The test that could trap sex offenders

HARDLY a day goes without the cases of sex offenders cropping up in the news. There might be relatively few of them but the fear and loathing they cause, particularly paedophiles, is almost in inverse proportion to their numbers.

Sex offenders qualify for parole like any other category of criminal and at any one time there are a small but significant number of convicted sex offenders out on parole.

Short of locking sex offenders up for the rest of their lives - a solution which even tough-talking Home Secretary John Reid would probably not favour - what is the best way of ensuring this type of offender is not tempted to re-offend?

Newcastle consultant Don Grubin, a professor of forensic psychiatry, is convinced that he knows how to improve supervision and control of sex offenders. Since 2001, Professor Grubin has been conducting an experiment involving electronic polygraphs, better known to fans of old B-movies as lie detectors.

From small beginnings involving just 30 sex offenders, the experiment now covers hundreds of offenders in ten probation service areas in England. One of those areas is Northumbria, and it is clear that probation officers who work on Wearside, Tyneside and in Northumberland approve of the scheme.

A spokesman for the Northumbrian Probation Service recently told The Northern Echo that the polygraph testing had proved very useful in monitoring sex offenders.

A full report about the results of the national polygraph pilot, written by Prof Grubin, is currently with Home Office ministers. And while the Newcastle University don will not disclose its contents, it is clear that he believes there is evidence that the use of polygraphs is a vital tool in the supervision of offenders.

Prof Grubin believes that the modern polygraph is around 90 per cent accurate, making it very difficult for offenders to lie about illicit behaviour or thoughts.

Using highly sophisticated sensors attached to the subject's chest, abdomen, hand and arm the machine measures up to 21 different physical indicators, including cardio-vascular activity and sweating. A digital readout allows the operator to pick up signs that the subject is not telling the truth.

Last year, the Independent newspaper carried provisional results of the trial which showed that 85 per cent of offenders either failed the test or disclosed information relating to their reoffending. Within this group about two-thirds disclosed information that was not known to their probation officers.

Frustratingly for those involved in the trial, the Home Office has not indicated whether the project is to be extended beyond the end of this month. Unless the Home Office backs an extension to the scheme, pending the introduction of legislation which would be needed to allow the tests to become mandatory for offenders, probation officers will have to go back to their old way of working.

Polygraph examinations, which last from 90 minutes to four hours, are conducted at a special centre in Newcastle.

Shay Addison, the Australian psychologist who conducts polygraph tests on offenders in Northumbria, Greater Manchester and Lancashire and has trained the five polygraph operators operating across the country, says the machine does produce results.

"One child sex offender disclosed he would always walk where he knew there would be children, increasing the risk of reoffending. Another who was living in a probation hostel revealed that he came downstairs every morning to collect the newspaper from a 12-year-old paper girl.

"We have picked up more serious things, including men who have admitted after polygraph testing that they are thinking about reoffending. It is also useful in picking up men who still have an interest in children, even if they deny it."

Prof Grubin, who was born in the United States but has worked in the UK since 1975, says many people associate polygraphs with Cold War spy films.

But modern polygraphs are widely used by police forces in America and evidence from polygraph examinations are valid in the courtrooms of around 20 states.

He says that polygraphs have been used in the interrogation of suspected Islamic terrorists at the Guantanamo Bay detention centre, as well as in counter- espionage. Polygraph tests are also routinely used in the supervision of sex offenders on parole in the US. The big difference is that in the US the tests are compulsory.

Currently, UK offenders can decline to take polygraph tests. They would become mandatory if legislation which was mentioned in the Labour Party's last election manifesto is given Parliamentary time by the Government.

Prof Grubin believes it is very hard to deliberately fool the polygraph, although it is known that spies are trained in techniques which can make it more difficult to tell when someone is lying.

Apart from forcing offenders to disclose information about their behaviour or thoughts, simply setting up the polygraph and going through the preparatory tests tends to loosen tongues.

"We often describe the polygraph as a truth facilitator as well as a lie detector. In the time before the test begins, people will often talk more freely. The polygraph focuses the mind," he says.

How my lie caught me out

I FELT a little apprehensive as the polygraph operator prepared to wire me up after I agreed to take a lie detector test at St Nicholas Hospital in Newcastle.

Psychologist and polygraph operator Shay Addison asked me to sit on a rubber mat with built-in movement sensors, then she attached thick concertina-like rubber bands around my chest and abdomen designed to identify any significant changes to breathing patterns.

A blood pressure cuff was the next sensor to be attached to my right arm, giving the operator additional information about the body's reaction to questions. And the next step was to attach two sweat sensitive sensors to the fingers of my left hand. They would pick up any changes in my body's resistance to electrical conduction.

All of the sensors are connected to a laptop computer which displays the information digitally on a screen rather than relying on a battery of pens racing across white paper.

Shay asked me to pick a number from one to six. I chose six and she asked me to draw a large number six in the centre of a sheet of white paper and put a box around it. She wrote one to six on the same sheet of paper, with an additional number seven.

Then the test began. Trying hard not to blink or squirm, I listened carefully to the questions.

Shay asked me to reply "no" to every question and then asked me - in turn - whether I had written the numbers down.

While she worked her way through the numbers I can remember thinking that the test would be a failure, because I didn't feel any different as I approached the number six. But I admit that I then felt a vague sense of heightened tension and then release as Shay asked me to deliberately lie about number six.

Freeing me from my constraints, Shay pointed to clear cardiovascular changes just before she reached number six. She could also see an increase in sweat. She says the brain recognises certain 'danger' questions and triggers physical changes in the body which are largely involuntary.

Shallow breathing is another tell-tale sign that the subject is lying but in all there are 21 different responses which can be measured.