Anjana Ahuja asks if polygraphs - or lie detectors - should be used to monitor sex offenders in the UK, when it can reportedly take just five minutes to learn how to beat them.
After successful trials, where sex offenders made more disclosures after their use, legislation was brought in to implement polygraph testing for those with a high risk of reoffending. The tests are now being introduced nationally with members of the police undergoing polygraph training.
However, interpretation of the science is under dispute and, according to critics, the test is not only unreliable, but it can easily be beaten. Two of the United States' most notorious serial killers both passed polygraphs. Former US policeman Doug Williams, who has been teaching people how to beat the detector for decades, claims it can be done in just five minutes. He is currently awaiting trial in the United States accused, according to the FBI, of "training customers to lie and conceal crimes during polygraph examinations".
Science columnist for the Financial Times, Anjana Ahuja, argues that the introduction of polygraphs for sex offenders in the UK requires further ethical scrutiny and academic oversight..
The programme includes interviews with Doug Williams, psychologist Professor Chris French, polygraph historian Ken Alder, Jeremy Wescombe from the British Polygraph Association, Professor of forensic psychiatry Don Grubin, Professor of criminal justice Phil Rumney and DC Andrew Tinker from South Yorkshire Police, one of the first police forces to trial the use of polygraphs with sex offenders.
Producer: Sue Nelson
A Boffin Media production for BBC Radio 4.