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Abstract Submission - IATSO 2025


Working with individuals who deny responsibility for offending sexually

Liam E. Marshall


While most individuals convicted of a sexual crime make excuses for their behavior through omitting or underplaying certain aspects or its consequences, a small number of these individuals will steadfastly continue to deny responsibility. These individuals maintain that they are innocent and have been wrongly accused or convicted and are often released to the community not having participated in treatment. These individuals pose assessment, management, and treatment challenges. Clinicians often describe significant difficulties engaging and working with these individuals. Practitioners also appear to have polarized views about this group of offenders, most notably in terms of whether or not denial equates to an increased risk of recidivism, if deniers can be treated, or even if they should receive treatment at all. 

This preconference workshop will present a review of the literature on what is known about deniers and present new data about the function of categorical denial. Then, the methods and effectiveness of a range of treatment approaches to overcoming denial will be described. Finally, the description and effectiveness of an approach where denial of having sexually offended is not challenged and instead focuses on empirically identified criminogenic issues will be presented. Workshop participants will be provided a rational for this treatment approach as well as practical assessment, risk assessment, and treatment guidance. This will include use of case studies and examples.


Selected Abstract References (omitted from text): 

Marshall, W. L., Thornton, D., Marshall, L. E., Fernandez, Y. M., & Mann, R. E. 

(2001). Treatment of men with sexual convictions who are in categorical denial: A pilot project. Sexual Abuse: A Journal of Research and Treatment, 14, 205-215..

Ware, J., Blagden, N., & Harper, C. (2018). Are categorical deniers different? 

Understanding demographic, personality, and psychological differences between denying and admitting individuals with sexual convictions. Deviant Behavior, 29, 1-4.

Ware, J., Marshall, W. L., & Marshall, L. E. (2015). Categorical denial in convicted 

men with sexual convictions: The concept, its meaning, and its implication for risk and treatment. Aggression and Violent Behavior, 25, 215-216.


Liam Marshall, Ph.D., RP, ATSAF received his Doctoral and other degrees in Psychology from Queen’s University in Kingston, Canada. He has been providing treatment and conducting research on offenders and offenders with mental health issues for more than 25 years. Liam has more than 100 peer- reviewed publications and is co-author/co-editor of four books. He is a board member and reviewer for many international journals, and has made numerous international conference presentations on offender and mental health issues. He has provided consultation to governments and delivered trainings for therapists and staff working with offenders in 28 countries. Liam has been named a Fellow of the Association for the Treatment of Sexual Abusers (ATSA). He is currently Director of Rockwood Psychotherapy & Consulting and an Assistant Professor in the Department of Forensic Psychiatry at the University of Toronto. 

Dr Jayson Ware, Ph.D. is currently Senior Lecturer in Criminal Justice, Faculty of Law, University of Canterbury, New Zealand. He was previously Group Director, Offender Services and Programs, Corrective Services New South Wales, Australia. He has worked with sexual offenders for the past twenty years and has authored over 40 journal articles or book chapters primarily relating to the treatment of sexual offenders. He completed his early clinical psychology studies at the University of Canterbury, New Zealand before completing his Ph.D. at the University of New South Wales, Australia. He has a particular research interest in sex offender denial.