Q&A: Scottish independence referendum

The Scottish National Party is to be returned to government in Scotland, after winning an outright majority in the Holyrood election.

That means the SNP will hold a referendum on independence within the next few years - but what are the main issues and obstacles facing the party?

The campaign for Scottish home rule began in earnest almost as soon as the unification with England took place, in 1707.

At the time, the view was that Scotland was in desperate need of financial support, but opponents of the move were outraged by claims that the Scots who put their names to the Act of Union were bribed.

The best known critic at the time was Scotland's Bard, Robert Burns, who was spurred to write: "We are bought and sold for English gold. Such a parcel of rogues in a nation."

Fast forward many years to 1934, and the establishment of the Scottish National Party, created through the amalgamation of the Scottish Party and the National Party of Scotland.

After decades of ups-and downs, the party won its first election in 2007 and, again, in 2011.

Scottish devolution in 1999 presented a significant opportunity for the SNP, which, despite having a few MPs, was struggling to make the case for independence at Westminster.

The prime minister of the day, Tony Blair - who wrote the book on incumbency - was all too aware of this, and the Scottish Parliament's part first-past-the-post, part PR voting system was intended to prevent any one party gaining an overall majority.

This was the case initially - up until the 2011 election there had been two terms of a Labour/Lib Dem coalition and one of an SNP minority government.

The 2011 result has blown out of the water the claim once made by Labour veteran Lord Robertson that devolution would "kill nationalism stone dead" - ironically, Labour, the party which set up devolution - has never managed to gain the overall majority achieved by the SNP.

That result means the independence debate is now more relevant than it has ever been - a referendum will be held.

Hard to say at the moment - while it's probably true to say support has grown, given the election result, a vote for the SNP does not necessarily mean a vote for independence.

One of the reasons voters turned so decisively to the SNP and its positive campaigning style was because they wanted an alternative to Labour and to punish the Liberal Democrats at the polls.

There are those who do not support independence, but recognised Alex Salmond was the best candidate for first minister - knowing they have the safety-cushion of voting "No" in the referendum.

In terms of political backing at Holyrood, the SNP supports independence, as do the Greens and independent MSP Margo MacDonald, a former nationalist politician.

Labour, the Tories and the Liberal Democrats are opposed.

At the moment, SNP leader Alex Salmond is only prepared to say the referendum would be held at some point in the second half of the new parliament's five-year term.

He says the most pressing issue is gaining more significant powers for the Scottish Parliament - especially financial powers - because that debate is currently going on at Westminster.

Opponents say that is an excuse for the SNP wanting to dictate the conditions for a "Yes" vote, while claiming the party played down the issue during the election campaign.

They want the referendum to be held now.

Even though the party won an overall majority, it takes the view that, on an issue of such significance, it would first need the backing of the Scottish people in a referendum.

It also needs this mandate to negotiate an independence settlement with the UK government.

Firstly, MSPs would pass a Referendum Bill in the Scottish Parliament.

There would then be a for-and-against campaign, like the one we saw for the AV referendum, before Scots voters went to the polls.

It's nowhere near as simple as that.

Because the Scottish Parliament does, in itself, not have the authority to declare Scotland an independent country, a "Yes" vote in the referendum would mark the start of talks with the UK government.

Of course, if the Scottish people speak up for independence, it makes it all but impossible for Westminster ministers to say: "No, you can't have it."

The SNP has previously indicated the question on the ballot paper would go something like: "The Scottish Parliament should negotiate a new settlement with the British government, based on the proposals set out in the white paper, so that Scotland becomes a sovereign and independent state."

The responses would be "Yes I agree" or "No I disagree".

In the last parliament, the SNP minority government tried to get enough support for a referendum with Lib Dem votes, offering the olive branch of a second question on the ballot paper on increased powers for the Scottish Parliament.

Ultimately, they didn't go for it. The SNP doesn't have to barter for votes any more, but Alex Salmond doesn't rule out a second question this time round, saying his party has no "monopoly on wisdom".

Talks would begin with the UK government on a constitutional settlement, based on the SNP's declaration of a popular mandate from the Scottish people.

It's hard to say exactly how things would happen, given this would be new territory, but it's likely the timescale from a "Yes" vote to full independence would be lengthy, given the huge number of issues which would need resolved, including areas like defence.

Alex Salmond has described the independence referendum as a once-in-a-generation event.

All the parties - unionist and pro-independence - are keen to avoid the situation which has unfolded in the Canadian province of Quebec, where debate over multiple independence referenda over the years has been dubbed the "neverendum".

At worst, a "No" result in the referendum could spell the end for the SNP as a mainstream political force.

It's also likely focus would shift back to the debate over more powers for Holyrood - with full fiscal autonomy, as opposed to relying on the Treasury block grant, probably becoming a more serious option.

As far as the referendum is concerned, none.

The SNP now has the votes at Holyrood to stage it, unlike in the last parliament when the SNP minority government was out-numbered by the votes of the pro-union parties, namely Labour, the Tories and the Lib Dems.

The UK government says it won't stand in the way of an independence referendum.

That's all very well, but the bottom line is this is happening - whether the coalition likes it or not.

In terms of independence, the UK government would essentially have to agree to it, but in the event of a "Yes" vote it would be almost unthinkable for Westminster to block it.

Westminster is currently considering the Scotland Bill, which will deliver new financial powers worth £12bn, allowing Scotland to control a third of its budget under a new Scottish-set income tax and borrowing regime.

It came about as a result of the Calman Commission to review devolution 10 years on, backed by a vote of the pro-union parties at Holyrood.

The SNP was not keen to engage with the Scotland Bill debate, saying a "pocket money parliament" under Westminster control was not the way forward.

But the new SNP majority government is now concentrating on strengthening what is a live bill, before turning to the referendum, under a new piece of legislation.