Happy 300th birthday, office of the Prime Minister – or is it?

3rd April 2021

Happy birthday, office of the prime minister.

Well, almost.

The office of the prime minister was not invented in one sudden moment.

The term ‘prime minister’ came to be used generally over time to describe the main minster of the crown, and who was answerable to parliament.

For a long time, the office of prime minister was invisible to our constitutional law.

The first time it was used in a formal instrument was, we are told, when Benjamin Disraeli signed the treaty of Berlin in 1878.

Even in the twentieth century it hardly left a trace on the statute book.

And this gives us an insight in to the strengths and weaknesses of the position.

In constitutional theory, the power of a prime minister derives – ahem, primarily – from two sources.

First, the prime minister has powers derived from the royal prerogative – the fiction being that the prime minister exercises those powers on behalf of the crown.

Second, the prime minister has powers derived from commanding a majority in the house of commons – and thereby control over finance legislation.

The prime minister’s power rests thereby on two constitutional stools.

What the prime minister does not have – at least not formally – is his or her own explicit constitutional centre of gravity.

Almost everything a prime minister can and cannot do ultimately comes from, in theory, either the crown or parliament.

This, in turn, means that the office is difficult to ‘reform’ – for as there are almost no legal instruments that set out the powers of the prime minister, there is no text to amend or replace.

It would be like trying to net a constitutional ghost.

It also means that the office can be as powerful and as weak as personalties and circumstances allow – you would not be able to tell just from constitutional law alone why certain prime ministers are strong or otherwise, and how certain prime ministers lose power.

For explanations for why, for example, Margaret Thatcher and Tony Blair both left office despite winning three general elections each you will have to look at books about politics and not about constitutional law.

And so what we are celebrating is not so much three hundred years of an office but a lack of a defined office, but one at the centre of practical political power.


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6 thoughts on “Happy 300th birthday, office of the Prime Minister – or is it?”

  1. I gather that Neil Kinnock, when he was doing some research into the job for which he was applying, discovered that one of the first definite references to the office of Prime Minister was in the Chequers Estate Act of 1917 donating Chequers not to David Lloyd George, the then Prime Minister, but to the serving Prime Minister for use as a country retreat.

  2. The head of the Council to the King /Queen was and still officially is the First Lord of the Treasury. Charles James Fox coined the term ‘Prime Minister’ intending it to be derogatory, suggesting someone was too big for their boots. He forgot, despite being a journalist as well, that the Press loves a pithy phrase which contains lots of information for the readers. Almost overnight, Prime Minister became the accepted term for the head of the elected government.

  3. We’re all familiar with the idea that the Prime Minister selects all of his / her ministers. Which obviously gives the PM huge powers of patronage and of indirect control over the policies and general competence of the government.

    Presumably this right to select ministers is bestowed on the PM through the royal prerogative? Has any Queen / King since Victoria even tried to influence the PM’s choice of ministers? Has anyone else? And with what result?

  4. If you look at the nameplate on the door of No 10, it’s the First Lord of the Treasury. And try to find references to the term “Prime Minister” in statutes – its rarely used. This is an office that is primarily (pun intended) political and not constitutional.

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