Moray Council has revised its policy on covert surveillance, after discovering most officers authorised to command operations have never been required to use the power.
Councillors decided to reduce the number of officers commissioned to approve secret recordings from 11 to four at a meeting in Elgin yesterday.
The policy and resources committee heard that since the last check in 2012, only trading standards officers had seen fit to carry out operations.
The Regulation of Investigatory Powers (Scotland) Act 2000 sets robust controls for when surveillance can be performed.
Most commonly it is used to investigate cases of tobacco control, doorstep and consumer crime, illicit and counterfeit goods and age-restricted products.