Councils and police will continue to pass around sensitive data obtained using spying powers in the clear, after the government rejected calls to impose encryption.
The proposal was made in response to a Home Office consultation on the Regulation of Investigatory Powers Act (RIPA), which allows hundreds of public bodies to obtain phone and internet records.
Such data were accessed by authorities using RIPA powers 504,073 times last year. They are seen as a very powerful investigative tool, likely to record who a person has been in contact with and where they have been. Personal information such as phone numbers email addresses are included.
A single individual within each public body empowered by RIPA is responsible for obtaining the data from communications providers, which they then pass on to investigating officers. According to Duncan Campbell, who acts as an expert witness on communications data, it is usually delivered and forwarded without encryption.
"The almost invariable practice is to sent data, unencrypted, as CSV or XLS files. From [communications provider] to [public body], and then on to everyone else. Only one [communications provider] routinely provides some encryption when downloading data, but this is not preserved at the next stage," he wrote on the UKCrypto mailing list.
"As you might expect, the idea of generating and sending hashes or another form of digital signature to certify the integrity of the data has not found any hold."
Responding last week to suggestions "there should be a mandatory requirement for all RIPA applications, authorisations and material obtained to be encrypted", the Home Office said increased security is not feasible.
"It would be impractical to require all material obtained through the use of RIPA to be encrypted," it said.
"However, it is perfectly reasonable for members of the public to want reassurance that all appropriate steps are taken to protect material obtained through the use of techniques under RIPA.
"All relevant public authorities have in place a variety of security measures, including physical security measures, security procedures, staff vetting and training, to ensure that material is protected from improper disclosure."
Despite the assurances, concern over the security of communications data obtained under RIPA is likely to increase with its increased use, and increased capture. New police guidelines require detectives to consider obtaining phone or internet records during every single investigation and the forthcoming Interception Modernisation Programme will involve terabytes of data storage for communications providers.
Of course, some public bodies using RIPA powers use encryption as a matter of in-house policy. Many RIPA requests for communications data are made by the intelligence agencies, for example, who use only secure networks. ®