The Utility of the Polygraph with Sex Offenders in England

The history of the use of the polygraph with sex offenders is well documented and it is considered to play a beneficial role in confronting denial amongst sex offenders, monitoring their activities in the community and gaining a more comprehensive understanding of their historical sexual interests and behaviours.

In order to pursue the use of the polygraph with sex offenders in the UK, a three year pilot study was undertaken in designated Probation areas in England. Offenders participated on a voluntary basis and included men who were subject to Probation Orders or Licence conditions. This was the first extensive pilot study and it followed on from smaller, earlier studies to achieve a more comprehensive understanding of the polygraph’s utility in working with convicted sex offenders. A description of the research and evaluation of the findings are detailed in Grubin (2006) and are not recapitulated here.

The present survey-based research was undertaken shortly after the three year pilot was concluded in June 2006 as this was judged to be the most opportune time to obtain informed views from sex offender professionals in England who had acquired some exposure to the polygraph within the course of their work. It is notable that in the two years since then and the publication of this article no further research or regular employment of the polygraph has been carried out in the UK within the sex offender field.

The structured survey the present authors employed sought opinions from professionals working with sex offenders in England on various questions including whether they thought the polygraph should continue to be used voluntarily or be introduced on a mandatory basis. The survey was undertaken in light of the fact that the voluntary use of the polygraph was, by this time, suspended pending a Government review.

It was recognised that whilst some of the respondents would have had direct knowledge of the use of the polygraph, many others would be less informed about its use though perhaps knowledgeable of the National scene or in communication with colleagues in areas of England where the polygraph has been employed. The survey was sent to 953 professionals known to the authors to be involved in sex offender work in England. They consisted of probation officers, groupwork facilitators, social workers, NSPCC workers, psychologists, psychiatrists and others. Responses were obtained from 275 of these professionals.

Amongst the responding participants the majority, 197 (71.6%) reported that they had never had any direct involvement with the polygraph in the course of conducting their work. This was unsurprising in consideration of the fact that only 10 of the 42 probation areas in England had participated in the principal Pilot Study and the earlier trials were conducted in these same areas. Further, sex offender professionals who had no working affiliation with the National Probation Service, even in geographic areas where the polygraph was being employed, would similarly have acquired, at best, only indirect knowledge of its use. Only 78 (28.4%) of the participants within the study had developed more informed views, e.g. some direct experience of the use of the polygraph with sex offenders.

Further to our survey analysis the participants who had been involved in using the polygraph in their work expressed supportive views with regard to continued polygraph employment with convicted sex offenders. Indeed, 72 (92%) of these individuals opposed the withdrawal of the polygraph’s voluntary use and, more conservatively, 45 (58%) of these professionals expressed the view that its use should be mandatory with convicted sex offenders.

Further, there were a number of other findings in the analysis of this data. It was particularly noted that individuals with direct experience of the polygraph within the course of their work, in the great majority, supported the various applications of the polygraph in treating, assessing and supervising post-conviction sex offenders. Importantly, they were also more convinced of its usefulness than those who did not have any direct experience. It is notable that in Probation areas where the polygraph was being employed on a regular basis during this period, the levels of endorsement of its mandatory use for post-conviction sex offenders was even greater. This suggested that higher levels of exposure to this technology tended to equate to increased confidence in its utility.

As such, these results showed that more doubts and reservations about the use of the polygraph with sex offenders existed among professionals who did not have any direct experience of its use. The authors concluded that predisposed views about the polygraph’s use may exist influencing professionals and, perhaps people more generally. This survey provided a unique opportunity to consider factors relevant to the post-conviction introduction of the polygraph with sex offenders in a culture where the instrument is employed to a very limited degree.

In conclusion, the authors strongly endorse the necessity of conducting objective polygraph trials to examine the efficacy of this instrument in supervising, assessing and treating convicted sex offenders. Indeed, we would opine that this represents the only way to ensure any evidence-based dialogue to inform decision-making about the polygraph’s potential employment in sex offender work in the UK and, perhaps elsewhere, in Europe. Notably, the authors are aware of some current applications of the post-conviction polygraph within the Netherlands, e.g. Buschman, Wilcox, Foulger, Mulder, Sosnowski and Bogaerts (in press – 2008); Wilcox (accepted for publication – 2008).

In 2007, the Offender Management Act was passed, making provision for mandatory polygraph testing of sex offenders who are released on Licence or Parole from a custodial sentence of twelve months or more. As yet, the infrastructure for formally introducing this polygraph application to post-conviction assessment, treatment and monitoring of sex offenders has yet to be set in place but funding has now been approved. Through employment of these powers though, further study of the polygraph’s utility in this field will be welcomed by the authors and according to our study findings, by the majority of professionals working in this field.

Daniel T Wilcox and Marguerite L Donathy