Crime & Policy

Crime, criminology, and public policy.

Do Mandatory Minimum Sentences Deter Crime? What the Evidence Shows

nonacademicresearch.org Editorial · May 9, 2026 · submitted by nonacademicresearch.org Editorial · nar:008rvacdoy8eei3o9z

Mandatory minimum sentencing laws — which require judges to impose fixed minimum prison terms for specified offenses — became widespread in the United States beginning in the 1980s, primarily targeting drug offenses and violent crimes. Proponents argued that certainty and length of punishment would deter crime and incapacitate repeat offenders. The empirical evidence accumulated over four decades finds that mandatory minimums have limited deterrent effects and impose substantial social costs, with a growing consensus among economists and criminologists that sentence length is a weak tool for reducing crime compared with increasing the certainty of punishment.

Do More Police Reduce Crime? Evidence From Natural Experiments

nonacademicresearch.org Editorial · May 9, 2026 · submitted by nonacademicresearch.org Editorial · nar:o1bx9rbyswe0y4hwbh

One of the central debates in criminal justice policy concerns whether increasing the number of police officers and patrol presence reduces crime. Observational studies are confounded by the fact that high-crime areas tend to have more police. Natural experiments — events that changed police presence for reasons unrelated to crime — have allowed economists and criminologists to identify causal effects. The evidence consistently finds that more police reduce violent crime, though the mechanisms and magnitude remain debated.

Does Incarceration Reduce Recidivism? What the Evidence Shows

nonacademicresearch.org Editorial · May 9, 2026 · submitted by nonacademicresearch.org Editorial · nar:i4b9ymbt5gjjv15zmm

The United States incarcerates approximately 2 million people — more than any other country in absolute terms and among the highest rates per capita globally. The central justification for incarceration beyond punishment is that it reduces future crime, either by deterring would-be offenders or by incapacitating people who would otherwise reoffend. The empirical evidence on recidivism — reoffending after release — does not support the view that current incarceration practices reduce reoffending. Longer sentences do not produce lower reoffense rates, and some evidence suggests incarceration increases recidivism risk relative to community-based alternatives.

Lead Exposure and Violent Crime: The Evidence for a Causal Link

nonacademicresearch.org Editorial · May 9, 2026 · submitted by nonacademicresearch.org Editorial · nar:rnp400nf66z7cav9u2

The correlation between childhood lead exposure and subsequent violent crime rates is one of the most replicated findings in environmental criminology. Causal evidence — from natural experiments around leaded gasoline phase-outs, housing remediation programs, and industrial accidents — consistently shows that reducing lead exposure reduces violent crime, with effect sizes large enough to explain a substantial fraction of the crime rise and fall in the United States from the 1960s through the 1990s.