LIE DETECTORS BLOG & NEWS: NADAC GROUP

Midlands pilots lie detector tests for sex offenders

Sex offenders in the Midlands will be required to take lie detector tests to see if they are still a danger to the public, the Ministry of Justice said yesterday.

The scheme, which will run as a pilot for three years, will compel sex offenders to answer questions over a 90-minute period, while a polygraph measures changes in breathing, heart activity and sweating, all of which are believed to be related to deception.

The results will be used to monitor risk levels and could lead to the recall of offenders who have been released into the community to prison. Information that comes out during the tests cannot be used as evidence in court.

The plans are being embraced by groups such as Barnado's, the children's charity, which said it warmly welcomed the government's decision. "This has the potential significantly to increase public confidence that sex offenders are complying with supervision," its chief executive, Martin Narey, said.

"Sex offenders trying to avoid re-offending will be helped by the knowledge that polygraph testing will expose any attempt by them to mislead their probation officer"
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Not everyone is so optimistic, not least because of the controversy regarding the tests' reliability.

"The real concern is whether these tests are accurate," said Edward Fitzgerald QC, a barrister who has represented numerous sex offenders. "A lot of the tests devised by psychologists in the past have turned out to be pretty unreliable and lie detector tests are not notorious for their reliability either."

Lie detector tests were first devised in 1917 by William Marston, a psychologist whose early version was widely criticised for its inaccuracy and was later replaced by more sophisticated versions.

Accuracy remains an issue, with the American Polygraph Association estimating 90% to 98% of results to be reliable.

There are also questions about the compatibility of lie detectors with fundamental principles in English law.

"There is a right against self-incrimination," says Fitzgerald. "These tests may be relevant in showing if you have breached a condition of your sentence or changed your attitude, but it's massively difficult to prove the negative that you are safe."

The Ministry of Justice states that the lie detectors will only be used "as part of an overall assessment as to the risk an offender presents" and may prompt further investigations.
The move towards a compulsory system follows an earlier voluntary pilot, in which fewer than half of those eligible consented to the tests. Of those that were tested, 79% made disclosures that were "relevant to treatment and supervision".