Prisons do not make us safer. They are ineffective at reducing crime; they are costly; they have negative effects that far outweigh any utility (read more in our issue brief here). Overall, the best research finds:

  • There is no clear link between incarceration rates and crime rates globally. Countries with higher incarceration rates do not have lower crime rates. In most countries of the global North crime rates have dropped dramatically since the 1990’s, while other regions like Latin America have seen increases. Yet incarceration rates have continued to increase independent of crime rates.
  • National studies find minimal impact of incarceration on crime with diminishing returns. Studies have found that even in instances where incarceration rates have a small impact on crime rates, almost all (75-100%) of that variation in crime rates is explained by other factors. Also, each additional increase in incarceration rates has a smaller impact on crime rates than previous increases.
  • There is no evidence that incarceration reduces violent crime. The minimal crime reduction attributed to incarceration is limited to property crime; higher incarceration rates have not been shown to have any impact at all on violent crime rates.
  • Harsher punishment does not deter crime. Studies that empirically test the assumption that more severe punishment is more effective in keeping people from committing crimes find no deterrent effects sufficiently large to justify the social and economic costs of incarceration.
  • “Incapacitation” may slightly reduce some crime, but not enough to outweigh the negative aftereffects. Taking some people who commit the crime out of society—incapacitation—can reduce some crime in the short-term. But the time spent in prison also increases the likelihood of a person committing more crime after prison, and has devastating effects on incarcerated people, their families, and communities. In summary, the negative effects of incarceration outweigh any societal benefit from temporary incapacitation.
  • Incarceration can increase crime communities. Concentrated incarceration in certain communities can erode protective factors that guide people away from crime (i.e. strong family and social relationships and economic opportunity) and lead to increased crime in neighborhoods.
  • The costs of incarceration are high. There is wide variation between countries, but prison budgets average 0.3% of GDP. This cost can be up to three times higher if considering other direct costs such as fees and costs to families. Most estimates, however, don’t come close to covering the indirect health, economic and social costs of incarceration – including the intergenerational perpetuation of an already systemic poverty.
  • Non-prison-based responses to crime are more effective and cost less. Evidence shows that people given non-custodial sentences have no higher, if not lower, likelihood of recidivism than those given custodial sentences. There is strong evidence of the effectiveness of alternative-to-incarceration programs that successfully reduce recidivism. Non-custodial programs are far more cost effective and avoid the negative impacts of incarceration.
  • It is possible to reduce BOTH incarceration and crime. Some noteworthy examples of countries and states that have done so include Finland, Alberta (CA), New York, New Jersey and California (USA).