Child Protection and Adult Crime: Using Investigator Assignment to Estimate Causal Effects of Foster Care

Nearly 20% of young prison inmates spent part of their youth in foster care - the placement of abused or neglected children with substitute families. Little is known whether foster care placement reduces or increases the likelihood of criminal behavior. This paper uses the placement frequency of child protection investigators as an instrument to identify causal effects of foster care placement on adult arrest, conviction, and imprisonment rates. A unique dataset that links child abuse investigation data to criminal justice data in Illinois allows a comparison of adult crime outcomes across individuals who were investigated for abuse or neglect as children. Families are effectively randomized to child protection investigators through a rotational assignment process, and child characteristics are similar across investigators. Nevertheless, investigator placement frequencies are predictive of subsequent foster care placement, and the results suggest that school-aged children who are on the margin of placement have lower adult arrest rates when they remain at home.