Can Criminal Symbiosis Explain the Persistence of Violence in Brazil?

This paper develops the concept of “criminal symbiosis” to explain the persistence of violence in Brazil. Using official historical series, we document a systematic co-movement between serious crimes and minor offenses, suggesting a process of mutual reinforcement. When minor crimes increase, policing costs rise and the expected punishment for severe offenses declines, enabling escalation into homicide and organized crime. Conversely, targeted repression of minor infractions helps restore social norms and generates measurable deterrent effects. We formalize this mechanism through a dynamic system linking offender stocks, institutional responses, and intergenerational transmission of crime. The framework provides clear testable implications and supports integrated crime-prevention strategies that combine enforcement, rehabilitation, and community resilience.