David Schaefer earned his Ph.D. in Sociology from the University of Arizona in 2006, his M.A. in Sociology from Washington State University in 1998, and his B.A. in Sociology from the University of Tulsa in 1994. Prior to his doctoral studies, he served as Faculty Research Associate in the Administration of Justice Department at Arizona State University West from 1998 to 2001, where he led a project gathering drug use data from arrestees in local jails in Phoenix, Arizona. Following his Ph.D., Schaefer joined Arizona State University as Assistant Professor in the School of Social and Family Dynamics from 2006 to 2012, then advanced to Associate Professor in the School of Human Evolution and Social Change from 2012 to 2017. His research specializations include social networks, social psychology, group processes, criminology, health, and human development. Schaefer has investigated peer influence on behaviors such as smoking initiation and cessation, network selection mechanisms underlying depression homophily, the role of neighborhood context in youth co-offending, and social dynamics within prison populations.

Schaefer's contributions earned him the 2012 Freeman Award for Distinguished Scholarship from the International Network for Social Network Analysis. He co-led an NSF-funded Prison Inmate Networks Study with collaborators from Arizona State University's School of Criminology and Criminal Justice. Key publications include 'Misery Does Not Love Company: Network Selection Mechanisms and Depression Homophily' (American Journal of Sociology, 2011), 'With a Little Help from My Friends? Asymmetrical Social Influence on Adolescent Smoking Initiation and Cessation' (Journal of Health and Social Behavior, 2014), 'The Contribution of Extracurricular Activities to Adolescent Friendships' (Journal of Research on Adolescence, 2011, with Sandra D. Simpkins, Andrea E. Vest, and Chara D. Price), 'New on the Block: Analyzing Network Selection Trajectories in a Prison Treatment Program' (American Sociological Review, 2020, with Derek A. Kreager), and 'Network Integration within a Prison-Based Therapeutic Community' (Social Networks, 2021, with Kimberly M. Davidson, Dana L. Haynie, and Martin Bouchard). At Arizona State University, he served on graduate studies committees, chaired social networks search committees, organized the 25th Annual Group Processes Conference in 2012 and an Advanced SIENA User’s Meeting, coordinated the Cluster for the Advancement of Social Network Analysis, and held editorial roles including on the board of Connections from 2012 to 2021.