Scotland’s right to decide its constitutional future should become a central question in the forthcoming Scottish Labour leadership contest, according to SNP MSP David Linden.

His intervention follows media reports suggesting Scottish Secretary Douglas Alexander intends to remain neutral during the contest to choose the party’s next leader.

Linden argues that while Alexander may choose not to support a particular leadership candidate, neither he nor those seeking the leadership can remain neutral on whether people in Scotland should have the right to decide their constitutional future.

The SNP has repeatedly challenged Labour’s opposition to another independence referendum and is now seeking to place the issue before candidates competing for the Scottish leadership.

The intervention follows Labour’s defeat in May’s Scottish election under former leader Anas Sarwar, with the SNP arguing that the party’s constitutional position contributed to its result.

Linden also criticised comments made by Alexander during the election campaign, when he said around 30% of Scots viewed politics “through the lense of identity” and were therefore “immune to arguments”.

David Linden said:

“Douglas Alexander is staying neutral on the Scottish Labour leadership contest, but neither he, nor the leadership contestants, can stay neutral when it comes to Scotland’s right to decide.

“Scotland is a nation, and therefore must have the right to decide our own future, I do not expect pro-union voices in Labour to back independence, but surely we must all agree that it must be the choice of the people in Scotland, not ministers in London.

“There has been some rumblings on this from Labour voices, and if I was in Labour I’d be asking any future leadership how they plan to answer the question of self-determination for Scotland, otherwise they will just continue to lose elections in Scotland.

“The only party that will always keep Scotland moving towards independence is the SNP.”

The argument Linden is making draws a distinction between supporting independence and supporting the principle that Scotland should be able to choose whether it becomes independent.

That distinction is now being placed directly before whoever seeks to lead Scottish Labour next, with the party’s position on another referendum likely to remain part of the wider debate over its political direction following May’s election result.

For the SNP, the question is straightforward: Labour does not need to support independence to accept Scotland’s right to decide, but Linden argues that continuing to oppose that principle risks leaving the party facing the same constitutional argument at future Scottish elections.