An intelligence watchdog inquiry into the intercept activities of UK spy agencies will take evidence from members of the public in the wake of widespread concern over ''snooping''.
Parliament's Intelligence and Security Committee (ISC) announced it will broaden its investigation into whether the laws on intercepting private communications are adequate in the internet age amid fears over the " impact upon people' s privacy as the agencies seek to find the needles in the haystacks".
Earlier this year, an ISC inquiry found GCHQ did not use the US internet monitoring programme in order to circumvent UK laws.
The committee said that 197 counter-intelligence reports generated by GCHQ through the US Prism programme - exposed by former intelligence analyst Edward Snowden - had been properly signed off by ministers.
But the furore over the activities of agencies on both sides of the Atlantic prompted the committee to mount a wider investigation into the legislative framework governing the intercept of communications.
ISC chairman Sir Malcolm Rifkind said: " The Intelligence and Security Committee of Parliament announced - as part of its statement on Prism, issued in July - its intention to do further work on the legislation which governs the security and intelligence agencies' access to the content of private communications, including to determine whether the relevant Acts of Parliament are still 'fit for purpose' given the developments in information technology since they were enacted.
" In recent months concern has been expressed at the suggested extent of the capabilities available to the intelligence agencies and the impact upon people' s privacy as the agencies seek to find the needles in the haystacks that might be crucial to safeguarding national security.
"There is a balance to be found between our individual right to privacy and our collective right to security. An informed and responsible debate is needed. The Intelligence and Security Committee of Parliament has therefore decided to broaden the scope of its forthcoming inquiry to consider these wider questions, in addition to those relating to the existing legislative framework.
" In addition to the classified information that only the ISC has access to, the committee will also be inviting written evidence more broadly, including from the public, to ensure that the committee can consider the full range of opinions expressed on these topics. Once it has considered those written submissions it will also hold oral evidence sessions, some of which it expects to hold in public.
" The committee is currently focussed on its detailed investigation into the security and intelligence agencies' actions in relation to those suspected of murdering Drummer Lee Rigby in Woolwich. It will provide further details in relation to the inquiry announced today in due course."
The intercept activities of the agencies are governed by three pieces of legislation: the Intelligence Services Act 1994, the Human Rights Act 1998, and the Regulation of Investigatory Powers Act 2000.
But the committee said parts of the legislation were expressed only in ''general terms'', adding that GCHQ had found it necessary to put in place ''more detailed policies and procedures'' in order to ensure that it complied with human rights laws.
Nick Pickles, director of Big Brother Watch, said; "This is a welcome step forward given the widespread concern that Britain's surveillance laws are not fit for purpose, having been written before Facebook existed and when few people had internet access.
"However, such a debate cannot be allowed to take place behind closed doors and without pressing questions being asked about the legal justification for what we know to be already happening at GCHQ and elsewhere.
"The ISC's reputation is increasingly at stake given recent failures to get to the bottom of controversies and this work must be to the highest standards of independence, objectivity and transparency if it is to command Parliamentary or public confidence."
Shami Chakrabarti, director of civil liberties campaigners Liberty, said: "This watchdog makes friends and does not always bark in the night.
"Some will say better late than never, others fear a tactical whitewash to calm public concern.
"It's certainly significant that the committee feels compelled to dig a little deeper but that's no substitute for much broader public and political debate.
"Public safety requires proportionate surveillance but the watchers need watching too."