Collective cabinet responsibility is a key constitutional convention that shapes the government of the United Kingdom. It dictates that all members of the government are jointly responsible for its policies and decisions and must publicly support them, regardless of any private reservations.

The convention is not a law but a binding rule of political conduct set out in the ministerial code. It is underpinned by three principles: confidence, unanimity and confidentiality.

Ultimately, if a minister finds they cannot publicly support a government position, they are expected to resign from their role.

Collective responsibility is considered essential for maintaining a strong and united government, ensuring it presents a clear and consistent front to parliament, the public and other states.

Collective responsibility is also central to accountability in the parliamentary system, ensuring that those who bear responsibility for explaining decisions cannot simultaneously express reservations. The government speaking with a single voice provides clarity and allows for effective scrutiny by parliament and the public.

The application and potential breaches of collective responsibility are a perennial source of controversy.

When questioned about the principle in June 1977, Labour prime minister James Callaghan stated: “I certainly think that the doctrine should apply, except in cases where I announce that it does not.”

The core principles

Collective responsibility is said to have begun under King George III as a way for the cabinet to prevent the king from playing ministers off against one another. Today it is defined by three core principles.

Confidence

A government may remain in office only for as long as it retains the confidence of the House of Commons. This confidence is presumed unless and until it is actively withdrawn through a confidence vote. While a government may be defeated on individual policy issues, this does not necessarily indicate a loss of overall confidence. By contrast, defeat on an explicit motion of no confidence signals that the commons judges the government as a whole to be unfit to govern. Collective responsibility means that a vote of ‘no confidence’ leads to the resignation of the whole government.

Unanimity

The principle of unanimity means that once a decision has been reached in a cabinet meeting, all ministers must support it in public. Whether they were involved in the discussion or not, and whether they personally agree with the outcome or not, they are bound to speak in favour of the government’s agreed position. A minister who cannot adhere to this is expected to resign.

Confidentiality

The principle of confidentiality ensures that the internal discussions through which the government reaches its decisions remain private. This allows ministers to debate issues frankly, expressing disagreement and exploring options without the fear of public exposure. This privacy is intended to help forge the unanimity required once a decision is made. Breaches of this principle through “leaks” to the media are common and can be politically damaging. Ministers found to be guilty of “leaks” are expected to resign.

Collective responsibility and the ministerial code

The ministerial code, re-issued in October 2025 by the Labour government, states: “The principle of collective responsibility applies to all government ministers.”

The code adds: “The principle of collective responsibility requires that ministers should be able to express their views frankly in the expectation that they can argue freely in private while maintaining a united front when decisions have been reached.

“This in turn requires that the privacy of opinions expressed in cabinet and ministerial committees, including in correspondence, should be maintained.”

The suspension of collective responsibility

The convention is not absolute and has been formally suspended on rare occasions to manage irreconcilable political divisions within the government, typically during referendums or coalition. This is sometimes referred to as an “agreement to differ.”

Key instances of suspension include:

2016 Brexit referendum

In January 2016, prime minister David Cameron announced that government ministers would be free to campaign for either side of the referendum on Britain’s membership of the European Union (EU).

The prime minister told MPs: “It is the nature of a referendum that it is the people not the politicians who decide. And as indicated before Christmas, there will be a clear government position, but it will be open to individual ministers to take a different personal position while remaining part of the government.”

On 11 January 2016, Cameron wrote to ministers, urging them to treat each other “with appropriate respect and courtesy” during the forthcoming referendum campaign. Cameron set out the details of his “wholly exceptional” decision to suspend collective responsibility.

After a rare Saturday cabinet meeting on 20 February 2016, following the conclusion of Cameron’s EU renegotiation, six cabinet ministers broke ranks to join the ‘Vote Leave’ campaign. This ‘gang of six’ comprised Grayling, as well as Michael Gove, the justice secretary; Iain Duncan Smith, the work and pensions secretary; John Whittingdale, the culture secretary; Theresa Villiers, the Northern Ireland secretary; and Priti Patel, the minister of state for employment (who attended cabinet).

