POLICE Scotland has lost a legal challenge against a freedom of information ruling which it was claimed would have "a chilling effect" on the recruitment of informants in the fight against organised crime.

The single force had refused to tell the Sunday Herald last year how many Covert Human Intelligence Sources (CHIS) it had had since its formation in 2013.

However, after a ruling by former Scottish Information Commissioner Rosemary Agnew, which found that the force had wrongly withheld the figure, Police Scotland appealed to the Court of Session on Friday to have the decision quashed.

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During the appeal extracts from a briefing paper were produced which warned of an increase in efforts by organised crime gangs to identify CHIS if the information was published.

The force also raised concerns over trust and confidence with current CHIS or potential recruits being eroded.

Counsel for the chief constable, Jonathan Barne, told the court: "Police Scotland put forward materiel they thought was sufficient. They raised these issues. The commissioner says 'That's all too vague'. In my submission, in the context of this case and the potential repercussions, the commissioner was acting unreasonably."

Barne said there was concern that the disclosure together with potential other disclosures could result in the piecing together of information.

"It is information which, so far as the appellant is aware, had not been disclosed on a regional basis or a force basis anywhere in the UK," he said.

The Herald: Rosemary Agnew, the Scottish Information Commissioner

Picture: Agnew

He told the Lord Justice Clerk, Lady Dorrian, sitting with Lord Menzies and Lord Pentland, that there was concern that the disclosure could in effect require similar disclosures in future.

David Johnston QC, for the Commissioner, argued that the appeal should be refused. He pointed out that the request was for a single number for the whole of Scotland over a period of three years, and which was not broken down further.

Johnston said the decision taken by the commissioner had met the established test and that reasons given for it were intelligible and addressed the fundamental points.

The Commissioner said in her initial ruling that she was not satisfied that any of the submissions made by Police Scotland had explained how the effective use of any "relevant source" or CHIS could be compromised by disclosure of the information sought.

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On the detection of crime exemption, she said she considered "the submissions she has received are general in nature, speculative and do not evidence how disclosure of the information requested would be the catalyst of any of the harm claimed by Police Scotland.

"The Commissioner fails to see how disclosure of the information requested would place anyone at the remotest risk of identification, or provide any SOGC (Serious Organised Crime Group) with the remotest indication that it has been infiltrated, as claimed by Police Scotland," she said in her decision.

The Commissioner added that the authority needed to establish a link between disclosure and endangerment but she did not find that established in the circumstances of the case.

The civil appeal judges refused the chief constable's appeal and said they were satisfied that the Commissioner had given clear and intelligible reasons for her decision which were untainted by any of the faults asserted by the force.

Sunday Herald editor Neil Mackay said: "This is an important legal ruling which upheld the initial Scottish Information Commissioner judgement. We look forward to Police Scotland releasing the information."