First Minister 'confident' Jenny Gilruth did not breach ministerial code
The Tories had accused Ms Gilruth of breaching the code by delaying rail works to benefit her constituents.
Humza Yousaf has said he is confident Jenny Gilruth did not breach the ministerial code in a decision on rail works while she was transport minister.
The Conservatives had accused her of breaching the code by delaying rail works to benefit her constituents.
The row centres on proposed line electrification work between Edinburgh Haymarket and Dalmeny in West Lothian which would have caused eight days of disruption from Boxing Day last year.
Ms Gilruth, who represents Mid Fife and Glenrothes as an MSP and is now Education Secretary, asked for the works to be postponed.
Tory leader Douglas Ross formally asked the First Minister to investigate the matter after raising it in Holyrood on 18 May.
Today he responded in a letter to Mr Ross, clearing Ms Gilruth of breaking the code.
The First Minister said: "I have considered this matter carefully and I am confident that it does not constitute a breach of the Scottish ministerial code.
"It is evident not only in Scottish Government advice on these rail works but also in ScotRail's own paperwork that whilst Ms Gilruth's constituency was affected, so were many others across Fife, central Scotland and the east coast of Scotland, with the likelihood of reduced services between Edinburgh and Dundee, Fife to Edinburgh, and up to Perth."
He continued: "There is no evidence to suggest that Ms Gilruth's constituency would have been impacted to a greater degree than any of the other constituencies.
"I am therefore satisfied that there was no impropriety and that Ms Gilruth was acting entirely legitimately in seeking advice on the network wide impact of rail works on a major piece of national infrastructure."
A Scottish Government spokesman said: "The First Minister considered the matter carefully and concluded that it does not constitute a breach of the Scottish ministerial code."