A POLICE superintendent is under investigation for not wearing shoes in his office in a case which has been highlighted amid growing concern over zealous internal probes in Scotland's national force.

The officer - who has not been named - is also understood to be facing more serious allegations.

But his staff association, the Association of Scottish Police Superintendents (ASPS), raised his case as it voiced concerns over the "proportionality" of counter-corruption and professional standards investigations.

An assistant chief constable, John Mauger of the old Central Scotland Police, was on gardening leave for years after a £2 million investigation before being cleared of a series of allegations. He was, however, found to have not been wearing his hat on duty.

Labour and SNP MSPs have already called for an inquiry into police internal investigations and the justice committee at the Scottish Parliament is scheduled to discuss complaints against the force today.

ASPS President Niven Rennie acknowledged that investigations should be "thorough and transparent". But he expressed frustration - widely shared by force insiders - that "ludicrous allegations" such as the shoeless super were the subject of lengthy probes.

He said: "There is a need for proportionality no matter where in the service one finds oneself.

"It is becoming apparent that there is a greater willingness to investigate senior officers when some of the allegations being made against them should be dismissed at the outset.

"It is also evident that some of these inquiries are taking far too long to conclude which impacts on their confidence and their health.

"This is particularly true at superintendents, in the main dedicated public servants, who can face lengthy investigations of certain allegations, some of which appear ludicrous at the outset."

He said the more "frivolous allegations can de-value the whole process".

He added: "We have a colleague at present who is facing some serious allegations - amongst these is an allegation of 'not wearing shoes in the office thus bringing the force into disrepute'.

"The need to fully investigate such a ludicrous allegation is beyond me but the impact on our members in such circumstances cannot be understated.

"We would simply ask if this is the best use of valuable public money."

MSPs asking for an inquiry into police internal investigations include Labour's Graeme Pearson, a former senior officer, and the SNP's Linda Fabiani.

Last week Ms Fabiani said she feared "a lack of transparency and potential culture of secrecy" within the police's internal investigations was "not always conducive to the fair treatment of individuals".

Mr Pearson said he wanted to see the Scottish Police Authority, the force's civilian watchdog, take a bigger interest in such matters.

Solicitor Aamer Anwar has accused the police of using data protection as a catch-all offence for officers.

He wrote to Chief Constable Stephen House with a series of complaints after two of his clients were cleared of such offences when a sheriff ruled there was no case to answer.

Sheriff William Totten, speaking at Glasgow Sheriff Court last month, questioned why constables Andrew Reid and Amanda Daly were before him at all after a five-and-a-half-year investigation.

Aamer Anwar described their prosecution as "tantamount to a witch-hunt".

Police Scotland had no comment on Mr Anwar's complaint. The force also had had nothing to say on the case of the shoeless superintendent.

Superintendent John McKenzie, of Professional Standards, said: "It is not appropriate to make comment on individual cases. We have robust procedures in place to deal with complaints."