Because of the fusion of powers of the executive and legislative branches the prime minister relies on the cabinet to always support policy decisions.
[4] The New South Wales 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".
The United States president's cabinet members cannot simultaneously serve in Congress, and therefore cannot vote on legislation supported by the executive.
Parliamentary democracies such as Australia, the United Kingdom and Canada practice and adhere to cabinet collective responsibility.
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.
Cabinet solidarity is purely a political convention designed to maintain or protect the collective good as perceived by a partisan ministry.
Article 28.4.2° of the Constitution of Ireland states:[9] In 1992, the Beef Tribunal was investigating allegations of political corruption, and wanted to take evidence from a minister about cabinet meetings at which controversial proposals had been discussed.
[10] The Seventeenth Amendment of the Constitution was passed by referendum in 1997 to add Article 28.4.3°, which allows such disclosures in exceptional circumstances.
In 2003, Tony Blair allowed Clare Short to stay in the cabinet, despite her public opposition to the 2003 Iraq War; however, she later resigned.
Prime Minister David Cameron suspended the cabinet collective responsibility doctrine for the 2016 EU referendum, following the precedent set by Harold Wilson in 1975.
Prominent cabinet ministers including Michael Gove and Chris Grayling opted to make use of the relaxation by campaigning to leave.
[citation needed] Cabinet collective responsibility to the people also benefits party and personal loyalty to the prime minister.
Presidential democracies often lack the ability to pass legislation quickly in times of emergency or instances of national security.