Privacy International is calling for UK consumers to take part in a 'Know your Data' campaign after warning that police and other agencies made hundreds of thousands of requests for data about individuals this year.
The surveillance watchdog said that people are generally unaware of this fact and don't know which organisations hold personal data about them and what this data covers.
The information requested includes telephone billing data, internet logs and customer details.
But according to Privacy International, this means that the data could relate to all telephone calls a person has made and received, who a person is in contact with, emails sent and received, websites visited, TV programmes watched, as well as personal financial and family data.
Government agencies such as the Scottish Drug Enforcement Agency, Customs and Excise, and the Financial Services Authority routinely ask for access to this type of data.
Privacy International also warned that, although warrants are needed to conduct almost all such surveillance in the UK, these are usually obtained from politicians or senior police officers, rather than from the courts.
The point of the Know your Data campaign, according to a statement on Privacy International's website, is to help UK consumers retrieve the information that is held about them.
"We hope that in so doing, all of us will learn a great deal more about this covert activity," it states.
"It is also likely that the exercise of our data protection rights will send a clear signal to communications providers and to government that people have a high regard for their right to privacy."
The Home Office has disputed the figures, according to the BBC, and insisted that new proposals are in hand to restrict the amount of data which public bodies can request, and to lay the process open to more scrutiny.
But organisations such as Privacy International are particularly worried that the government is eager to extend the powers of access to a greater number of public authorities under the Regulation of Investigatory Powers Act.
A public outcry last year led the government to draw back, but it is still consulting with industry about widening the powers.
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