Deputy Prime Minister of the United Kingdom as to the absence of a formal post of Deputy Prime Minister in Britain's uncodified constitution. Theoretically the sovereign possesses the unrestricted right to choose someone to form a government following the death, resignation or dismissal of a Prime Minister. One argument made to justify the non-existence of a permanent deputy premiership is that such an office-holder would be seen as possessing a presumption of succession to the premiership, thereby effectively limiting the sovereign's right to choose a prime minister. However, only two Deputy Prime Ministers have gone on to become Prime Minister. Clement Attlee won the 1945 general election
Council of Civil Service Unions v Minister for the Civil Service Council of Civil Service Unions v Minister for the Civil Service Council of Civil Service Unions v Minister for the Civil Service [1984] UKHL 9, or the "GCHQ case", is a UK constitutional law and UK labour law case that held the Royal Prerogative was subject to judicial review. In 1984, the government of Margaret Thatcher banned employees of the Government Communications Headquarters (GCHQ) from joining any trade union for "national security" reasons by an Order in Council using the Royal Prerogative. The Council of Civil Service Unions claimed in judicial review that defeated their legitimate expectations, to collectively bargain