SCOTLAND’s undercover policing probe in embroiled in a conflict of interest row after it emerged that one of the team members is a former detective who managed a covert unit.

Stephen Whitelock, who is working on the review by Her Majesty’s Inspectorate of Constabulary in Scotland (HMICS), was the deputy director of the specialist police force in charge of undercover activities.

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Labour MSP Neil Findlay said: "There is a very clear and obvious conflict of interest here and the Scottish Government must act. The credibility of the HMICS review is in danger of being totally undermined."

A judge-led inquiry is investigating undercover policing in England and Wales after a wave of scandals about the controversial practice.

Officers in two historic units run by the Met - the Special Demonstration Squad, and the National Public Order Intelligence Unit - infiltrated peaceful protest groups and had sex with women they were spying on.

However, although some of the officers visited Scotland on duty, the Pitchford Inquiry has not been extended north of the border, despite cross-party support for the move at Holyrood.

Justice Secretary Michael Matheson tried to fill the gap by directing HMICS to carry out an “independent” review of undercover policing in this country. The Inspectorate is expected to focus on the period from around 2000 onwards.

The Herald can reveal that covert policing, prior to the creation of the single force, was the responsibility of the Scottish Crime and Drug Enforcement Agency (SCDEA).

The SCDEA had its own “special operations” section that assisted undercover operations throughout the country.

Mr Whitelock joined Strathclyde Police in the 1970s and worked his way up the ranks before joining the SCDEA in 2008.

He was appointed deputy director general in 2013 before retiring and becoming a lead inspector at HMCIS.

An inspectorate spokesman confirmed Mr Whitelock would be working on the HMICS probe, which will be led by Derek Penman, who is the most senior figure in the organisation:

“Support for the review will be drawn from within HMICS and will include Stephen Whitelock, who has significant experience and expertise in covert policing. Stephen retired from policing in March 2013.

“As a former Deputy Director General of the SCDEA, he had previous management responsibility for all business areas including Special Operations, although the oversight of individual undercover policing operations in Scotland would at that time have been the responsibility of each individual authorising officer from across the then 8 legacy forces and Agency.”

The spokesman added: "The Special Ops unit at the SCDEA provided advice and assistance to Scottish policing in relation to undercover policing operations."

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Mr Whitelock faced similar conflict of interest claims over his role in a HMICS review into the single force’s Counter Corruption Unit, but a police source said he produced a very “comprehensive” report.

Donal O’Driscoll, a “core participant” in the Pitchford Inquiry who was targeted by undercover officers while in Scotland, said: "The presence of Mr Whitelock in the HMICS demonstrates why it is not an appropriate or independent body to investigate this scandal. Nobody spied upon by undercovers in Scotland can have any trust it will give the answers and justice so desperately needed."