Having been regarded as almost certain winners for most of the past two years, Britain’s Conservatives are understandably unhappy at the prospect of missing out. With the polls still showing a hung parliament as (narrowly) the most likely outcome, attention has turned to how the party leaders would respond.

On Monday The Independent reported that “David Cameron is set to claim victory if Labour comes third in Thursday’s election even if he fails to win an overall majority”; yesterday’s Guardian accused Cameron of being “prepared to ignore the rules … designed to allow for a week of discussions between the party leaders on forming a coalition”.

This produced some synthetic outrage from the Labour side, with claims the Tories were defying constitutional precedent and threatening to drag the Queen into party politics. (And also some sensible commentary: see for example The Guardian‘s Ruth Fox.)

This is relatively new territory in Britain, which has not had a hung parliament since 1974. But it seems more like déjà vu in Australia, because it raises the same issues that were extensively canvassed in Tasmania after the March 20 election, when Labor won fewer votes than the Liberals but the same number of seats, and ultimately formed a new government with the support of the Greens.

The constitutional position can be quickly summarised. A prime minister remains in office until something happens to force them out: death, resignation or dismissal. A prime minister who loses an election — that is, the opposition party or coalition wins a clear majority — will always resign. If the election result is in any way unclear, the prime minister is entitled to remain in office and test the new House of Commons; if they then lose a vote of confidence, they must resign (a prime minister who refused to do so would be dismissed).

If the Tories win the largest number of votes and/or seats, but fall short of a majority, Cameron is perfectly entitled to declare himself the winner (as Scottish Nationalist Alex Salmond did in a similar situation in Scotland in in 2007). But that has zero effect on the constitutional process. The incumbent is fully entitled to exhaust the possibilities of negotiation for a coalition or support for a minority government.

Gordon Brown, of course, has not made David Bartlett’s mistake of promising to let his opponent have first go at forming government. But even if Brown gives up the attempt and advises the Queen to send for Cameron, Cameron still has to answer the same question that Will Hodgman stumbled on in Tasmania: can you command a parliamentary majority?

This is where the Queen has an element of discretion. If Cameron says something along the lines of “I’m not sure, but I’m willing to give it a try”, she may let him. Or she may go back to Brown and ask him to meet parliament as prime minister and see what happens (although of course she can’t force him to if he refuses). We can be reasonably confident that, with nearly 60 years experience in the job, the Queen will give this careful consideration and not be swayed by any cheap publicity stunts.

In 1974, outgoing prime minister Ted Heath stayed in office for four days after the election, trying to work out a deal with the Liberal Party. When that failed, he resigned, and Labour’s Harold Wilson took office despite lacking a majority. Once in office he knew that if he were defeated in parliament he would have the option of holding a fresh election — which duly happened seven months later.

Without a written constitution, these sort of procedures in Britain always have some vague edges, but that’s not necessarily a bad thing.

Generally, the conventions are robust enough to deal with any likely situation. Politicians will jockey for advantage and throw in some red herrings, but they will not change the underlying reality: if some combination of parties are willing to co-operate and have a majority between them, they will ultimately get to form a government.