Tim Farron to call for public protection from 'overreach by the state' after its imposition of 'blanket surveillance' on UK

A digital bill of rights should be established in Britain to ensure that basic online freedoms are protected from the "untrammelled power of the state", the Liberal Democrat president Tim Farron will say on Sunday.

The bill is a central feature of a motion, expected to be passed at the Lib Dem spring conference, which says that people need greater protections from "overreach by the state".

In a debate on surveillance, Farron will say that the laws governing surveillance are "not for purpose" as he calls for the appointment of a commission of experts to review the powers held by the state which has imposed "blanket surveillance on us all".

The debate on Sunday follows the announcement earlier in the week by Nick Clegg that he has commissioned a review into the surveillance techniques of Britain's intelligence agencies and the legal framework underpinning their work. The independent review is to be led by the Royal United Services Institute after the deputy prime minister failed to persuade David Cameron to establish a government review.

Farron, who will criticise politicians for their "muted" response to the revelations in the NSA documents leaked by the US whistleblower Edward Snowden, will make clear that he wants to go much further than Clegg. The Lib Dem president, who has tabled the motion with the campaigning MP Julian Huppert, will call for a modern version of the 1689 bill of rights.

Farron will tell the conference: "Our current system of regulation is insufficient to give us the protections that we need in this digital age. The time has come for us to establish a digital bill of rights.

"The 1689 bill of rights codified the basic freedoms which we still enjoy today. As we live more of our lives online, we deserve to know that we also enjoy a similar level of freedom in what we do in cyberspace."

The digital bill of rights would severely curb the work of GCHQ by blocking the "bulk collection of data" and ensuring that metadata or the content of communications could only be accessed if there were suspicions that an individual was involved in unlawful activity. Under the current rules, the intelligence agencies can harvest bulk data without approval. But the information inside the metadata can only be retrieved with the approval of the relevant secretary of state.

The Farron/Huppert motion also calls for the establishment of a committee of experts to review state surveillance, to review "all recent allegations" from the leaked NSA files and to scrutinise all the relevant legislation. This would include the controversial Regulation of Investigatory Powers Act 2000.

The motion also calls for the annual release of government transparency reports which would publish the number of user data requests made by the authorities.

Farron will say in the debate: "The motion before you seeks to address the untrammelled power of the state to roam through your digital life. We need to establish a commission of experts to review the powers the state currently holds. America has already vastly outpaced us in their reaction to this information. The time has come for Britain to catch up."

The Lib Dem president will criticise "supine" politicians who have criticised the Guardian for publishing information from the leaked NSA files. Farron will say: "In the UK we have had to endure the sight of senior politicians attacking the Guardian for having the temerity to try and inform the public of what is done in our name. For a prime minister who pretends to be so concerned with ensuring the freedom of the press he has a funny way of showing it.

"Fellow media outlets have even lambasted the Guardian for their brave revelations. They should be ashamed of themselves. Don't they realise that even the most hysterical distortions of the Leveson proposals are nothing compared to these threats to our freedom?"