Gregory Stewart

  • Inducted June 2017
  • Nominated by Kris Henning, Portland State University (with support from Tim Hegarty, Riley County (KS) Police Department, and Gary Cordner).



Sergeant Greg Stewart has spent over 21-years with the Portland Police Bureau (PPB). During his tenure, he has worked in patrol, investigations, and the PPB’s centralized crime analysis unit. In 2009, Stewart was transferred to PPB’s Strategic Services Division to build its new Crime Analysis Unit. The unit now provides both crime analysis and assistance in research and planning. Stewart holds a Masters of Science in Criminology and Criminal Justice from Portland State University and a B.A. in Psychology from Lewis and Clark College. He is a founding member of the American Society of Evidence-Based Policing and a National Institute of Justice LEADS Scholar.


Evidence-Based Research and Practice:

Sgt. Stewart was first introduced to evidence-based practices in 2007 when collaborating with Professor Kris Henning of Portland State University who developed an automated actuarial risk assessment system for PPB’s Domestic Violence Reduction Unit (DVRU). This system provided over 6,000 risk assessments annually and was used in conjunction with a domestic violence report developed using evidence-based practices to aid in case assignment. Later, Stewart spearheaded another project within the DVRU that involved revising the Bureau’s Family Abuse Supplemental Form. Prof. Henning noted that Stewart’s ability to communicate with diverse groups and gain buy-in from multiple players helped to change the form, allowing case decisions to be more victim centered, and facilitating risk assessment further.

After transferring to PPB’s Strategic Services division, Stewart played a significant role in launching a new crime analysis unit. Professor Henning writes that the unit is “one of the best Crime Analysis units in the country. The scope of work being done in the unit far exceeds traditional data analysis and mapping: they are driving the Bureau’s movement toward evidence-based practice. This includes extensive collaborations with academic partners.” Stewart collaborated with Portland State University on a 2014 Smart Policing Initiative with the Bureau of Justice Assistance, which included conducting a large randomized field experiment on hot spots policing. The project examined the impact of patrol dosage and community engagement on calls for service, crime, and community attitudes. Other research projects that Stewart has worked on include public attitudes toward the police, police use of force, police communications, and police interactions with people suffering from mental illness. He has also been a part of an innovative trial with the Bureau of Emergency Communications in developing a system for uploading directed patrol calls into dispatch systems so to dispatch officers proactively for purposes of crime prevention and community outreach.

Prof Henning notes that Stewart “is one of those rare individuals who stays curious, keeps asking the important questions, and is always willing to investigate what can be learned about the practice of law enforcement using social science methods.” Cpt. Tim Hegarty, of the Riley County (KS) Police Department adds that “While Greg clearly understood the science behind evidence-based policing research, he also understood that without the ability to translate the research into practice, the science was meaningless.”

Stewart currently is a Law Enforcement Advancing Data Science (LEADS) Scholar with the National Institute of Justice, a Policing Fellow with the Police Foundation and a founding member of the American Society for Evidence-Based Policing.


Statement from Sgt. Stewart:




Kahn, K.B., Lee, J.K, Renauer B., Henning K. & Stewart, G. (2016). The effects of perceived phenotypic racial stereotypicality and social identity threat on racial minorities’ attitudes about police, The Journal of Social Psychology, DOI: 10.1080/00224545.2016.1215967.

Kahn, K. B., Steele., J., McMahon, J.M., & Stewart, G. (2016). How suspect race affects police use of force in an interaction over time. Law and Human Behavior. No Pagination Specified (online). DOI: 10.1037/lhb0000218.

Stewart, Greg, Kris Henning, and Brian Renauer. Public Perceptions Regarding the Use of Force by Police in Portland, Oregon. Issue brief. N.p.: Criminal Justice Policy Research Institute (CJPRI), 2012.

Stewart, G. (2013). A quantitative method for the analysis of constitutional factors in police use of force (Unpublished master’s thesis). Portland State University, Portland, OR.

Stewart, G., Gerritsen, L., Covelli, E., & Henning, K. (2011). Report on Police Interactions with Person in a Mental Health Crisis. N.p., Portland Police Bureau.