The British government is considering a major expansion of its ability to record which sites people visit on the internet and who they email and speak to on the telephone, sources said today.
Police and the security services warn that criminals are becoming increasingly sophisticated in how they use technology to try to avoid detection.
Advances in mobile phone and internet technology mean government agencies fear their ability to gather the information they need to catch and prosecute organised crime and terrorists may be undermined.
The plans are at an early stage but options being considered as part of the Intercept Modernisation Programme (IMP) could include a database on which to put browsing histories, email traffic data and records of mobile phone calls.
Or it could involve passing laws which would require private companies that provide internet services to record that data themselves and give it to investigators when needed.
Officials stress that they are not seeking widespread powers to record the content of electronic messages sent from private computers or phone calls. This kind of intercept material cannot be used in court and requires the permission of a minister before it can be collected.
But background data about when electronic messages were sent, to whom and how, provides essential information about the movements and activities of criminal and terrorists, police say.
Few major prosecutions are brought without the use of communications data. Such information also allows detectives to get to the people behind major plots.
A source said the communications data “helps us get to the Mr Bigs who don’t get involved but are directing”.
But some investigations have already been affected by criminals who use technology to avoid detection, by plotting online through social networking sites or interactive games using the “chat” facility.
“Criminals are getting more sophisticated in using this technology and they are going to exploit it unless we do something,” the source said.
Plans to record more communications data (CD) will provoke fears of the “Big Brother” state.
Civil liberties campaigners say the public are already heavily monitored through CCTV and a giant database would raise fears for the security of the information.