#Indyref2 on the back of a big SNP win is not going to happen – here's why

Scottish Labour leader Jim Murphy has warned that if the Scottish National Party (SNP) wins the vast majority of Scottish seats in this election, Scotland will be “turbo-charged towards a second referendum”. The poll evidence suggests that one part of this statement is true: the SNP is on course to win the vast majority of Scottish seats.

No manifesto, no appetite

But the evidence that there will be another referendum so quickly is thin on the ground. This makes Murphy’s warning seem like a last desperate attempt to convince No voters that their new support for the SNP will have dire consequences. Here is why a quickfire second referendum will almost certainly not happen.

First, the SNP leadership has not asked for it. Its manifesto includes no reference whatsoever to a second referendum. Instead, it promises to use its position of strength to make the most of the first referendum: to hold the UK government to the promise, made by the three main UK parties, to devolve extensive new powers for Scotland.

Second, the SNP leadership does not want a referendum right now. It will take a lot more than an excellent showing in one election to convince it to try again. Instead, it will seek evidence that there has been a so-called “material change” in circumstances. In the short term, the only change would be caused by events: the Conservatives forming the next government, holding an EU referendum, and the UK voting to leave the EU while Scotland votes to stay in, prompting a constitutional crisis.

Sturge is in churge.Danny Lawson/PA

Even then, a new referendum is not inevitable. In the longer term, a material change of the sort that would justify one involves either remarkably high opinion-poll support (say, over 60%), or clear majority support for a long time (say, over a year) or some combination of the two. No one in the more sensible side of the SNP would want to hold a new referendum on a whim.

The people who want to use the result to declare independence without a vote, or hold a new referendum immediately, do not control the party. Nicola Sturgeon may not have ruled out putting a referendum commitment in the manifesto for next year’s Scottish election, but the indications are that it is very unlikely. Even if the party won every seat in Scotland on May 7, it would not be enough on its own to change the policy.

Third, it takes more than moral authority or a political shock to hold a referendum. Remember what it took to secure the first referendum: the SNP made it a key plank of its 2011 Scottish election manifesto; it won a majority of seats in the Scottish parliament; and it negotiated the wording and timing of the referendum with the UK government. All three steps were necessary to ensure that a vote took place. It would be ridiculous to suggest that a UK government would follow up this vote with a second referendum on a whim, particularly since there has been no request from the SNP and we have witnessed general refusal by the other parties during the election debates.

More importantly, I would argue strongly that a second referendum is not the story of this election. The story is that the SNP is about to remove the last leg of Labour dominance in Scotland. It is difficult to overstate just how much Scottish Labour used to dominate all forms of elections in Scotland, and how much the SNP has replaced it as Scotland’s main party. Let’s not skim over this remarkable fact to focus on idle speculation.