Despite accusations of Conservative complacency in this election campaign, the party has put a great deal of effort into planning what happens if parliament is hung and they are some way short of an overall majority.
Here is what has emerged as the Tory plan:
Declare victory anyway.
Have the party's media allies strain every sinew to make that a self-fulfilling prophecy.
Insist on being given the keys to No 10 without having to talk substantively to any other party first – to avoid a coalition or any substantive policy concessions.
Make a partisan challenge to the civil service in seeking to overturn any existing constitutional convention or practice that might conceivably get in the way, or even slow this down a little.
Threaten to drag the monarchy into political controversy for partisan advantage by challenging the conventions designed precisely to avoid this.
Hold out against electoral reform, whatever the election result.
Threaten apocalyptic political and financial meltdown if anybody disagrees.
The strategy does not aim simply to speed up the Tory path to power if the party is well ahead – with, say 310 seats – where a Tory minority government is overwhelmingly the most likely outcome, and would probably take office very quickly. Its key objective is to use the vociferous campaigning of the press – no doubt amplifying interventions from friends in the City – to argue that any negotiations between parties would be democratically illegitimate, without first putting the Conservatives into power, even (or especially) if Labour and the Liberal Democrats could between them muster a majority of both votes and Commons seats.
"There is convention and there is practice and they are not always quite the same thing," Cameron said in yesterday's Independent. And today's extraordinary Guardian report – based on anonymous briefings from "senior shadow cabinet members" – reveals that the Conservatives intend to mount a partisan attack on existing constitutional conventions, and the cabinet secretary's protocols for handling a hung parliament, even though a primary motivation for these has been to protect the monarchy from being dragged into party political controversy.
It is surely quite unprecedented for a man who wants to be prime minister on Friday to have his senior frontbench colleagues launch a major – and anonymous – briefing effort to challenge the impartial cabinet secretary and the constitutional conventions 72 hours before the election. The Cabinet Office guidelines were published in February, when the cabinet secretary gave evidence about them to a cross-party Commons select committee. If the leader of the opposition wanted to challenge the referee over the rules, he had ample opportunity to do so well before the election campaign began.
Second, shadow cabinet sources surely wreck their own case when they complain of a fear that so-called "new rules" would allow the prime minister to follow Ted Heath's precedent in the last hung parliament 35 years ago. Heath, who won the most votes but secured four fewer seats than Labour, resigned four days after the election after talks broke down. He informed the Queen that instead of resigning straight away he intended to try to strike a deal with the Liberals. He would stay on in No 10 over the weekend. The palace was content with this.
Labour's shadow cabinet were in effect in purdah. The previous afternoon, in James Callaghan's words, they "decided we would not challenge Mr Heath; we would allow him to carry on and try to make any arrangement that he could. We did this because we were fairly satisfied he wouldn't be able to make such an arrangement ... The country had expressed its lack of confidence in the Conservative government ... I won't say it was improper of Mr Heath because there are no conventions on this matter. I think it was stretching the thing a bit for him ... I remember I took the bold step of saying we should allow Ted Heath to 'swing slowly in the wind'."
Third, one of the major aims of the conventions has been to keep the monarchy out of party politics. This has traditionally been understood and accepted as a particular responsibility of parties which support a constitutional monarchy. It has certainly been a keen focus of Buckingham Palace, which has always feared that being seen to exercise political discretion could significantly damage the monarchy's standing as "above politics".
Yet the Conservatives say they might sacrifice that.
Fourth, the hung parliament rules already in effect favour an opposition. Peter Kellner explained why in last week's New Statesman. O'Donnell's rules make quite clear that the election purdah remains in place, so preventing a sitting PM making major decisions to affect the course of negotiations.
The party is trying to ensure that Cameron receive the keys to No 10 before having to talk to the other parties in a hung parliament. (The strategy would be to dare other parties to vote him out and trigger another general election). So it turns out that the Conservatives – the party traditionally least in favour of a written British constitution – now challenge the well-established conventions of an uncodified constitution as inoperable if they may not seem to be in their own immediate, partisan interests. An unwritten, uncodified constitution can thus be bent to the interests of the powerful. It is a powerful example of the case for codification.
This emerging Tory constitutional doctrine is contradictory, deeply flawed, ahistorical and enormously self-serving.
Still, that doesn't mean it won't work.
This is an edited version of an article that appeared on Next Left