Polygraph testing and treatment of sexual offenders

Why polygraph testing of sexual offenders is not an effective treatment strategy

On May 9, the Colorado legislature passed House Bill 1427, which prohibits individuals with a vested economic interest in administration of polygraph tests from serving on the sex offender management board (SOMB). Beyond the issue of conflict of interest, there are other reasons to keep polygraph out of sex offender treatment decisions. The primary reasons are issues with reliability and the coercive nature of compelling disclosures about thoughts and activities (legal or illegal).

Polygraph testing in post-conviction sex offender treatment (PCSOT) is used in approximately 80% of community-based sex offender treatment programs.[1] This high rate of use continues despite the fact that in 2003 the National Research Council found little support for the accuracy of polygraph, particularly when used for screening purposes, as it is in PCSOT.[2] The lack of scientific support for polygraph testing is why the results are generally not admissible in court. Despite this lack of scientific support, some proponents of polygraph are unconcerned with the accuracy, reliability, or validity of the testing as long as it gets people to confess to deviant thoughts and “risky” behaviors.[3]

There is no objective way to measure the accuracy of the polygraph[4], but proponents claim the value is in increased disclosure of information and deterrence of offending.[5] However, claims about the value of polygraph as a deterrent to offending are not supported by research.[6] Increased disclosure of information is also not supported as having either treatment or deterrence value. In fact, a 2007 study found that there was no difference in recidivism rates between sexual offenders who were subjected to polygraph and those who were not.[7] Contrary to the purported value of increased disclosures, there is no evidence increased disclosures means decreased offending.

Decades of research regarding the use of polygraph have failed to show improvement in its reliability. Yet very little research has been dedicated to exploring whether or how polygraph improves treatment outcomes or reduces recidivism rates of sexual offenders.  Despite the known problems of reliability, and unsupported claims of efficacy in treatment and deterrence, the use of polygraph in PCSOT continues to be upheld by courts around the country as a legitimate tool in depriving individuals of their Constitutional rights and subjecting them to additional punishment.

The lack of scientific support for the use of polygraph in PCSOT should be of serious concern where individuals are at risk of being deprived of their freedom. Polygraph testing may be most effective in coercing individuals to provide socially desirable answers in an effort to be seen as scrupulously truthful. In addition, therapists who work with these offenders may be compelled to provide information to the polygraph examiner that is then used to formulate test questions. In virtually any other type of psychological treatment, this kind of coercion and sharing of information disclosed in therapy would raise significant ethical concerns. Yet in the “treatment” of sexual offenders, these questionable practices can, and do, result in further legal actions or other sanctions against the convicted offender[8], with little discussion about ethics.

The Colorado legislature rightly took steps to put an end to what appears to be a conflict of interest on the part of certain members of the SOMB. Perhaps without the influence of people who have economic interests in administering polygraph tests, the SOMB might consider whether polygraph testing is in fact an effective use of the millions of dollars it spends on this testing.[9] In terms of improving treatment outcomes and reducing recidivism, polygraph testing simply has not been demonstrated to be effective. Colorado and other states might be better advised to invest taxpayer dollars in research regarding effective treatment and management strategies, rather than continuing to fund use of a tool that does not support those goals.


[1] McGrath, R. J., Cumming, G. F., Burchard, B. L., Zeoli, S., & Ellerby, L. (2010). Current practices and emerging trends in sexual abuser management: the Safer Society 2009 North American Survey. Brandon, VT: Safer Society Press. Retrieved from http://www.deslibris.ca/ID/223961

[2] National Research Council. (2003). The Polygraph and Lie Detection. Washington, D.C.: National Academies Press. https://doi.org/10.17226/10420.

[3] Grubin, D., Madsen, L., Parsons, S., Sosnowski, D., & Warberg, B. (2004). A prospective study of the impact of polygraphy on high-risk behaviors in adult sex offenders. Sexual Abuse, 16(3), 209–222.

[4] Ben-Shakhar, G. (2008). The case against the use of polygraph examinations to monitor post-conviction sex offenders. Legal and Criminological Psychology, 13(2), 191–207. https://doi.org/10.1348/135532508X298577.

[5] Ahlmeyer, S., Heil, P., McKee, B., & English, K. (2000). The impact of polygraphy on admissions of victims and offenses in adult sexual offenders. Sexual Abuse, 12(2), 123–138.

