Examining the Predictive Validity of the Static-99R on Native American Sex Offenders

Abstract

No study to date has evaluated the predictive validity of the Static-99R on a sample of Native American sex offenders. This study provides such an investigation. Findings reveal the Static-99R demonstrates small predictive validity for new sexual recidivism charges (AUC = 0.599) at five years for all offenders. However, the predictive validity for the sample of Native American sex offenders reaches moderate predictive validity (AUC = 0.672) when examined separately. Additional metrics beyond area under the curve analyses are used to assess the three dimensions of predictive validity: accuracy, discrimination, and calibration. Implications of the findings are discussed.

Keywords:

• Sex offender
• risk assessment
• predictive validity
• Static-99R
• Native American offenders

Disclosure statement

No potential conflict of interest was reported by the author.

Notes on contributor

Andrew J. Myer, Ph.D., is an Assistant Professor in the Department of Criminal Justice and Political Science at North Dakota State University. His research interests include: Evidence-based correctional practices, program evaluation, and time-series analysis.

Notes

1 The Static-99R is a revised version of the Static-99. The difference between the two instruments is the operationalization of age of the offender. The Static-99R expanding the number and weighted scoring of age construct, adding points for younger offenders, and subtracting points from older offenders (Helmus, Thornton, et al., 2012). There is also an additional version of the tool known as the Static-2002/R; however, the Static-99R remains more widely used and more researched (see Reeves, Ogloff, & Simmons, 2018).

2 New risk categories were published in 2016 (see Phenix et al., 2016) that created five categories instead of four. The scoring done by the state correctional department occurred prior to 2016, so all scoring was done using the previous four category standards.

3 The following offenses were included as sex crimes: Gross sexual imposition, sexual imposition, continuous sexual abuse of a child, corruption of a minor, sexual assault, sexual exploitation by therapist, sexual abuse of wards, deviant sexual acts, incest, solicitation of a minor, luring by computer, indecent exposure, position, manufacturing, distributing, or producing child pornography, and surreptitious intrusion.