Spying powers have been used by Hammersmith and Fulham council nearly 60 times in five years – including on three occasions to catch out its own staff.
The controversial Regulation of Investigatory Powers Act (RIPA), introduced in 2002 to accusations it was a 'snoopers' charter', was originally intended to allow public bodies to use surveillance in a bid to fight crimes such as terrorism and paedophilia.
But since 2005, the council has made 56 so-called RIPAs, including for minor offences like fly-tipping and, on two occasions, to investigate an accusation of brick-throwing on a council estate.
And, following an application under the Freedom of Information Act, the Chronicle can reveal that three times the council has targeted its own staff with the act, which allows authorities to bug and follow people or tap their communications.
In April 2007, it conducted 'visual surveillance of employees suspected of fraudulent activities'.
In May 2008, it watched an employee 'claiming to be medically unfit to attend duties'.
And the following month, it used the same technique on an employee 'suspected of benefit fraud'.
A council spokesman refused to disclose the results of its investigations.
Common RIPAs made by the council include for criminal damage (13 times), drug dealing (11 times) and fraudulent use of disabled blue badges (six times).
The act was introduced to recognise the growth of technological communications like the internet, which is increasingly seen as a prime tool for terrorists.
But it also gives public bodies like councils, the ambulance service and the Office of Fair Trading powers to prevent disorder, crime, and, among other things, protect public safety.
Critics argue it is a threat to civil liberties and say the act was pushed through Parliament without proper debate.
But Hammersmith and Fulham Council insists the powers are vital to keep crime down and said the act is never used disproportionately.
Lyn Carpenter, director of residents' services, said: "We make absolutely no apology for using RIPA surveillance to investigate those people who are suspected of breaking the law or defrauding the council.
"We shall continue to use this important tool in order to drive down crime in the borough and we have safeguards in place to ensure that it is used appropriately and proportionately.
"The council is committed to making the streets of Hammersmith & Fulham drugs free and regularly uses RIPA to investigate drug-related allegations. If verified the information is passed to the police for follow-up action. If drug dealing is not verified other antisocial behaviour occurrences are often uncovered."
Since 2005, RIPA applications have been made for:
CRIMINAL DAMAGE: 13 TIMES
DRUG USE: 11 TIMES
DISABLED BADGE FRAUD: SIX TIMES
DISORDER: FIVE TIMES
NOISE: THREE TIMES
COUNCIL EMPLOYEES: THREE TIMES
BRICK THROWING: TWICE
RACIST ABUSE: ONCE
ANTISOCIAL BEHAVIOUR: ONCE
THEFT IN COUNCIL BUILDING: ONCE
DOOR-TO-DOOR SELLING:: ONCE
CRININAL DAMAGE AND DRUGS: ONCE
OBSTRUCTING HIGHWAY: ONCE