Alex Salmond is to be investigated over his role in Perth transport mogul Brian Souter’s controversial knighthood.
He will face the embarrassing probe after a Labour MP complained that Mr Souter had been nominated for the honour days before making a £500,000 donation to the SNP.
When the award was made public in June, Mr Salmond claimed he was “just not involved in the process in any way.”
But the Cabinet Office subsequently revealed that the nomination, which is normally kept strictly confidential, had in fact come from the Scottish Government.
This is disputed by the SNP, which says a group of independent civil servants administer Scottish nominations and ministers have no role in the process.
Nevertheless, in a letter to Labour MP Jim Sheridan who demanded the investigation Mr Salmond confirmed he would refer himself to the independent advisers on the ministerial code. Lord Fraser of Carmyllie will conduct the probe.
Mr Sheridan said: “The fact that Alex Salmond has agreed to submit himself for investigation is welcome because the focus of this entire cash-for-honours controversy is ducking, diving, dodging and denying.
“Alex Salmond continues to evade the fundamental question of why his government nominated Brian Souter for a knighthood, and then misled me about it.
“Until the First Minister answers that then this issue only highlights Mr Salmond’s arrogance and lack of judgment.”
But a spokesman for Mr Salmond insisted they had “total confidence” in their position and rejected the complaint as “entirely spurious.”
“All three complaints previously considered by the independent advisers in the last parliament were dismissed and we will similarly accept the results of Lord Fraser’s findings in this case we only ask that Mr Sheridan does the same.
“Labour are guilty of hypocrisy. By their own admission, Labour ministers in the last Holyrood administration did make nominations for honours and blocked them and we are still waiting for Labour to publish the list of the nominations they made, and why.”
Sir Brian, the Stagecoach founder, said he would donate £500,000 to the SNP in February, shortly after the nomination was made. He was knighted in the birthday honours list for services to transport and to the voluntary sector.
The case is the first referral under the code since the resignations of the two previous advisers, former Scottish Parliament presiding officers David Steel and George Reid.