Benefit claimants will face lie detector tests and will lose benefits for a month if found guilty of fiddling the system under proposals unveiled by Gordon Brown on the eve of today's Queen's speech.

The "one strike and you're out" proposal is contained in a tough summary of the speech released yesterday by the Cabinet Office. The government is also proposing to give the public clearer information, mainly via the internet, on how criminals are sentenced in local courts. Communities are to be given a bigger role in deciding what form of community punishment local criminals should be forced to undertake.

The proposals mark a break by the prime minister from his focus on the economic crisis for the past five months and suggest he knows he needs to broaden his political agenda if he is to claw back lost votes.

The introduction of a lie detector test for benefit claimants is the most striking shift to a more populist programme, similar to Tony Blair's respect agenda.

So far, 25 local councils administering housing benefit to 500,000 claimants are using "voice risk analysis technology" to test whether a claimant is providing false information.

The government introduced the technology in Harrow, north-west London, last year, but says it plans to make the technology available nationwide. In the first three months of using the technology Harrow saved £300,000, suggesting that levels of benefit fraud may be higher than government estimates. Ministers are cracking down on benefit fraud even though it is officially at its lowest recorded level, down 66% since 2001.