Britain's largest local authority, Birmingham Council, is to install a telephone lie detection system in an effort to combat benefit cheats. So how will it work?

Software that scans speech patterns is being trialled for weeding out benefit cheats.

In the first three months of a pilot scheme in Harrow, north London, that began in May, 173 housing benefit and council fraudsters were exposed, saving the council £110,000.

This success has led to Birmingham, the UK's largest local authority, being picked as the next council to use the technology, which is known as Voice Risk Analysis (VRA).

VRA is used only in conjunction with questioning by call operators who have been trained to detect deception, says a spokesman for the Capita Group, which owns the technology.

THE ANSWER
They detect inaudible fluctuations in the human voice, consistent with stress brought about by lying
It works by measuring "micro-changes" to the frequency of the human voice and relaying to the operator, in real time, the level of risk that the speaker is being deceptive.

At the start of the conversation, the software takes the caller's normal voice as the benchmark and accounts for the possibility that changes may be caused by nerves.

"Just because someone gets stressed or uncertain about something does not mean they will be classed as high risk," says the spokesman.

Stealing

If the caller is deemed by the operator to be low risk, using the test results to support their own judgement, they are fast-tracked and avoid more rigorous vetting.

Those deemed to be at higher risk of lying must supply further evidence to support their claim.

There's no way you can tell from a single telephone call whether someone is lying

Bruce Burgess
Polygraph expert
A spokeswoman for the Department of Work and Pensions, which is partly funding the trials, says: "The vast majority of people who receive benefits are genuinely entitled to them.

"However, there is a minority who are intent on stealing money from those who need it most.

"This technology-based process aims to tackle these fraudsters while speeding up claims and improving customer service for the honest majority."

It is already used in the insurance industry as one of many fraud detection techniques, although representatives for the industry say it is deployed sparingly.

"They are used in exceptional circumstances, not routinely," says a spokesman for the Association of British Insurers. "Only a handful of insurers would use them and only when there are strong grounds to suspect fraud, and as part of a whole package of fraud protection measures."


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But the TUC has voiced concerns about its use on benefit claimants, believing that innocent but nervous people could have their claims delayed or even rejected.

Conventional lie detector systems, called polygraphs, pick up on changes to breathing, sweat glands, heart and pulse.

And Bruce Burgess, a "professionally trained" polygraph examiner, says telephone lie detector systems are about as reliable as tossing a coin.

"There's no way you can tell from a single telephone call whether someone is lying. Before a polygraph test we have to prepare a subject for hours so they trust the examiner and trust the test.

"Otherwise even if they are being truthful, there could be a reaction. The key is to have no surprises."

But telephone tests could work well as a deterrent, he says, because if people think they're being tested, they're less likely to make false claims.