Lord Hardie told MSPs that he had feared disclosure of the sum would result in journalists “pestering” him at home, although he conceded this had not happened and said he now accepted the information “should be in the public domain”.

It emerged in 2023 that Lord Hardie had been paid £1,056,181.59 between 2014 and August 2021 to chair the inquiry. The figure was only made public after the Daily Record appealed to the Scottish Information Commissioner.

A spokeswoman for the inquiry said at the time that he was “being paid on the basis of a daily rate for the hours that he works on inquiry matters”, adding: “The daily rate is the standard fixed by the Scottish government for retired judges.”

The Scottish Parliament’s Finance and Public Administration Committee is examining the cost-effectiveness of public inquiries in Scotland, amid fears they are consuming “significant sums of money”. The tram inquiry cost more than £13m and took nine years to produce its final report.

During a committee hearing, Conservative MSP Craig Hoy noted that Transport Scotland had been “very resistant” to the publication of Lord Hardie’s salary and asked whether he had been consulted about the disclosure.

Lord Hardie replied: “Yes, I was consulted about it, and I did indicate that I thought it was unreasonable. But I’ve accepted the position that it’s in the public domain and it should be in the public domain.”

Pressed further, he said: “I thought, at one point, it was unreasonable that it was released because I anticipated that it would result – wrongly anticipated that it would result – in the media attending my house and pestering us.”

Asked whether this concern was a sufficient reason to withhold the information, he responded: “Well, without going into my personal circumstances, yes, because of health and other issues.”

The tram inquiry was set up in June 2014 to examine delays, cost overruns and reduced scope in Edinburgh’s tram project. The final report was not published until 2023, a timeline that drew regular criticism.

Lord Hardie told MSPs he was “always concerned about views expressed about the time it was taking, but there was really nothing else that could be done, given the challenges that we faced”.

Asked whether he would have taken the role had he known it would last nine years, he said: “I think I would have preferred to have spent my time with my grandchildren.”

He added: “Certainly, if anybody asked me now even to do a one-year inquiry, I think I would just go back to the grandchildren.”