Gove, a close political ally of Cameron, released a 1,500-word essay outlining what he called “the most difficult decision of my political life.”

2010-2015 coalition government

The Coalition Agreement between the Conservatives and Liberal Democrats set out specific areas, such as the renewal of the Trident nuclear deterrent, education funding and a proposed referendum on electoral reform.

The 2011 referendum on the alternative vote (AV) meant collective responsibility was set aside. Electoral reform was a flagship policy of the Liberal Democrats, who had long argued that first past the post (FPTP) was unfair to smaller parties.

The coalition agreement read: “We will bring forward a Referendum Bill on electoral reform, which includes provision for the introduction of the alternative vote in the event of a positive result in the referendum, as well as for the creation of fewer and more equal sized constituencies.

“We will whip both parliamentary parties in both Houses to support a simple majority referendum on the alternative vote, without prejudice to the positions parties will take during such a referendum.”

This referendum led to the incongruous political situation of the two governing parties openly campaigning against each other.

1975 EEC Referendum

In 1975, the Labour government was officially in favour of remaining in, but Harold Wilson, the prime minister, granted his ministers a rare ‘agreement to differ’. Speaking in the House of Commons in January 1975, Wilson said cabinet ministers would be “free to support and speak in favour of a different conclusion in the referendum campaign”. Of the 23 members of Wilson’s cabinet, seven did not support the government’s pro-EEC position.

It was made plain that the freedom provided to ministers did not extend to parliamentary proceedings. Eric Heffer, the minister of state for industry, was forced to resign after he fell foul of this rule, having spoken against the government position in a commons debate.

Heffer told MPs in April 1975: “I believe that the guidelines of the Common Market are as unacceptable as the guidelines on the question of ministerial discussion in the House.

“The guidelines that we need are the guidelines of the British people. I am convinced that they will vote ‘No’ in the coming referendum, and they will be right to do so.”

Notably, on 2 June 1975, europhile home secretary Roy Jenkins and eurosceptic industry secretary Tony Benn engaged each other in a BBC Panorama TV debate.

The National Government and free trade (1931/1932)

Shortly after the formation of the national Government in 1931, an “agreement to differ” was approved. Tariff policy divided the coalition government, which was split between protectionist and pro-free trade elements. Liberal ministers in the National Government were allowed to differ from the government’s policy.

In January 1932, the home secretary, Liberal MP Herbert Samuel, began a speech in parliament by referencing the doctrine of collective responsibility. He said: “The House will have an opportunity… of discussing fully the departure from the doctrine of collective responsibility which is marked by my appearance at this box this afternoon”.

Samuel argued that tariffs would tax the “food of the people”.

The official terms of the ‘agreement to differ’ were published in the Times on 23 January 1932.

It stated: “The cabinet has had before it the report of the committee on the balance of trade, and after prolonged discussion it has been found impossible to reach unanimous conclusion on the committee’s recommendations.

“The cabinet, however, is deeply impressed with the paramount importance of maintaining national unity in presence of the grave problems that now confront this country and the whole world. It has accordingly determined that some modification of usual ministerial practice is required and has decided that ministers who find themselves unable to support the conclusions arrived at by the majority of their colleagues on the subject of import duties and cognate matters are to be at liberty to express their views by speech and vote.

“The cabinet, being essentially united on all other matters of policy, believes that by this special provision it is best interpreting the will of the nation and the needs of the time.”

The agreement to differ, the first official declaration of its kind, was immensely controversial. Stanley Baldwin, a senior Conservative minister, argued that the British constitution was a “living organism”. He insisted that this was wholly beneficial to the stability of the country.

In the wake of the controversy, a no confidence motion was rejected by 438 votes to 39.

Notable resignations (collective responsibility upheld)

Howe resignation (1990)

On 1 November 1990, Geoffrey Howe resigned from his posts as deputy prime minister and leader of the House of Commons, citing fundamental disagreements with Margaret Thatcher’s stance on European integration. It came after Thatcher famously responded “No. No. No.” when considering proposals for European integration put forward by Jacques Delors, the president of the [European] commission.

