STEPHEN House’s role in the hiring of a controversial police chief is under fresh scrutiny after it emerged that House has a long-standing professional relationship with the individual.

Assistant chief constable Wayne Mawson, who is under investigation over allegations of cheating on an elite course, was one of House’s “staff officers” in London.

Graeme Pearson, Scottish Labour’s justice spokesman, said the revelation raised further questions about the way the Police Scotland’s top officers were chosen.

The Scottish Police Authority (SPA) – the single force’s scrutiny body – appointed six ACCs in 2013 to lead Police Scotland.

House was on the interview panel and Mawson landed the role of ACC for Local Policing West and later took responsibility for stop and search policy. However, he was given the job even though he did not possess a key qualification. ACCs were required to have passed a “relevant” Strategic Command Course, which for UK officers has meant completion of the SCC at Sunningdale. Mawson was allowed to take up the post but sit the SCC at a later date, which he passed this year.

An anonymous complainant then alleged that Mawson had completed the SCC after presenting a junior colleague’s work as his own. The allegation was made through the Counter Corruption Unit and referred to the SPA by deputy chief constable Neil Richardson.

However, it has now emerged that Mawson worked in House’s office for around 12 months in 2004 when the latter was a police chief at the Met.

Staff officers work exclusively for their boss and are expected to set up meetings and help run the office.

One police insider described the general role: “He makes the tea, does the photocopying, manages the diary, prepares all relevant briefings and make sure all logistics are in place.”

Another source said a staff officer is a “fixer” for his chief.

House became chief constable at Strathclyde Police in 2007 and Mawson was transferred to the same force in 2009 on promotion to Chief Superintendent.

He became Divisional Commander for Glasgow North East and East Dunbartonshire Division.

Mawson’s hire is the subject of a complaint to the SPA by former Tayside ACC Angela Wilson.

Pearson said: “We have a condition in Scotland that chief officers must have completed a relevant Strategic Command Course. It is a condition because it is proof of competence.

“I am confused as to why in this case the SPA waived this condition. I would have expected – as a basic fairness to the other candidates – that the SPA would have explained this decision as others may have been disadvantaged.”

Wilson said: “It would have been appropriate for Stephen House to have said that he had been his staff officer at the Met.”

Asked if House declared the staff officer link during the interview process, a Police Scotland spokesman said: “Recruitment of senior officers is a matter for the SPA.”

An SPA spokesperson said: “ACC Mawson was one of six ACC’s appointed on merit by the Scottish Police Authority in December 2012 following an open and competitive recruitment process.”