A pilot programme that required high-risk sex offenders to undergo regular polygraph tests has had a significant impact on cutting re-offending, according to organisers.
Following the apparent success of the pilot, the government is now planning to roll out mandatory lie-detector tests for high risk sex offenders across England and Wales.
The study was carried out in the East and West Midlands between April 2009 and October 2011.
More than 600 sex offenders who were freed on licence were tested every six months in an attempt to find out if they had breached the terms of their release.
The pilot identified that offenders were two to three times more likely to admit to potential breaches of their licence, often before they had even undergone the test procedure.
Those in charge of the study believe the pilot prevented numerous new offences from being committed.
Pilot organiser Professor Don Grubin said: "Successes of course are always invisible, but I have no doubt that a number of offences were prevented in the course of the pilot.
"On some occasions it's offenders who have been recalled to prison who said if they hadn't been recalled when they were, they would have reoffended."
In one example, an offender who had previously assaulted an eight-year-old girl, groomed through friends of his partner's children, was found to be lying about contact he had with his partner.
Authorities discovered he had booked guest house accommodation where he planned to meet his partner and her children. He was immediately recalled to prison.
Probation Minister Crispin Blunt says the tests will help manage offenders In another case, a man released on licence for rape and attempted rape, admitted in his pre-polygraph interview that he had masturbated outside near a public footpath and had been in contact with other sex offenders. He was also taken back into custody.
Polygraph tests measure blood pressure, heart rate, breathing and levels of perspiration. These vital signs display subtle changes when someone is deliberately evasive and polygraph experts can usually determine if that person is lying.
Studies have shown that polygraph tests are accurate around 85% of the time.
Ministers believe they are particularly effective in helping offender management teams determine whether the likes of paedophiles and rapists are complying with the terms of their licence.
Probation Minister Crispin Blunt said: "I think it's going to be an important tool for probation officers in managing sex offenders on licence in that second part of their licence when they've been released from custody and are liable to recall to prison if their behaviour gives any cause for concern."
An offender can be immediately returned to prison if the lie detector test, coupled with other information, indicates they have broken their licence conditions.
The government is now planning to introduce legislation in parliament to allow the Midlands pilot to be rolled out across England and Wales.
