Image copyright Reuters

The Scottish independence debate is in full swing, but one question that has yet to be properly answered is: what happens to the 59 MPs representing Scottish seats at Westminster if September's referendum results in a "yes" vote?

In the SNP White Paper entitled Scotland's Future, the answer was clear: the 2015 general election would take place as normal, but Scotland's candidates would be competing for curtailed, 10-month terms.

"Sovereignty will be fully exercised by the people of Scotland from the point Scotland becomes independent on 24 March 2016," it explained.

"Until that point, the people of Scotland must be represented politically at the UK level. Scotland will therefore elect MPs to Westminster to represent Scotland up until the date of independence."

But just days after the 670-page document was released, the party's Westminster leader Angus Robertson mooted an alternative course of action.

"There's a very good case for putting the UK general election back by a year," he told BBC Radio 4's The Week in Westminster in November, "because of course a yes result in Scotland will lead to a very intense period of negotiation between the UK government and the Scottish government.

"Perhaps being diverted by a general election in the middle of that process is something we need to be thinking about."

Image copyright Reuters Image caption First Minister Alex Salmond says he wants Scotland to "regain its place as an equal member of the family of nations".

But the former Conservative secretary of state for Scotland, Lord Forsyth, told the House of Lords last week that this was "fantasy politics".

"I am not quite sure what it says about democracy," agreed Lib Dem minister Lord Wallace of Tankerness, "that people should be denied the chance to elect new Members of Parliament."

'Outrageous'

He had been put on the spot by Conservative Lord Flight.

"If Scotland votes for independence, it would be inappropriate for there to be Scottish MPs at Westminster thereafter," Lord Flight said.

"What precisely are the arrangements before implementation of Scottish independence, should it be voted for, in 2016?"

In response, Lord Wallace offered merely that "a process of negotiation" would ensue, on this, at least, agreeing with Mr Robertson.

But there is little appetite in Westminster for delaying the next general election to 2016.

Labour MP for Stirling Anne McGuire told BBC Radio 4's the World at One in January: "Why should Angus Robertston and the SNP say: 'Well, sorry, people, you're going to have to wait another year'?

"It is outrageous; they have put the Scottish people on pause. They shouldn't be allowed to put the rest of the UK on pause as well."

Image copyright Getty Images Image caption Mr Robertson argued that the 670-page blueprint for independence was the most detailed document of its type ever produced

Conservative MP Steve Brine said: "I hope we avoid a Labour government, but the polls suggest that is a possibility.

"Now Labour has 41 MPs in Scotland. Let's suggest that Labour come back with a majority of 30 to 40 seats. What then happens?

"Does PM Ed Miliband have to legislate away his own majority, and the Labour government is no longer viable here in Westminster? That is another big scenario question, which we don't hear an answer to."

No-confidence vote

Constitutional expert Prof Robert Hazell, also appearing on the same programme, pointed out that - in such circumstances - the UK government would not automatically fall.

"First of all, there would have to be a vote of no confidence in the existing government," he explained.

Under the the Fixed-term Parliaments Act, MPs would then have 14 days to form a new government that could command their confidence.

Only if that fails would new elections be held.

Prof Hazell speculated: "One outcome would be that Labour would continue in a minority government, because the other parties in the Parliament might decide that they didn't want to bring the government down.

"They might decide they would exert greater leverage over the government by keeping it as a minority."

Image copyright PA Image caption The future leader of a minority government?

Ultimately, as Mr Robertson noted in November, it is for the UK government in Westminster to decide on its election policies, and so it would decide how to proceed if Scotland does vote yes.

But, he argued, an independent Scotland would be "significantly better off, democratically, economically, socially".

If an independent Scotland joined the EU and the UN, he went on, it would work with "our neighbours and friends on these islands... in a new way, as equals".

This would be "eminently sensible and far better than the situation where more regularly than not we in Scotland have governments in Westminster that we don't even elect pursuing policies that are often, sadly, to our disbenefit", the SNP MP added.

"The consequences of independence are that we don't need to send elected politicians like myself to London. Hooray, what an improvement!" he said.

"Coincidentally we can save a lot of money while we're at it."