Our Troubling Failures in Catching Criminals: Rethinking Legal Limits on Crime Investigation

Justice is failing in America. Clearance rates – the rate at which police identify a crime’s perpetrator – are tragically low for most crimes, even serious offenses. In 2020, there were 24,576 homicides in the U.S. and police solved just 10,115 of those, for a clearance rate of 41%. Yet murder has by far the highest clearance rate for serious offenses. The clearance rate for aggravated assault is 7% and for rape is 2.5%. Even more problematic is the fact that clearance rates are falling. The data suggest that the national homicide clearance rate dropped by 22% between 1980 and 2020. Indeed, the clearance rate for most offenses has dropped over the last several decades. This downward trend is all the more troubling because it comes despite dramatic technical advances in our ability to solve crimes, as in the increasing availability and sophistication of DNA crime scene analysis. It is also troubling because the decrease in clearance rates is occurring despite the fact that many jurisdictions have broadened their definition of what counts as a “cleared case.” To make things still worse, it is now clear that clearance rates are significantly lower for crimes in which the victim is Black. Indeed, almost all of the recent nationwide decline in homicide clearance rates comes from unsolved killings of Black victims. The clearance rate problem is seriously consequential. First, failing to identify a perpetrator necessarily means a failure of justice where a blameworthy offender escapes deserved punishment. But low and decreasing clearance rates also have worrying practical consequences. It lets dangerous offenders go free to victimize others. But perhaps of greater long-term significance, the tragically low clearance rates damage the criminal law’s moral credibility with the community, which in turn tends to increase community resistance, subversion, and vigilantism. Further, low and decreasing clearance rates undermine the general deterrent effect of the criminal justice system, which is likely to produce more crime, which in turn commonly produces lower clearance rates, and so on, creating a tragic downward spiral. An improvement in clearance rates would not only break that vicious cycle but also present an opportunity to reduce lengthy incarceration, which has its own societal costs. The criminal justice system’s general deterrent threat is a function of the seriousness of the punishment threatened times the likelihood of that punishment being imposed. To the extent that the latter (likelihood) can be increased by improving clearance rates, the former (amount) can be reduced, allowing less incarceration while maintaining the same overall deterrent threat. What can be done to improve our performance in solving crimes? A greater investment in investigative resources (such as laboratories), more detectives, and better training of investigators would all help. But the question for legal policymakers is what changes in law are likely to improve the rate of solving serious crimes? That is the subject of this article. When one considers the enormous societal costs of low clearance rates, a proper balance of the competing societal interests suggests a change in the current legal rules governing criminal investigation.