[6] Meijer, E. H., Verschuere, B., Merckelbach, H. L. G. J., & Crombez, G. (2008). Sex offender management using the polygraph: A critical review. International Journal of Law and Psychiatry, 31(5), 423–429. https://doi.org/10.1016/j.ijlp.2008.08.007.

[7] McGrath, R. J., Cumming, G. F., Hoke, S. E., & Bonn-Miller, M. O. (2007). Outcomes in a Community Sex Offender Treatment Program: A Comparison Between Polygraphed and Matched Non-polygraphed Offenders. Sexual Abuse: A Journal of Research and Treatment, 19(4), 381–393. https://doi.org/10.1007/s11194-007-9058-z.

[8] Jensen, T. M., Shafer, K., Roby, C. Y., & Roby, J. L. (2015). Sexual history disclosure polygraph outcomes: Do juvenile and adult sex offenders differ? Journal of Interpersonal Violence, 30(6), 928–944.

[9] Osher, C. (May 14, 2017). Colorado’s pricey polygraph testing of sex offenders under fire as critics target accuracy, expense. The Denver Post. Retrieved from https://www.denverpost.com/2017/05/14/colorado-does-not-require-polygraph-testing-of-most-parolees-but-sex-offenders-get-different-treatment/.

How does data shape justice?

What we don’t know about risk assessment in the justice system

In the criminal justice system, data has become a hot topic, and often the driving force behind decisions related to law enforcement activities, pretrial release on bail, sentencing decisions, and release on parole. It is commonly believed that predictions related to recidivism that are based on algorithms and risk assessment measures will help reduce mass incarceration and the harsh collateral consequences that disproportionately impact minorities and the poor. However, this belief in the accuracy and fairness of numbers-based decision-making is based more on faith than it is on facts.

Risk assessment related to criminal recidivism is based on a variety of factors statistically correlated with criminal behavior. Some factors that are included in risk assessment tools and algorithms include age, gender, criminal history, socioeconomic status, mental illness, substance abuse, and education level, among others.

By their very nature, risk assessment tools apply group statistics to individuals. Decisions are then made about the individual (for example, whether he or she should be released on bail, or sentenced to jail/prison or probation) based on his or her shared characteristics with groups of people who have committed a new offense.

One of the primary arguments in favor of using risk assessment tools in criminal justice decisions (for example, sentencing) is that they will counteract various forms of explicit or implicit racial bias. The disparity in sentencing outcomes between whites and other minority groups is well-documented in the U.S. criminal justice system.

Much of the disparity is thought to be related to biased assumptions on the part of judges about individuals that are based on stereotypes. The question is: do risk assessment tools and algorithms overcome unfair stereotypes, or do they provide a way to make stereotypes appear objective?

Questions about the fairness and racial neutrality of risk assessment are now being raised with increasing frequency. The fact is that there is very little research that examines how risk assessment tools and algorithms impact decision-making in the justice system.

In other words – do judges actually take risk assessments into account in their decisions? Some studies indicate that risk assessment matters little to judges. Furthermore, there are serious questions about the potential for risk tools to overclassify minorities as high risk or underclassify whites as low risk that require additional study.

Finally, a question seldom considered in discussions about using risk assessment tools is how risk assessment actually impacts recidivism. A recent article in Law and Human Behavior suggests that professionals frequently fail to follow the recommendations of risk assessment tools. In addition, interventions designed to address factors that might reduce recidivism are often non-existent, or only available to a very small percentage of individuals who need them.

The authors of that study, Viljoen, Cochrane, and Johnson (2018) conclude that the use of risk assessment tools does not automatically translate into effective treatment or risk management. Identifying offender needs without addressing those needs may simply result in individuals assessed as “high risk” being subject to additional punishment.

Conclusions about the impact of risk assessment on criminal justice decision-making are premature, as are conclusions about whether risk assessment tools and algorithms have a disproportionately negative impact on minorities and the poor. In addition, the assessment of risk does not guarantee interventions matched to risk reduction, and can mean more punishment for some.

Very little research has been done on these questions of primary importance, suggesting that widespread implementation of these tools is ill-advised without considering the real consequences rather than what we hope will happen.

