in particular, has showcased how polarisation can lead to a disregard for constitutional safeguards, with his populist approach appealing to those who feel alienated by the political elite and traditional systems.

In the UK, we are seeing similar trends. The growing divide between political factions has amplified frustrations with the existing constitutional framework, especially the unwritten conventions that many feel no longer serve to maintain order. 

According to a 2022 survey by The Constitution Unit, satisfaction with the way democracy works in the UK remains relatively low at only 54%, reflecting broader concerns about the political system. This dissatisfaction is fueling disillusionment, prompting voters to turn towards more unconventional and extremist parties, such as Reform UK, in search of alternatives to the current political order. In recent years UK voters have become more polarised on certain issues. A 2024 study by NatCen found that in 2011, the ideological gap between Conservative and Labour voters on immigration was 14 percentage points; by 2024, this gap had widened to 29 points.

This widening ideological gap phenomenon is one of the main drivers of constitutional disregard. My analysis found that there is a connection between polarisation and executive respect for the constitution; showing that as polarisation increases, respect for constitutional norms tends to decrease. 

Polarisation in the graph below is measured on a 0-4 scale, where 0 means political opponents generally interact in a friendly manner, and 4 means they engage with hostility. Executive respect for the constitution is also measured on a 0-4 scale; where 0 means leaders violate the constitution without consequences, and 4 means they adhere to it perfectly.

As we can see, in the US this relationship is especially pronounced, where heightened polarisation has increased alongside an erosion of constitutional checks and balances. 

Whilst the UK exhibits a weaker correlation, the trend is significant and remains concerning. These findings highlight a broader risk: as political polarisation intensifies, there may be greater challenges to upholding constitutional principles, with leaders more inclined to put partisan interests above constitutional integrity. 

The UK now stands at a crossroads, where the need for proactive constitutional reform is key. A codified constitution would provide much-needed clarity and work towards the protection of democratic principles, regardless of political shifts. With rising political polarisation accelerating the erosion of constitutional conventions, this reform is increasingly urgent - not just to address existing vulnerabilities, but also to insulate the UK’s institutions against further destabilisation.