POLICE have refused to say whether they have used spy powers against Scottish politicians, amid accusations spooks had infiltrated the SNP and the Government at the highest levels.

Police Scotland said the force would not discuss its use of the Investigatory Powers Act, which regulates spying on MPs and MSPs, after a former SNP MSP made serious accusations the British state was spying on nationalists.

It comes as former MSP Campbell Martin, who made waves earlier this week with his accusations MI5 agents had infiltrated and were controlling the SNP, made fresh claims in an interview with this paper that spying activity exploded with the creation of the Scottish Parliament.

In 1999, the SNP became the second-largest party in Scotland, the closest they had come to power in their existence.

Martin, who was an SNP MSP between 2003 and 2007 but was a Holyrood staffer from day one of the parliament, said the party began to attract increased surveillance from the security services from 1999 onwards.

Martin refused to identify those he believed to be spies, citing concerns for his safety, though claimed they worked as politicians, civil servants and within SNP HQ.

Speaking to The National, he said the belief the SNP had been spied on from the mid-20th-century onwards was common within the party, adding: “But when it started to build and began to become a threat to the British state, then they really infiltrated the party, they put people in.

“There is a difference between agents and assets and back then, in a sense, these people who listened at branch meetings and passed information back to the British state, the agents were people who were placed into the SNP to a specific task and the task was to undermine the cause of independence.

"That began to happen in ’99.”

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He added: “Some of the people in 1999 were relatively lowly, they were maybe staffers at headquarters, but they became, they moved into the higher echelons of the party in the intervening years.

“And that’s when they were able to influence party policy and direction and I would argue that’s one of the reasons why you have the party pursuing policies that are very unpopular instead of concentrating on independence.”

He went on: “After the 99 election, because the SNP was the official opposition […] we were allocated the whole second floor of the offices, the temporary offices at the top of the Royal Mile before they built the new Scottish Parliament.

“That’s when me and three or four other SNP MSPs we actually looked at some of the people on the same floor and thought, ‘these people aren’t nationalists, there’s something going on here.’

“And there were people from headquarters as well, who were appearing at the Parliament, that nobody had ever heard of.”

Martin’s claims are extraordinary, but they are partially backed by former health secretary Alex Neil who said he also believed the SNP had been infiltrated – but that spies had not influenced party policy.

Martin, who is no longer a member of any party, added: “I kind of laugh when I see the argument put forward by SNP loyalists, because what they’re saying then is, ‘we’ve not been infiltrated – we’re just crap.’”

'There are people in the SNP with friends in high places' 

Neil, who served at the top levels of the Scottish Government between 2012 and 2016, said: “It’s not a secret that the intelligence services were looking at the SNP in the early 40s when the party membership was measured in hundreds rather than thousands.

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“Probably, they’ve had some kind of monitoring facility since then. I think probably Campbell’s right. Clearly when we had 35 seats in 1999, that’s probably when they thought the threat was more serious.

“But I think the real threat would be when we gained an overall majority in 2011, where they would have really started to get worried and I think they’d have been very worried when it looked as if we might win the referendum.”

Neil, still a member of the SNP though notably critical of its current leadership, added: “I’m absolutely sure they’re still monitoring it [the SNP] and there will be people in the party and maybe even in the Government, either civil servants or politicians, who have friends in high places.”

But he rejected Martin’s claims the party’s position on issues such as trans rights and the doomed deposit return scheme, of which both men are critics, had been pushed by spooks.

“I think MI5’s much more subtle than that,” he added.

A spokesperson for Police Scotland said: “A Police Scotland spokesperson said: “We do not discuss our operational use of the Investigatory Powers Act.

“This area of policing is strictly controlled by legislation and national guidelines, where high thresholds of necessity and proportionality must be reached prior to any such activity.

“The public should be reassured by the significant safeguards which are in place and Police Scotland are regularly subject to scrutiny and independent inspection by the Investigatory Powers Commissioner’s Office.”

The Scottish Government declined to comment.

The SNP did not respond to a request for comment.

The Home Office, to which the Security Service reports, has a policy of not commenting on operational matters.