Why a good defense and the justice system need science

By Jennifer Kamorowski

February 25, 2018

In May of 2016, I started my business, Strategic Sentencing Solutions, LLC. The idea behind this company is that attorneys, their clients, and the courts can benefit from scientific research. Attorneys are experts at making persuasive legal arguments to help their clients; they do the legal research and know the most recent and relevant case law to argue their client’s case. However, because attorneys are frequently overworked and pulled in many different directions, they probably don’t have time to stay knowledgeable and informed about social science research. In addition, the courts and judges rely on attorneys and experts to present the best evidence available to inform judges’ decisions. Many cases might not rise to the level of requiring an expert witness, or the funding simply may not be there to cover that expense. That’s where my business can help – because I help situate the unique circumstances and characteristics of the individual client in the context of the scientific research in psychology and other social science fields.

So how does this help? Here are the three primary ways: 1) assists attorneys with research they are often too busy to do themselves; 2) particularly targeted to clients charged with a crime who must defend themselves with limited public or personal funds; and 3) provides empirical research upon which decision-makers can make more informed choices regarding case dispositions. I addressed the first issue in the opening to this post, so I will say a bit more about the other two factors.

It is estimated that 80% of people charged with a felony are indigent (Mosteller, 2011, p. 326). That means the accused cannot afford to hire his or her own attorney and must rely on a public defender to argue his or her case. In 2007, the U.S. Department of Justice estimated that 73% of county public defenders carried caseloads that exceeded the maximum recommended by the National Advisory Commission on Criminal Justice Standards and Goals (1973). Some would even argue those recommendations are set too high and are unrealistic given the realities of today’s criminal justice system (Texas A&M University Public Policy Research Institute, 2015). These numbers set out the huge proportion of criminal defendants who are unable to afford private representation and the tremendous burden on the public defenders who are assigned to represent them. Funding is usually very limited, and not every case reaches the level of requiring an expert witness to testify. My goal is to address both of these issues by providing the most current scientific research to support defense legal arguments at a substantial cost savings, while also seeking to achieve better-informed justice outcomes. This leads me to my final point about the use of empirical scientific research informing case dispositions.

In about 95% of criminal cases, the case ends in a plea deal (Perez, 2011). However, leading up to that point, there are negotiations with the prosecuting attorney about sentencing options. Whether a client pleads guilty or is convicted at trial, there is the issue of convincing the government and the judge and/or jury about the viability and wisdom of proposed recommendations. Within these negotiations and decision-making, there exists an opportunity to leverage existing social science research to improve the recommendations and outcomes for defendants. This type of research can help situate the individual, based on his or her unique circumstances and characteristics, within the broader context of what is known about similarly-situated groups of people. The same can be said in the case of resentencing. For example, it may be important to identify what existing scientific research says about adjustment in prison to successfully argue for a reduction of a death sentence to life in prison without parole. In cases of lesser sentences, it’s important to identify what existing research says about the success of particular rehabilitation programs and their impact on recidivism. These are but two examples of ways in which the research happening in fields of social science can ultimately improve outcomes for individual clients while also advancing goals of public safety and reduction of recidivism.

In my past experience working with exceptional defense attorneys, mitigation specialists, social workers, and sentencing advocates, I have seen the tremendous empathy and dedication they bring to client advocacy. I have listened to stories about clients that are filled with heartbreak, but also with hope and change. I ultimately wanted to find a way I could support these advocates, their clients, and the community. The answer I came up with is to help bridge the gap between the law and science in a way that can advance the humanity in justice. Utilizing empirical research to improve individual outcomes and increase public safety? I think that is a win-win strategy.


Farole, Jr., D. J., Langton, L. (2010). County-based and Local Public Defender Offices, 2007 (NCJ 231175). Washington, DC: U.S. Department of Justice.

Mosteller, R. P. (2011). Failures of the American adversarial system to protect the innocent and conceptual advantages in the inquisitorial design for investigative fairness. North Carolina Journal of International Law & Commercial Regulation, XXXVI, 319-363.

Perez, D. A. (2011). Deal or no deal? Remedying ineffective assistance of counsel during plea bargaining. The Yale Law Journal, 120, 1532-1577.

Texas A&M University Public Policy Research Institute. (2015). Guidelines for Indigent Defense Caseloads: A Report to the Texas Indigent Defense Commission. College Station, TX: Public Policy Research Institute.