Don’t they already have that power?
Under the Regulation of Investigatory Powers Act (Ripa), police, secret agencies and a large number of public bodies have access to phone and email records and some web use.
However, not all service providers keep all the records and the legislation does not cover more modern forms of communication such as social network sites like Facebook or online phone call facilities like Skype.
What is the argument for doing it?
The Home Office argues that terrorists and serious criminals exploit all modern forms of communications and that the police and security authorities must have the capability to keep up.
Does it mean there will be a giant database storing the data?
No. Individual communication service providers will be responsible for recording and storing their own data but there will be no national database.
Who will the powers apply to under the new law?
More than 650 public bodies and, including some 474 local councils, and Government agencies have access under existing Ripa laws.
However, the Bill will replace Ripa for access to communications and ban all bodies expect for the police, security agencies and revenue and customs.
What do the critics say?
Civil liberty groups and backbench MPs from both the Conservative and Liberal Democrat parties warn it is an unnecessary intrusion in to people’s privacy and could be open to abuse.
Technology experts and service providers warn the practicalities of storing and filtering such information could be unworkable.
Will campaigners have a say on the proposals?
Although the Bill is being published today it will be scrutinised by a specially created parliamentary committee before passing through the normal legislative routes.
The committee is expected to hold evidence sessions where interest groups will be able to provide their opinion.