A council breached surveillance rules after it set up hidden cameras in a home using controversial “snooping powers”.
Cambridge City Council used the powers – designed to tackle terrorism – to put secret cameras in the home of a woman who claimed her partner was seriously physically abusing her.
Council chiefs have admitted it was “intrusive surveillance” and have tightened up procedures for using the Regulation of Investigatory Powers Act (RIPA) since this incident in February 2010.
But ahead of a meeting on Monday at which the use of RIPA will be discussed, campaigners claim the use of secret cameras by a council highlights the dangers of giving the powers to town halls.
Nick Pickles, director of privacy and civil liberties campaign group Big Brother Watch, said: “It highlights just how weak the safeguards around these powers are that a council thought it had the power to plant secret cameras in someone’s home when they absolutely do not.
“The public should know who signed off on this operation and what on earth they thought they were doing. Did they take legal advice or were they making it up as they went along?
“Serious crime like this is for the police to investigate and not Cambridge City Council.”
A report to Monday’s city council meeting will tell elected politicians the authority is “very sparing” in its use of the powers and has authorised their use just once since October 2008.
The council report on the secret cameras in a home said: “The authorisation on that occasion was for directed surveillance by covert CCTV as part of co-operation with a police investigation into incidents of serious domestic assault.
“Covert CCTV was installed in the victim’s home with her full co-operation to gather evidence against the perpetrator.
“While the officers were satisfied the surveillance was appropriate in supporting the victim and in gathering evidence of serious criminal behaviour, the police, rather than the city council, should have authorised the surveillance.
“Technically, this amounted to intrusive surveillance, which the police can authorise, but the council cannot.”
The report said “guidance has been strengthened” and from next month, councils will have to gain permission from a magistrate to conduct covert surveillance.
Cllr Tim Bick, leader of the city council, said: “The event happened in February 2010 and was carefully reviewed in public a year ago, resulting in the introduction of specific legal supervision any time an application is made for covert surveillance, which the Office of Surveillance Commissioners has expressed satisfaction with.
“This will be reinforced by the new legislation, which as Liberal Democrats we welcome and have championed.”
Councils in the region have used the legislation, which privacy groups refer to as “snooping powers”, 75 times in the last three years, a report by campaign group Big Brother Watch revealed in August.
Cambridge City Council was not included in the report. The law was changed earlier this year to stop councils using the powers without a magistrate’s approval.