POLICE Scotland is facing fresh questions over its covert law enforcement strategies after being forced into confirming the recruitment of 759 informants.

The single force finally published the figure, which amounts to over 20 covert human intelligence sources (CHIS) a month, after a failed court bid to stop the information from being released.

However, campaigners yesterday demanded to know if any of the informants had snooped on protest and campaign groups.

In 2009, it emerged that officers claiming to be from Strathclyde Police had tried to infiltrate environmental group Plane Stupid.

Detectives offered activist Tilly Gifford cash for information, but she refused, recorded the conversations and exposed the approach in a national newspaper.

At a UK level, the Metropolitan Police has also been severely criticised for embedding undercover officers into peaceful protest and campaign groups.

Under freedom of information legislation the Sunday Herald asked Police Scotland in January last year for the amount paid to CHIS, a copy of all standard operating procedures on the practice, as well as the number of covert sources since the force was formed.

The force answered the first two questions – total spend in the first two years had come to nearly £400,000 – but refused the final request.

Police Scotland believed publishing the number could help organised crime groups and deter informants from coming forward in the future.

However, the Scottish Information Commissioner, which adjudicated on the dispute, ordered disclosure after rejecting the force’s arguments: “The Commissioner considers 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 SIC added: “The Commissioner fails to see how disclosure of the information requested would place anyone at the remotest risk of identification, or provide any SOCG [Serious Organised Crime Groups] with the remotest indication that it has been infiltrated, as claimed by Police Scotland.”

Police Scotland, which is led by chief constable Phil Gormley, disagreed with the ruling and challenged the SIC in the Court of Session. However, the civil appeal judges rejected the appeal.

On Monday, after resisting disclosure for over a year, the force confirmed 759 CHIS had been recruited between April 2013 and January 2016.

Recruiting informants is considered to be a vital and legitimate policing tool that has helped solve crime. Many of the CHIS will have assisted on a short-term basis.

However, campaigners have asked for assurances that CHIS are used to target criminals and not for wider political reasons.

Gifford said: "Speaking as one of many people affected by police intrusion in Scotland, I wonder how many of these spies are sent to damage legitimate campaign groups dedicated to positive social change? Against the backdrop of there being no proper inquiry into undercover police abuses in Scotland, this hidden information needs to be made public by Police Scotland."

Labour MSP Neil Findlay said: "Covert intelligence gathering is a legitimate way of finding out information on serious and organised crime, but the UK Government's undercover policing public inquiry has just revealed that since 1968 over 1000 different social justice and political campaigns have been monitored using covert methods.

“Now we have to establish if such organisations are being monitored by Police Scotland. We cannot in a so called free democracy have the police treating such groups like criminals.”

Donal O'Driscoll, who is an Undercover Research Group campaigner, said: “759 informers is a significant number and indicates that Police Scotland continues to rely heavily on informers and undercover police. Given their history of spying on campaigns groups, it would be highly surprising if this number didn't include those paid to inform on protestors. Police Scotland need to come clean on just how many campaigns and protest groups have been targeted in this way.”

The Sunday Herald asked Police Scotland if the force wanted to comment on the figures, or whether any of the informants were linked to campaign and protest groups.

Detective Superintendent Paul Donaldson said: "The use of Covert Human Intelligence Sources (CHIS) is a tactic which is successfully used proportionately and legitimately to support the police service in keeping the people of Scotland safe. It is a well-established, highly-regulated and independently-scrutinised tactic."