Figures show anti-terror legislation used a number of times for minor offences

The Regulation of Investigatory Powers (Scotland) Act 2000 (RIPSA), designed to catch terrorists, has been used against underage sunbed users and dog walkers.

Local authorities have used the laws to initiate over 501 clandestine investigations since 2012 according to data obtained by BBC Scotland.

While the act has been used to deal with drugs and prostitution, it has also been used in irrelevant situations.

The act provides that its powers may be used to stop or detect crime or to prevent disorder, to protect public health and to act in the interests of public safety.

It permits public authorities to use hidden cameras against people suspected of breaking the law and to follow as well as bug them.

However, campaigners have said the powers have been misused to investigate less serious offences, with a number of spying operations leading to no penalty or conviction being imposed.

Since 2012, South Ayrshire council has allowed investigations concerning underage sunbed use as well as dog fouling and the unlicensed sale of fireworks.

One third of the investigations were authorised by Dundee city council. Of these 137 operations, half concerned excessive noise, counterfeit cigarettes as well as fraudulent use of blue badges and circumstances where people have faked personal injury.

Changes relating to surveillance of lawyer-client discussions have been approved by the Scottish parliament will come into effect on Monday.

These changes will ostensibly tighten the authorisation arrangements for requesting surveillance of such discussions.

Emma Carr, director of campaign group Big Brother Watch, said: “The public will want surveillance powers to be used when it is right and necessary.

“However, from almost the moment that the legislation was passed, hundreds of public authorities clambered to have access to these incredibly useful powers.

“This, alongside a lack of post-legislative scrutiny over more than 10 years, resulted in these powers being used for arguably less serious crimes.”

The data also indicated that the use of the laws has declined since 2012 – the year in which judicial approval became necessary for requests of communication data.

Ms Carr added: “If these powers are being used, especially the more intrusive of the powers, and there is no arrest or prosecution, then questions should certainly be asked as to why this is the case.

“This is why it is concerning that members of the public who have been placed under surveillance aren’t told that this is the case, meaning that they will be unable to seek redress if the surveillance has turned out to be unnecessary.”

In addition to councils, the Scottish Prison Service used the powers under RIPSA 20 times, NHS National Services Scotland used it three times,Transport Scotland used them once while the Scottish Environment Protection Agency used them four times and Marine Scotland five times.

Police Scotland neither confirmed nor denied to BBC Scotland whether it had used the powers in the last three years.

It said: “If the police service were to either confirm or deny that any other information is held, other covert surveillance tactics will either be compromised or significantly weakened.

“To reveal exact detail of the number of Ripa or Ripsa applications on any specific subject area would reveal covert investigative activity that may or may not have taken place and would highlight to terrorists and individuals intent on carrying out criminal behaviour, covert policing activity.”

But a recent report from an independent watchdog established under theRegulation of Investigatory Powers Act 2000, the Interception of Communications Commissioner indicates the single force had 19,390 authorisations relating to communications data granted in 2013.