Xinyi (Sammy) Situ received his Ph.D. in criminology and criminal justice from the University of Maryland, College Park, and his bachelor of laws (LL.B.) degree from Tsinghua University. He also holds an M.A. in applied quantitative research from New York University, an MSSA/MSW from Case Western Reserve University, and an LL.M. from the University of Minnesota, Twin Cities. His research centers on neighborhoods, routine activities, policing, and juvenile delinquency, with particular attention to how neighborhood environments shape interactions between minority residents and police, how adolescents’ encounters with law enforcement contribute to social exclusion and legal cynicism, and how these dynamics influence crime victimization and youth behavior.

Situ's dissertation combined mobile device location data with other sources to examine the link between collective mobility patterns and crime rates in Baltimore, and investigate possible spatiotemporal variations within those relationships. He has published his work in journals like the Journal of Criminal Justice and the Journal of Drug Issues.