In his resignation letter, addressed to the prime minister, Howe cited “the growing difference which has emerged between us on the increasingly important issue of Britain’s role in Europe.”

Cook resignation (2003)

On 17 March 2003, Robin Cook, the leader of the House of Commons and a former foreign secretary, resigned from Tony Blair’s cabinet in protest at the government’s decision to commit British troops to the invasion of Iraq. His departure marked the most high-profile protest against the conflict from within the government.

In his letter of resignation, Cook wrote: “It is 20 years ago that I first joined Labour’s shadow cabinet. It is with regret I have today resigned from its cabinet. I can’t accept collective responsibility for the decision to commit Britain now to military action in Iraq without international agreement or domestic support.”

Chequers resignations (2018)

On 8 July 2018, the secretary of state for exiting the European Union, David Davis, resigned from the cabinet. The resignation was a direct protest against the ‘Chequers plan’, a compromise agreement on the future UK-EU relationship that had been revealed to the cabinet just two days earlier by prime minister Theresa May.

In his resignation letter, Davis told the prime minister he would not be a “reluctant conscript” to the plan agreed at Chequers. He argued that “the current trend of policy and tactics” was making it “look less and less likely” that the UK would leave the customs union and single market.

Steve Baker, a junior Brexit minister, resigned alongside Davis. The following afternoon, Boris Johnson, the foreign secretary, also resigned. In his own resignation letter, Johnson claimed the Chequers plan meant the UK was “heading for a semi-Brexit” that would leave it as a “colony” of the EU.

Breaches of collective responsibility

Ministerial resignations may come following a period in which collective responsibility is perceived to have been breached.

Chequers and Brexit strains (2018/2019)

Theresa May’s cabinet inherited the divisions that characterised the 2016 Brexit referendum. Her position of relative political weakness, defined by the imperative to maintain a Remain-Leave balance in cabinet, constrained her ability to respond to perceived breaches of collective responsibility.

Her cabinet suffered from consistent leaks, which addressed the divisions over the government’s Brexit strategy.

In a letter to Conservative MPs upon the publication of the Chequers scheme, May suggested the agreement marked the moment cabinet collective responsibility would be reimposed.

The prime minister wrote: “During the EU referendum campaign collective responsibility on EU policy was temporarily suspended. As we developed our policy on Brexit I have allowed cabinet colleagues to express their individual views.

“Agreement on this proposal marks the point where that is no longer the case and collective responsibility is now fully restored.”

This statement suggested that the government had not fully imposed collective responsibility in the months and years leading up to the agreement. Moreover, while Davis and Johnson’s resignations adhered to the convention, the breaches did not end.

Notably, in February 2019, MPs narrowly backed an amendment to a government motion, tabled by a cross-party group, which ruled out a no-deal exit under any circumstances. The amendment passed by 312 votes to 308 – a majority of just four.

After its passage, in chaotic scenes, the government whipped its MPs to vote against the motion as amended. The amended motion ultimately passed by 321 votes to 278 – a majority of 43.

It later emerged that cabinet ministers, including work and pensions secretary Amber Rudd and justice secretary David Gauke, had abstained on this final vote. In total, four pro-Remain members of the cabinet and eight middle-ranking ministers abstained.

Greg Clark, the business secretary, defended his decision to abstain.

Clark stated: “It has been completely consistent with government policy to date that we should not leave on 29 March without a deal. And what we now have tomorrow is the ability to carry that forward. We acted completely in accordance with long-standing government policy.”

Downing Street ultimately took no action against the ministerial abstainers, which was criticised by some Brexiteers.

The Westland affair (1985/1986)

A famous instance of collective responsibility appearing to be breached concerns the Westland Affair.

