Cabinet solidarity is the mutual agreement and support of policy decisions shared by ministers of the cabinet in a parliamentary system of government. If a member of the cabinet does not support a policy decision he is obliged to resign from his position in the cabinet. The cabinet will generally replace an empty position with someone who has historically leaned towards the cabinet's ideological and policy beliefs to re-establish cabinet solidarity.
Cabinet solidarity is a tradition in parliamentary governments in which the prime minister elects the cabinet ministers. The cabinet ministers are usually selected from the same political party as the prime minister to make collective decision-making for legislation faster and more effective. Unlike a presidential system used in the United States, a parliamentary system’s executive and legislative branches are intertwined. Because there are no equal checks and balances between the executive, legislative, and judicial branches, the prime minister relies on the cabinet to always support his or her policy decisions. A breach of cabinet solidarity (when a cabinet member publicly disagrees with an executive decision) results in a resignation or termination from that cabinet position. The NSW Parliamentary Library Research Service in Australia explains that "one aspect of collective ministerial responsibility is that Ministers share responsibility for major government decisions, particularly those made by the cabinet and, even if they personally object to such decisions, Ministers must be prepared to accept and defend them or resign from the cabinet".
In non-parliamentary governments like that of the United States, cabinet solidarity is not formally practiced. This is due to the clear separation of the executive and the legislature in policy making. The United States president's cabinet members cannot simultaneously serve in Congress, and therefore cannot vote on legislation supported by the executive. The president instead has veto power over legislation passed by Congress. Cabinet unity and collective agreement between members are important to cabinet stability and party politics, but cabinet members do not have to publicly support legislation proposed or supported by the president. It is, however, in the cabinet member's best interest to support and align with the president's policies, because they serve at the pleasure of the president, who can at any time dismiss them or appoint them to another position.
Parliamentary democracies such as Australia, the United Kingdom and Canada practice and adhere to cabinet solidarity. Rhodes, Wanna and Weller offer this description of the principle of cabinet solidarity in Westminster systems of parliamentary democracy: "Cabinet solidarity and collective responsibility are twin dimensions of responsible party government that enjoy constitutionality, albeit informally. They lie at the core of ministerial governance. Cabinet solidarity is purely a political convention designed to maintain or protect the collective good as perceived by a partisan ministry. It rests on the notion that the executive ought to appear a collective entity, able to maintain cohesion and display political strength".
In Australia, cabinet solidarity is fundamental to cabinet confidentiality, but also to protect private information from becoming public and possibly threatening national security. Cabinet solidarity is not a legal requirement, but a political convention and practiced norm. There is no written law that upholds cabinet solidarity, but it is deeply ingrained in Australia's cabinets as a political norm and is therefore an important aspect of the collective strength and influence of the prime minister's administration.
The United Kingdom practices cabinet solidarity. The prime minister selects 22 cabinet ministers from the House of Commons and the House of Lords, comparable to the United States Senate and House. Once selected as cabinet ministers, each minister is given a head position of the government departments. Four days a week, cabinet ministers respond to oral question from members of the parliament. The leader of the opposition is allowed to ask six questions to the prime minister during his weekly scheduled oral sessions. The cabinet members, along with the prime minister, schedule weekly closed door sessions to discuss the collective stance of the cabinet to avoid inconsistent responses from cabinet ministers. The solidarity of the cabinet is consistently challenged by the opposition in an attempt to create contradictions between cabinet ministers. It is therefore imperative for the cabinet members to have their responses as common and similar as possible.
A parliamentary system that uses cabinet solidarity is more likely to avoid contradictions and disagreements between cabinet members of the executive branch. Cabinet ministers are likely to feel there is a practical and collective benefit from being part of a team. Cabinet solidarity also benefits party and personal loyalty to the prime minister. Solidarity within the cabinet can strengthen the prime minister's party and accelerate policy decisions and interests of that party. Cabinet solidarity allows decisions to be made quickly by the prime minister and inevitably speeds up the process of passing legislation. Presidential democracies often lack the ability to pass legislation quickly in times of emergency or instances of national security.
Critics of parliamentary democracies say that the prime minister as head of the parliament has too much power in the passing of legislation. Because cabinet solidarity forces the cabinet ministers to publicly agree with the prime minister's decisions, political debate and internal discourse is hindered. Recent reports from the United Kingdom suggest that cabinet government has "progressively weakened" since the Second World War, and virtually disappeared under Prime Minister Tony Blair. When disagreements occur within the cabinet, collective agreements can be nearly impossible, resulting in the stoppage of policy change and new legislation. Cabinet solidarity is therefore dependent on the mutual agreement and collective unity of the cabinet and its members.
- Leroy Way. "British and American Constitutional Democracy".
- Griffith, Gareth (2010). Minority governments in Australia 1989-2009 : accords, charters and agreements. [Sydney, N.S.W.]: NSW Parliamentary Library Research Service. ISBN 978-0-7313-1860-5.
- Petersen, Eric (19 May 2005). "Congress: A brief comparison of the British House of Commons and the U.S. House of Representatives". Congressional Research Service: 3–15.
- Rhodes, R.A.W.; Wanna, John; Weller, Patrick (2009). Comparing Westminster. OUP. p. 127. ISBN 978-0-19-956349-4.
- Foster, Christopher (2005). British government in crisis : or the third English revolution. Oxford: Hart. ISBN 1-84113-549-6.
- Press Association (29 May 2007). "Blair cabinet took one decision in eight months". The Guardian (London). Retrieved 17 March 2012.