Analysis: Nicola Sturgeon's speech on Tuesday will define her legacy

Nicola Sturgeon is between a rock and a hard place when it comes to an independence referendum and nothing but a fully legal and enforceable vote is worthwhile putting in front of MSPs on Tuesday.

When the First Minister outlines her own ‘routemap’ for a second independence referendum in Holyrood, we assume we will finally see her political masterplan for overcoming the political stagnation which proves such a drag on Scottish politics.

It is not a question of mandates, anyone who suggests there isn’t should either push for the end of parliamentary democracy or rightly be considered anti-democratic.

The tougher question is how the SNP leader overcomes the intransigence and obvious strategic advantage at Westminster.

Ms Sturgeon could simply indicate she will request a Section 30 order from Boris Johnson, but that hits an immediate and obvious roadblock.

Some reports have suggested she will instead introduce legislation to Holyrood which sets out what would in effect be a consultative referendum, within the powers of Holyrood, perhaps with a watered down question.

But what good is such a vote when opposition parties will simply boycott it, leaving any result irrelevant and any Yes victory without genuine potency.

The Brexit referendum, technically only advisory, is a case study in why opposition consent is a necessary condition of any serious political change through referendum.

First Minister and leader of the Scottish National Party Nicola Sturgeon, will announce a routemap to a second independence referendum.

We are already seeing attacks on such a ‘pretendy-referendum’ from the Conservatives which would only intensify ahead of a vote.

Ms Sturgeon has repeatedly said any referendum she holds will be legal, and while a consultative referendum may meet that condition, legislation to that effect would be an admission of political defeat.

The last remaining option is passing legislation with some clever legal argument stating Scotland has a right to not only hold a referendum but that that vote has the same political result as a Yes vote in 2014 might have done.

That raises the prospect of court action, a probable defeat, and a new slogan in time for a 2024 general election.

Or, in a not impossible scenario, Westminster is forced to engage with a referendum the courts, rather than Number 10, has approved.

The only known is the unknown, but only one can be considered success for the SNP leader.

Make no mistake, Ms Sturgeon’s speech on Tuesday will define her.

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