In 1999, on Super Bowl Sunday, two-year-old Miguel Arias-Baca lay dying on the bathroom floor of his Denver, Colorado, foster home. His foster father, upset that Miguel had soiled his diaper, smeared the boy’s face in his own feces and threw him to the ground. Miguel’s brain swelled with blood, but his foster parents waited more than four hours before they took him to the hospital. The child, covered in bruises, died.

As news of this tragic incident spread, people began to ask how such a thing could happen. After all, foster parents were supposed to be dedicated to caring for the children entrusted to their care. Indeed, foster care can provide a welcome refuge for children of abusive parents. However, critics of child protection programs argue that recent trends in child abuse policies promote foster care at...