JENNY Gilruth is dazzlingly innocent. Never has a human being - if she is merely mortal - been so blameless, so pure, so close to perfection as the SNP MSP for Glenrothes.

As transport minister, she was immaculate. An angel. Babes smiling in their cribs were like unto writhing vermin next to her. Abominations, they hid their faces in shame. Ick.

At least, that was the gist of Humza Yousaf’s message at FMQs as the heretic Douglas Ross suggested Ms Gilruth had been doing sly favours for Fifers.

Press reports and FoIs suggested she snubbed official advice to keep trains running through her constituency between Christmas and New Year.

Her decision to delay an eight-day shutdown for repairs cost an extra £1million and the work still hasn’t started, but hey, the line to Markinch stayed open for the Sales.

“Preferential treatment,” scowled the Tory leader, just back from the Coronation.

Mr Yousaf said it was a “very serious accusation” and would be “appropriately investigated”. 

However, come to think of it, he’d already decided she was in the clear.

She acted for the “correct reasons", he declared, on the basis of reading the Daily Mail.

Mr Ross thought that a timetable change too far. “He said he’s going to investigate, but he also said he investigated this morning and sees no fault in what Jenny Gilruth did!”

Mr Gilruth, now education secretary, started to act up in class.

As she ranted across the aisle, Presiding Officer Alison Johnstone reminded her of the rules on “behaviour in the chamber”. Ms Gilruth nodded and ranted a little quieter.

Ms Ross steamed on. She should have recused herself because of a conflict of interests, he said. It was a “clear-cut sackable offence” under the ministerial code.

Mr Yousaf, who polices the code, doubled down on his neutrality, and laid out the case for the defence.

She only wanted to help folk “rightly travelling up and down the country to see their loved ones”. So, “rightly in my view”, she made Network Rail drop the shovels.

“This is getting worse,” said Mr Ross. “He’s now saying Jenny Gilruth was right to do this.”

Was her “micromanagement” also behind the chair of ScotRail quitting around that time, he wondered snarkily.

Mr Yousaf’s neutrality boiled over. 

An “undoubtedly desperate” Mr Ross was trying “to throw as much mud as possible”, he fumed. Ms Gilruth’s approach was “absolutely right”.

Mr Ross scoffed. Instead of “looking at it over breakfast”, how about a proper investigation?

Mr Yousaf rolled his eyes. How many times did he have to exonerate this paragon of virtue? 

“We take the ministerial code extremely seriously," he said.

And besides, it was her trainset.