One of Scotland's most senior police officers will face charges of gross misconduct amid allegations he cheated on an elite command course.

Assistant Chief Constable Wayne Mawson was this summer accused of passing a subordinate's work off as his own as he tried to secure the qualification necessary to keep his job.

Now the Police Investigations and Review Commissioner (Pirc) Kate Frame has confirmed that an investigation has begun in to allegations which, if true, would amount to gross misconduct.

The Herald earlier this month revealed that Ms Frame's team were considering whether such allegations would, if substantiated constitute gross misconduct.

The matter had been referred to them by the main civilian watchdog for policing, the Scottish Police Authority or SPA.

The decision to go ahead with a full-scale probe means that Mr Mawson, still in control of extremely difficult policy areas, such as stop and search, will live with further uncertainty amid career-threatening allegations.

Ms Frame's office has issued a statement reflecting the complexity and gravity of the investigation.

It said: "The Commissioner has assessed that the conduct which is the subject of the allegation would, if proved, amount to gross misconduct.

"Once the investigation is complete, the Commissioner must determine whether, in the investigator's opinion, the senior officer has a case to answer in relation to the misconduct allegation.

"The Commissioner must submit a report to the SPA containing a summary of the evidence and the investigator's opinion on whether the allegation should be referred to a misconduct hearing.

"Where the Authority determines that there is a case to answer in respect of either misconduct or gross misconduct, it must refer the misconduct allegation to a misconduct hearing."

The Mawson case was passed to Ms Frame's team after the SPA's complaints and conduct committee heard the case on September 29.

This was months after it was first brought to their attention after an initial investigation by Police Scotland's own professional standards officers. The complaint was formally sent to the authority by Neil Richardson, Police Scotland's deputy chief constable. The SPA could have decided not to refer to PIRC.

Force insiders have already described how the claims, even though they have not been proved, have sent shockwaves through the highest ranks in Police Scotland.

This is because Mr Mawson is widely seen as a close ally of, and even potential long-term successor to, chief constable Sir Stephen House, pictured above, who is retiring.

It is also because Mr Mawson has also been one of the most politically high profile chief officers in Scotland.

As the public face of controversial stop-and-search tactics, he drew intense fire inside Holyrood and out.

The accusations of cheating relate to Mr Mawson's attendance at the UK College of Policing's prestigious Strategic Command Course (SCC) in Sunningdale, Berkshire, earlier this year.

Normally an assistant chief constable would be expected to have already passed the two-month Sunningdale course or an equivalent before taking up their post.

However, Mr Mawson was appointed ACC, with responsibility for community policing in western Scotland, without having completed the command course. He graduated in March, at his first attempt, two years after being appointed.

One of the tasks at the course was to design a new system for dealing with a particular branch of policing. It is alleged that Mr Mawson, pictured above, submitted work carried out by an officer under his command. That officer is not thought to be under investigation.

It is understood that all command course candidates had signed a document saying all work would be their own.

Complaints against senior officers are not uncommon. A cheating allegation is, however, unusual.