A woman who was alleged to have been sub-letting her social housing property had it taken away . . . after being presented with evidence from her own mobile phone.

According to a report presented to county councillors, the woman had initially denied subletting the property.

But as part of an investigation, officials presented her with 'communications event data' that supported an allegation that she was no longer living at her tenancy address.

And following that, says the report, a notice to quit was served and the property was recovered.

Officials say that without the 'communications event data' the case would not have proceeded.

And the case is among those highlighted in an annual report detailing the county council's use of Regulation of Investigatory Powers (RIPA) legislation by trading standards officers and 'shared anti-fraud service'.

The RIPA legislation has to be complied with whenever the council seeks to use directed surveillance and communications data.

And its use – as well as related council policies – has to be reviewed by councillors at least once a year.

According to a report presented to a meeting of the county council's cabinet on Wednesday (July 15), the county council was granted authorisation for directed surveillance twice in 2025/26.

As a result, trading standards officers carried out test purchases at a total of 19 premises – in two different operations – with vapes sold to a child volunteer on four occasions.

Meanwhile, 86 applications were made to obtain communications data in 2025/26 – which is higher than the 66 applications made in 2024/25.

The vast majority of the applications (81) were made by the shared anti-fraud service (SAFS), with the remaining five made by trading standards.

SAFS is a partnership between Hertfordshire County Council and a number of other councils in Hertfordshire and Bedfordshire.

Communications data can include the name and address of the holder of the communication account – or 'event' data, which includes logs of calls and messages and location data.

But local authorities cannot obtain the content of any of the communications, such as text messages or emails.

Highlighted in the report is the use of communications data by county council trading standards officers in order to investigate rogue traders.

And outlining how this information could be used, the report states: "In one alleged roofing fraud investigation, two males, one known and one unknown, cold called at a vulnerable resident's property and persuaded them to pay £6,000 for repairs which were not required and never completed.

"The known male was interviewed and provided brief details of the unknown male, insufficient to identify them.

"Communication data was obtained for the known male's mobile phone, which revealed a series of calls with a telephone number around the time of the offending.

"Online research revealed the telephone number to be used by a local roofer, matching the description of the unknown make.

"Communication data was then obtained for this mobile phone, which was registered to the roofer and placed him in the vicinity of the offending during the relevant times.

"Legal proceedings have now been initiated against both suspects for fraud offences as a result of the data obtained."

Presenting the report to the cabinet, deputy executive member for public health and community safety Cllr Allison Wren (Liberal Democrat, Harpenden Rural) highlighted the use of the legislation to investigate rogue traders.

And she highlighted the council's compliance with policies in place to ensure the legislation was being followed correctly.

"The report will detail how the powers have been used over the last year on several occasions," she said.

"It is used mostly by trading standards. And we have done that under covert intelligence to prosecute traders who are selling vapes and cigarettes to underage children, with very successful prosecutions and several more in the pipeline.

"And also, we have used it successfully to trace mobile phone data.

"The most recent one was a rogue roofer who had been preying on older people to get unnecessary roofing. And he was fined quite a lot of money recently.

"So we have used it very successfully. And I am delighted to report that we have had no breaches of the policies during the year."

In an exchange that followed the executive member for education, SEND and inclusion, Cllr Mark Watkin (Liberal Democrat, Nascot Park) acknowledged that it was "the sort of policy that strikes fear into many people that somehow we can be Big Brother and use it liberally and no-one is safe".

But he said he was pleased to see there was a control process over the use of this policy, "so that individuals don't feel that somehow we can just tap into their phone".

Following the debate, the cabinet approved the policies – which must be reviewed once a year – on directed surveillance and covert human intelligence sources; on the acquisition and disclosure of communications data; and for the use of social media in investigations.