Her primary research interests include police-citizen relations, cross-national research on crime and delinquency, law enforcement responses to prescription opioid abuse, and the applications of quantitative methods. Dr. Ren was part of the research team that conducted the 3-waves of citizen satisfaction surveys funded by the Houston Police Department between 2010 and 2014. She has worked with various criminal justice agencies providing research assistance and evaluations. Her recent research endeavor, in collaboration with the Montgomery County District Attorney's Office, involves formulating and assessing law enforcement responses to prescription opioid abuse. Her scholarship has appeared in a variety of refereed journals, including Justice Quarterly, Crime & Delinquency, Journal of Criminal Justice, Journal of Research in Crime & Delinquency, and Police Quarterly.