UNDER what the British state laughably calls the “constitution”, the members of one political party will shortly get to decide who is the new prime minister of the UK.

The Conservative and Unionist Party will choose their new leader over the next couple of months and because the Tories are in government – in office but not in power, some would say – with the support of the Democratic Unionist Party of Northern Ireland, that person will become prime minister.

So the party which was voted for by less than 30% of the 46.8 million electorate in the 2017 General Election - they gained 42.3% of the votes on a 68.8% turnout – will dictate who will reside in No 10, theoretically until June 2022.

WHY WAS NO ONE READY TO STEP INTO THE JOB?
THE farce of having a “lame duck” prime minister who will still be in office throughout the whole Tory leadership election is happening because the unwritten British “constitution” doesn’t do vice-PMs. There have been plenty of deputy prime ministers, dating back to Clement Attlee in Winston Churchill’s wartime Cabinet, but Theresa May opted to do without one, and in any case the “constitution” would not allow such a person to automatically assume office as PM. It did happen, funnily enough, when Churchill retired in 1955 and his deputy and foreign secretary, Sir Anthony Eden, moved seamlessly into No 10 because no other Tory MP was prepared to stand against him.

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Eden, it should be noted, immediately called a General Election as he realised that he needed the backing of the country. He was rewarded with the highest percentage vote for any party in the post-war era at 49.7% and an overall majority of 58 seats. In Scotland the Conservatives won more than half the public vote, a performance since matched only by the SNP in 2015.

Since the First World War, no fewer than 12 prime ministers have gained the office other than by winning a General Election, including Churchill in 1940, James Callaghan in 1976, Gordon Brown in 2007 and May herself in 2016. Of that quartet, only May remained prime minister after a subsequent General Election.

HOW WILL IT BE DONE?
THERESA May’s resignation will be submitted on Friday, June 7, after the state visit of US president Donald Trump.

Sir Graham Brady was chair of the 1922 Committee of all Conservative MPs and would have helped conduct the election and act as returning officer, but has stood down as he is considering running for the leadership. It is now the case that Brandon Lewis MP, the chairman of the party, will run the election alongside MPs Dame Cheryl Gillan and Charles Walker, who were vice-chairs of the 1922 Committee but have now become joint chairs.

Each MP wanting to stand must have the support of at least two MPs and must register their candidacy in the week commencing Monday, June 10.

Eight MPs have already stated in public that they will do so – in alphabetical order: Michael Gove, Matt Hancock, Jeremy Hunt, Boris Johnson, Andrea Leadsom, Esther McVey, Dominic Raab and Rory Stewart. In addition, Steve Baker, Sajid Javid, Penny Mordaunt, Priti Patel and Brady have all been tipped as runners but are yet to state their intentions either way.

The National: Rory Stewart looks likely to be the candidate backed by the Scottish ToriesRory Stewart looks likely to be the candidate backed by the Scottish Tories

It is likely that some of the eight declared candidates and the others yet to declare will stand down once they realise that they have ideas above their station and really should be supporting the likely winners in order to get a Cabinet seat.

If there are three candidates or more by June 14, the following week will see the “exhaustive ballot” process begin in which the candidate with the least votes drops out after repeated secret voting among Tory MPs. Other candidates will see the way the wind is blowing and also drop out, leaving two, or maybe even just one, final candidate.

That should all be done by June 29 or earlier. If there are two still standing and neither refuses to concede, the issue will be put to the Conservative Party membership as a whole – 124,000 were registered as of March.

Hustings will be held around the country, there will most likely be a televised debate and the votes will be counted some time in July.

WHAT COULD GO WRONG?
THE Tory leadership election process is tried and tested but is not always the smooth process it should be. Leadsom’s withdrawal from the leadership election after David Cameron resigned in 2016 left the field clear for Theresa May and negated the whole idea of an elective mandate for the new leader.

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Most party members do not want a repeat of that single candidacy outcome as they want to hear a genuine debate that gives the two final candidates the chance to put over their views.

One question will dominate the leadership contest: what will candidates do about Brexit, and are they wanting no deal or a changed deal? The Tory Party’s faultlines will thus be laid damagingly bare – but then their divisions over Europe have been there for generations...

WHAT WILL HAPPEN AFTER THE NEW PM IS CHOSEN?
WHAT should happen is the new prime minister having the courage to go to the country as Anthony Eden did in 1955. But with the Brexit deadline drawing ever closer and the Tories due for a hammering regardless of who is in post, the new prime minister will most likely attempt to reach a compromise within the party to muddle through to 2022 with the help of the DUP.

Scotland won’t get a mention.