The ministerial code: what it demands and who enforces it

On paper the ministerial code is the closest thing Britain has to a contract of employment for its most powerful people. It runs to some thirty pages, opens with the seven Nolan principles of public life, and tells ministers they must not knowingly mislead Parliament, must declare and resolve conflicts of interest, must not use government resources for party ends, must record gifts and hospitality above £140, and must treat civil servants with courtesy. It reads like a rulebook. It functions as something much softer: a convention whose only working enforcement mechanism is the political self-interest of the prime minister of the day.

The document's history explains its character. It began as Questions of Procedure for Ministers, an internal Cabinet Office circular that prime ministers from Attlee onwards treated as private housekeeping; John Major published it in 1992, and Tony Blair renamed it the Ministerial Code in 1997. Nothing in that lineage involved Parliament. The code is issued personally by each incoming prime minister, who may rewrite it without a vote, a debate or even an announcement. Boris Johnson's 2022 revision quietly added lesser sanctions, such as apologies and lost salary, to what had previously been a resignation-or-nothing framework, and Keir Starmer's 2024 reissue restructured the document again and merged ministers' gift declarations into a single register published by the Cabinet Office. Each version binds ministers exactly as firmly as its author wishes.

The sharpest clause is the one about honesty in the Commons. Ministers who knowingly mislead Parliament, the code says, will be expected to offer their resignation. Amber Rudd resigned as home secretary in 2018 after inadvertently misleading a select committee about deportation targets, an outcome stricter than the text demanded. Other ministers have survived findings that would seem to sit squarely within the same words. The variable was never the wording; it was whether the prime minister of the moment judged the minister worth spending capital on.

The adviser who cannot decide anything

Since 2006 there has been an Independent Adviser on Ministers' Interests, a post created after repeated scandals to give investigations a person of standing rather than an anonymous official. The adviser scrutinises ministers' declared interests twice a year and investigates alleged breaches. For most of the post's existence the adviser could not even open an investigation without the prime minister's permission; Starmer's 2024 code finally allowed the adviser to initiate inquiries independently. What no version has granted is the power to impose a sanction. The adviser finds facts and offers a judgement; the prime minister decides what, if anything, follows.

The Priti Patel case in 2020 showed the gap between finding and consequence at its widest. Sir Alex Allan, then the adviser, concluded that the home secretary's conduct towards officials had amounted to behaviour that could be described as bullying, a breach of the code on its plain terms. Johnson declared that the code had not been broken. Allan resigned; Patel stayed. His successor, Lord Geidt, lasted barely a year before resigning in June 2022, saying he had been put in an impossible position over a proposed breach of international trade obligations. Two independent advisers walking out inside eighteen months is a fair measure of how much independence the post actually carries.

Why the courts stay out of it

The obvious remedy, litigation, is largely closed. When the FDA union sought judicial review of Johnson's decision on Patel, the High Court in 2021 accepted that parts of the question were justiciable but declined to overturn the prime minister's conclusion, treating the code as a political document whose application belongs to the political sphere. The Committee on Standards in Public Life has recommended putting the code and the adviser on a statutory footing; successive governments have declined, and it is easy to see why a prime minister would.

None of this makes the code worthless. It sets the vocabulary in which ministerial scandals are fought, gives opposition parties and select committees a fixed standard to quote, and creates the paper trail of registers and declarations that journalists mine. But its enforcement runs through a single calculation in Downing Street: is defending this minister more expensive than losing them? When the answer is yes, the code is invoked and a career ends. When the answer is no, an identical breach produces a statement of full confidence. The rulebook is genuine enough, but the referee is also captain of one of the teams.