Polygraphs put to the test

Hi-tech lie detectors could soon be in use following a consultation by the National Offender Management Service on mandatory polygraphy for sex offenders.

The National Offender Management Service is proposing to operate a three-year pilot of mandatory polygraphy to help in the management of sex offenders.

The pilot, due to begin in April 2009, will determine if the polygraph can help in the management of sex offenders. The results of the pilot will be evaluated before a decision is made by Parliament as to the future of polygraph testing for sex offenders on a national basis.

A polygraph is a device that measures changes in breathing, heart activity and persiration, all of which are believed to be related to deception. The polygraph will be used to monitor whether offenders are engaging in risky behaviour or behaviour that puts them in breach of their licence conditions. For each offender subject to polygraphy requirements, risky behaviours would be identified that might indicate they were about to return to offending. A polygraph test would then be applied at regular intervals to test the offender’s responses to questions about those behaviours.

Evidence from the polygraph would be used as part of an overall assessment as to the risk an offender presents to the public or to specific individuals.

If an offender failed a polygraph test, this on its own would not be used as the basis of proceedings such as breach of licence or recall to prison. However, such evidence might prompt further investigations which in turn might provide evidence of a breach of the offender’s licence conditions.

Sexual offenders are routinely polygraphed in many states of the US and it is often a mandatory condition of probation or parole. In Texas, a state appellate court has upheld the testing of sex offenders under community supervision and has also upheld written statements given by sex offenders if they have committed a further offence with new victims. These statements are then used when a motion is filed to revoke probation and the probationer may then be sentenced to prison for having violated his or her probation.

A significant number of Federal appeals courts have also upheld polygraph testing for Federal probationers as well. In 2007, polygraph testimony was admitted by stipulation in 19 states, and was subject to the discretion of the trial judge in Federal court.

Also in the US, the Department of Defence, Department of Justice, Federal Bureau of Investigation (FBI), US Immigration and Customs Enforcement (ICE), and all the intelligence agencies routinely conduct polygraph examinations as part of the hiring process.

The greatest misconception of the polygraph is that it’s 100 per cent accurate. Its developers and law officials often claim that it is between 90 per cent and 95 per cent accurate. However, a survey of psychologists taken in 1997 described the polygraph as a little over 60 per cent accurate.

Polygraph condition

In most European jurisdictions, polygraphs are still not considered reliable evidence and are not generally used by police forces. However, in any lawsuit, an involved party can order a psychologist to write an opinion based on polygraph results to substantiate the credibility of its claims. An example of this practice would be a rape trial in which the defendant tries to fortify their testimony by submitting themselves to a polygraph session.

In the UK, Sections 28 to 30 of the Offender Management Act 2007 enable the Home Secretary to insert a ‘polygraph condition’ in the licence of certain sexual offenders who are being released from prison. A polygraph condition would require the released person to undertake polygraph tests as specified in the Act in order to contribute to the safer management of that person in the community.

The Act also makes provision for the Home Secretary to set rules regarding the conduct of polygraph sessions. The rules may, in particular:

•Require po