In January 1986, Michael Heseltine resigned as defence secretary, sparking one of the most serious political crises of Margaret Thatcher’s premiership. Heseltine had championed a rescue package from a European consortium for the Westland helicopter company – which was suffering severe financial difficulties. In taking this stance, he clashed with Thatcher and Leon Brittan, the trade and industry secretary, who favoured a rival bid by the American Sikorsky Fiat group. Observers were hence treated to the unusual spectacle of a cabinet member (Heseltine) appearing to pursue a policy that was diametrically at odds with the government’s stated intentions.

On 6 January, the crisis deepened markedly after a “confidential” letter from the solicitor general, Patrick Mayhew, was leaked to the press. The letter accused Heseltine of “material inaccuracies” in his lobbying for a European consortium rescue package.

The immediate trigger for Heseltine’s departure, however, was a ruling by Thatcher that all public comments on the Westland controversy should be cleared through the Cabinet Office to maintain collective responsibility. Thatcher was at pains to overcome the impression that the government was at war with itself; it is also speculated that she feared Heseltine’s popularity.

In a commons statement on 23 January, Thatcher stated that Brittan – Heseltine’s main cabinet antagonist on Westland – had authorised the leaking of the 6 January letter. An inquiry, requested by Mayhew, had accused Brittan of conspiring against his cabinet colleague. Brittan subsequently resigned.

In a speech to the commons on 19 October 1986, Brittan accused Heseltine of having consistently “undermined” the government over the Westland affair.

Brittan told MPs that “after the Westland affair, I have no doubt that any future government, whatever their political complexion, will and should insist that the decisions of the government should have the support of all members, and should not be undermined from within.”

Coalition controversy (2012/2013)

On 29 January 2013, the government was defeated in the House of Commons on its policy to redraw constituency boundaries and reduce the size of the commons chamber. The defeat was orchestrated by the Liberal Democrats, the Conservative Party’s junior coalition partner, who voted with the Labour opposition against their own government’s legislation.

It marked the first time that Liberal Democrat ministers in the commons, including deputy prime minister Nick Clegg, voted against the Conservatives on a piece of coalition legislation. The move was styled as an act of retaliation after Conservative backbenchers blocked the coalition’s proposals, spearheaded by the Liberal Democrats, to reform the House of Lords the previous year.

MPs debated the principle of collective ministerial responsibility in Westminster Hall on 13 February 2013 – in light of the Liberal Democrat rebellion.

Conservative backbencher Christopher Chope argued that the situation of ministers answering in the commons “on behalf of not the government, but the Conservative party… was rather bizarre.”

He questioned why collective responsibility was set aside for the boundary review and delivered a sharp critique of the Liberal Democrats.

Chope said: “The Liberal Democrats have a history of speaking with forked tongue. They often enunciate a different policy for different groups of potential electors in different parts of the country…

“It seems as though their attitude towards speaking with forked tongue is tainting the whole government.”

Sir Nick Harvey, a former Liberal Democrat minister, defended the dynamics of the coalition.

He stated: “Collective responsibility, in the sense in which we have understood it, can exist only where there is a collective view, a collective agreement and a collective decision between the two parts of the coalition that they will proceed in a certain way.

“Where something breaks down… it is inevitable that we will not be able to apply a traditional doctrine.”

He added: “We should not fret about that or worry ourselves unduly about it.”

It fell to Chloe Smith, the parliamentary secretary for the Cabinet Office, to explain the government’s application of the collective ministerial responsibility doctrine.

She told the chamber: “Collective ministerial responsibility is about how ministers behave towards the public and parliament, rather than towards the crown.

“However, the basic point remains the same: ministers need to be able to have frank discussions and disagreements in private, while maintaining a common purpose once a decision has been taken.”

Smith cited the famous Callaghan quote, delivered to the commons in 1977, adding: “That demonstrates that the terms, duration and enforcement of the arrangement are ultimately a matter for the prime minister.”

Additional resources

• The Ministerial Code (GOV.UK): https://www.gov.uk/government/publications/ministerial-code
• The Cabinet Manual (GOV.UK): https://www.gov.uk/government/publications/cabinet-manual
• House of Commons Library Report – Collective Responsibility: https://researchbriefings.files.parliament.uk/documents/CBP-7755/CBP-7755.pdf