Polygraph tests are being used more regularly by police forces as part of their strategy in managing sex offenders within the community.
Lie detector tests and sex offenders
It was hoped that use of these detectors would lead to offenders being more honest and disclosing significant information. Examples of information disclosed to the police included access to children and association with other paedophiles.
The results from the tests seem to be based predominantly upon the offenders belief that the test could catch them out rather than the ability of the test to detect lies. Thus a self fulfilling prophecy. I know I will be caught so I’ll ‘fess up’. Because the offender thinks the programme works they are more likely to be honest. In fact some of these confessions took place immediately before the test was undertaken.
Do lie detector tests work?
Further studies have shown that general polygraph tests correctly have identified 85% of guilty individuals. However where the figures are not so clear are the number of innocent people who have been wrongly classified as lying. A study by the British Psychological society suggests this figure may be between 12 and 47%.
Innocent people may fail because they are trying to cover up legal activity that they are ashamed of, or simply they will not be believed despite their innocence. These anxieties can cause the emotional arousal that can be interpreted by the operators as lies.
The truth about polygraphs is that they are not 100% reliable for detecting deception and once offenders realise this, the effectiveness of this technique in terms of increasing disclosure is likely to disappear.
Can you beat a lie detector test?
Further a cursory google of ‘how to beat a lie detector’ can reveal techniques to beat the test by use of self imposed pain and mental training/meditation. A motivated high risk offender could beat the polygraph with a relatively small amount of research. It’s worth reading the story of Floyd Buzz Fay, an innocent man convicted of murder, on the basis of a failed polygraph test. He taught fellow inmates to deceive the polygraph. America, of course, but the principle is relevant.
There is something else to be cautious about. If polygraphs are rolled out on a large scale it would undoubtedly be carried out by less well trained staff than in controlled small scale experiments. Police are already highly experienced in controlling interview environments to give them the answer they want. Imagine how much more of an effect you could get if all you had to do was to raise your voice or change your body language to induce an already nervous subject to register a positive result.
There is surely no room for this when a person’s liberty is at stake, regardless of who that person is or what they have been accused or convicted of.
Max Saffman – sexual offences solicitor
Max Saffman, solicitor at Olliers, specialises in advising clients in all aspects of offences under the Sexual Offences Act 2003 and preceding legislation including notification requirements under the Sex Offenders Register, Sexual Harm Prevention Orders (SHPOs) and Sexual Offences Prevention Orders (SOPOs). For an initial consultation feel free to contact on 0161 8341515, email firstname.lastname@example.org or click here to send us a message.