Lars Madsen

Lars Madsen conducted his polygraph research while affiliated with the Department of Psychiatry at the University of Newcastle-upon-Tyne in the United Kingdom, working closely with Don Grubin during the early-to-mid 2000s. He is currently the Clinical Director of the Forensic + Clinical Psychology Centre in Australia, where he works as both a clinical and forensic psychologist across clinical, community and custodial settings. Madsen is a Fellow of the APS College of Clinical Psychologists and holds a Ph.D. from the University of Newcastle-upon-Tyne.

Madsen made significant contributions to the emerging field of post-conviction sex offender polygraph testing (PCSOT) during his active research years. His 2004 preliminary study concluded that polygraph testing had an impact on the level of seriousness of risk behaviours engaged in by sex offenders, though this only occurred after experience of the test itself. His landmark 2006 study with Grubin found that based on self-report, the polygraph's accuracy was approximately 85%, supporting the view that the polygraph is both accurate and useful in the treatment and supervision of sex offenders. His 2005 historical review article traced the development of polygraphy from its emergence in the United States to newer applications in sex offender treatment and supervision.

Madsen's work was influential enough that he served as co-editor (alongside Don Grubin and Daniel Wilcox) of the practitioner's guide "The Use of the Polygraph in Assessing, Treating and Supervising Sex Offenders," a key reference work in the field. His collaboration with Grubin and Parsons at Newcastle produced some of the most cited empirical evidence for PCSOT implementation. His research profile shows he has been cited over 1,500 times, indicating substantial impact on subsequent polygraph research and sex offender management practices.

Since relocating to Australia, Madsen has trained as a schema therapist and is passionate about developing forensic schema mode therapy as a method of engagement with offenders who have chronic and enduring difficulties. He is now an advanced accredited schema therapist, supervisor, and trainer recognized by the International Society of Schema Therapy (ISST), with a passion for working with personality disorders and complex trauma. His polygraph work during 2004–2006 represents a focused period of empirical research that helped establish the scientific foundation for post-conviction polygraph use in the UK and internationally.