Most gun violence in the United States goes unsolved. In a new essay for the Harry Frank Guggenheim Foundation, renowned crime scholar Phil Cook explores some emerging strategies to change that.
In 2024, an estimated 75,000 people were shot by criminal assailants, and nearly 15,000 of those victims died. The majority of these shootings did not result in an arrest or conviction. This failure leaves victims and survivors without justice, allows shooters to remain at large, and undermines public confidence in the criminal justice system. Because gun violence is heavily concentrated in low-income Black communities, low investigative success rates are not only a public safety concern but also a racial equity issue.
Effective investigation of serious violence serves two core goals. First, it provides justice and closure for victims and survivors. Second, it contributes to crime reduction. Solving shootings incapacitates repeat violent offenders, triggers legal firearm prohibitions for convicted felons, deters some would-be offenders when punishment is credible, and reduces the likelihood of retaliatory violence. Although policy debates about gun violence often emphasize prevention through regulation or social services, these approaches cannot substitute for the crime control and justice functions of effective police investigations.
Police performance in this domain is typically measured using clearance rates, usually defined by the FBI as cases cleared by arrest or by exceptional means. While clearance rates provide a useful signal, they are an imperfect proxy for success. Many arrests do not result in prosecution or conviction, especially in nonfatal shooting cases. Clearance rates also vary with case mix, investigative difficulty, and local standards for arrest, which makes comparisons across cities and over time misleading if taken at face value. Clearance rates should therefore be interpreted cautiously, but they remain one of the few available indicators of investigative effectiveness.
Despite measurement challenges, there is strong evidence that police departments can improve investigative outcomes through targeted investments and organizational reforms. One of the most important levers is reducing detective caseloads for serious violent crimes. When investigators have sufficient time and support per case, clearance rates increase. Experience from cities, such as Boston’s Homicide Clearance Project, shows that increased staffing, stronger supervision, standardized investigative practices, and focused training can raise clearance rates even for gang and drug related homicides.
A particularly promising and underused strategy is to give nonfatal shootings investigative priority comparable to homicides. Fatal and nonfatal shootings are similar in circumstances, offender risk, and prevention payoff. Whether a victim lives or dies is often a matter of chance rather than intent. Yet nonfatal shootings are far less likely to be solved, largely because they are assigned fewer resources and are investigated by detectives with heavier caseloads. Denver’s Firearm Assault Shoot Team (FAST) program, which assigned homicide-level resources to nonfatal shootings, produced immediate increases in arrest rates. Solving nonfatal shootings is likely to prevent future violence at a scale comparable to solving homicides.
Another critical constraint on investigative success is victim and witness cooperation. Surviving shooting victims often distrust police, fear retaliation, or adhere to no-snitching norms. When victims refuse to cooperate, cases are frequently unprosecutable. Evidence from Indianapolis Metropolitan Police’s Non-Fatal Shooting and Advocacy Support Program suggests that proactive victim support, including dedicated victim services staff and credible protections against retaliation, can increase cooperation and improve case outcomes. Indianapolis provides a leading example of how structured victim outreach can enhance investigative effectiveness.
Technology can also support investigations, but it is not a substitute for staffing and organizational capacity. Tools such as video evidence, digital forensics, ballistics, and DNA are most effective when centralized, professionally staffed, and integrated into investigative workflows. Chicago’s Area Technology Centers (ATCs), which provide specialized support to detectives handling shootings with video or digital evidence, coincided with improvements in the rate of homicide cases that were prosecuted, even during periods when citywide violence surged. Chicago’s example suggests that
Current clearance and conviction rates for shootings fall well short of reasonable expectations. Improving investigative outcomes will require sustained investment in detective staffing, management, victim engagement, and selective technological support, along with continued evaluation to identify cost effective practices. While prevention efforts remain essential, violence is far harder to reduce and justice far harder to deliver when serious violent crimes are unlikely to result in arrest and conviction.
Read the full essay here.
