KIRAT: Law Enforcement’s Prioritization Tool for Investigating Indecent Image Offenders Matthew Long Kent Police, Maidstone, United Kingdom Laurence Alison and Ricardo Tejeiro University of Liverpool Emma Hendricks Kent Police, Maidstone, United Kingdom Susan Giles University of Liverpool The proliferation of indecent images of children (IIOCs) on the Internet has exceeded the resources required to investigate suspects effectively. This article examines the validity of the Kent Internet Risk Assessment Tool—Version 2 (KIRAT– 2), an evidence-based framework for prioritizing IIOC suspects according to their risk of committing contact offenses against children. Data were obtained from 374 police files (11 police forces across the United Kingdom) corresponding to individuals who were convicted for IIOC offense(s) during the period 2001–2013. Some 170 offenders had convictions or allegations of contact sexual offenses against children; police defined these as higher risk of contact offending (HR) as opposed to the remaining 204 individuals without convictions or allegations of contact sexual offenses (lower risk of contact offending, LR). We coded 166 variables previously discussed in the literature or from law enforcement experience that may discriminate dual from noncontact offenders. Receiver operating characteristic (ROC) curve analysis was conducted to test which variables or combination of variables discriminated between HR and LR offenders. The final model, represented as a phased decision tree, uses 17 variables with 4 filters or decision steps examining previous convictions, access to children, current evidence of both online and offline behavior, and other relevant factors. The model classified 97.6% of HR within the higher risk levels (high or very high) and 62.3% of LR within the lower risk levels (low or medium). Findings are discussed in terms of contribution to the Internet sex offending risk assessment literature and practical implications for police forces. Keywords: child pornography, child sexual abuse, Internet, indecent images of children, risk assessment Supplemental materials: http://dx.doi.org/10.1037/law0000069.supp The increasing use of the Internet and technological advance- ments has contributed to a proliferation of indecent images of children (IIOCs) on the World Wide Web and hidden Internet. There are estimated to be more than one million IIOCs on the Internet at any one time, with 200 new images posted daily (Wellard, 2001). The number of IIOC offenders connected to the Internet at any one time is estimated to be around 750,000 (Maalla, 2009). In recent years, the growing number of IIOC cases has created a growing workload for the police forces dealing with them (Elliott, Beech, Mandeville-Norden, & Hayes, 2009). The scale of the offending problem in the United Kingdom (U.K.) has been outlined by the Child Exploitation and Online Protection Centre (CEOP). CEOP estimated that during 2012 there were around 50,000 individuals involved in downloading and Matthew Long, Child Exploitation Investigation Team, Kent Police, Maidstone, United Kingdom; Laurence Alison and Ricardo Tejeiro, Department of Psychological Sciences, University of Liverpool; Emma Hendricks, Child Exploitation Investigation Team, Kent Police; Susan Giles, Department of Psychological Sciences, University of Liver- pool. This article is part of the Fighting International Internet Paedophilia (FIIP) project, participated in by police agencies and universities from several European countries—Kent Police and University of Liverpool (United Kingdom), Mossos d’Esquadra and Universitat de Barcelona (Spain), Politie Rotterdam Rijnmond (The Netherlands), Politsei ja Piirivalveamet (Estonia), University College Dublin (Ireland)—and jointly funded by the European Commission. The authors declare no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. We thank the following persons for their assistance with this project: Anthony Beech, Chris Hogben, Charlotte McCallum, Grace McGuire, Michelle McManus, Jane Oyston, Manuel Pelegrina, Ethel Quayle, Hayley Rhodes, Zoe Scotton-Pinhey, Neil Shortland, Sarah Smith, and Clair Tucker. Also, we want to express our gratitude to the Child Exploitation Investigation Team (CEIT) at Kent Police, with particular thanks to David Holmes, David Shipley, and Ellie Caws, as well as to the United Kingdom Police Forces that provided cases for the academic studies, specifically Avon & Somerset, Devon & Cornwall, Dorset, Essex, Hampshire, Hert- fordshire, Kent, Merseyside, Metropolitan Police Service, Norfolk, Suf- folk, Surrey, Sussex, West Midlands, and Wiltshire. Correspondence concerning this article should be addressed to Laurence Alison, Department of Psychological Sciences, University of Liverpool, Elea- nor Rathbone Building, L69 7ZA, Liverpool, United Kingdom. E-mail: l.j.alison@liverpool.ac.uk This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. Psychology, Public Policy, and Law © 2016 American Psychological Association 2016, Vol. 22, No. 1, 12–21 1076-8971/16/$12.00 http://dx.doi.org/10.1037/law0000069 12