Neighborhood variation in unsolved homicides: a retrospective cohort study in Indianapolis, Indiana, 2007–2017

Background Homicide is a widely acknowledged public health problem in the United States. The majority of homicides are committed with a firearm and have long-term health consequences for family members and entire communities. When left unsolved, violence may be perpetuated due to the retaliatory nature of homicides. Improving homicide clearance rates may help prevent future violence, however, we know little about the community-level social dynamics associated with unsolved homicides. Methods This study examines the individual-and-community-level social processes associated with low homicide clearance rates in Indianapolis, Indiana between 2007 and 2017. Homicide clearance is the primary outcome, defined as if a perpetrator was arrested for that homicide case between 2007 and 2017. Individual-level variables include the victim’s race/ethnicity, sex, and age. Community-level (i.e., census tracts) variables include the number of resident complaints against the police, resident complains of community disorder, income inequality, number of police interactions, and proportion of African American residents. Results In Indianapolis over a 11-year period, the homicide clearance rate decreased to a low of 38% in 2017, compared to a national clearance rate of 60%. Homicide case clearance was less likely for minority (OR 0.566; 95% CI, 0.407–0.787; p < 0.01) and male (OR 0.576; 95% CI, 0.411–0.807; p < 0.01) victims. Resident complaints of community disorder were associated with a decreased odds of case clearance (OR 0.687; 95% CI, 0.485–0.973; p < .01)., African American victim’s cases were less likely to be cleared in 2014–2017 (OR 0.640; 95% CI, 0.437–0.938; p < 0.05), compared to 2007. Conclusions Our study identified differences in neighborhood social processes associated with homicide clearance, indicating existing measures on these community factors are complex. Programs aimed at improving signs of community disorder and building community engagement may improve neighborhood clearance rates, lower violence, and improve the health of these communities.

Reconsidering Homicide Clearance Research: The Utility of Multifaceted Data Collection Approaches

This study explores issues associated with the data commonly used in homicide clearance research. Data collected from 2009 to 2011 case files ( n = 252) were reviewed during interviews with investigators ( n = 29). The multifaceted data collection approach produced a more comprehensive dataset than was available based solely upon case file reviews, with alterations to the data occurring in as many as 69% of the cases. The process advanced the precision of the data recorded, reduced missingness, and heightened detail on key variables. Significant differences were noted in multivariate analyses of the datasets when modeling clearances. Findings suggest contextualizing case file data is valuable.

Getting Away With Murder: Homicide Clearance by Arrest in Chicago and Its Community Areas

This work explores the decline in murder clearances through arrest in Chicago from 1965 through 2015, specifically focusing on the most recent time period since 2001. The findings suggest that clearance by arrest has decreased significantly, that elapsed time is a limited factor in clearing more murders through arrest and that factors associated with clearance by arrest in Chicago have changed over time. These results lead to a discussion on the missing variance that cannot explain murder clearance by arrest as well as future research areas that can explore why many murderers in Chicago are increasingly escaping the justice system.

Solving Homicides: The Influence of Neighborhood Characteristics and Investigator Caseload

The primary theoretical perspectives through which homicide clearance is analyzed do not give explicit attention to the neighborhood context in which people are victimized. Indeed, few clearance studies incorporate neighborhood effects. This study investigates whether neighborhood context influences the odds of homicide clearance in Rochester, NY, net of theoretically relevant victim and incident characteristics. The study also incorporates a direct measure of investigator caseload to assess the influence of organizational characteristics on clearance rates. Findings indicate that homicides, particularly of Black victims, were significantly more likely to be cleared in disadvantaged neighborhoods even as witnesses were less likely to cooperate with police in those neighborhoods. However, the odds of clearance decrease as the number of open cases each investigator is carrying increases. Case incident characteristics and the quality of evidence collected remain salient solvability factors regardless of location. Equally important is maintaining adequate staffing and keeping investigator caseloads at manageable levels. Heavy caseloads impose a significant constraint on the time that can be devoted to otherwise solvable cases and as such are analogous to the constraints imposed on prosecutors and courts by their typically heavy caseloads.

The Impact of Investigation Strategies and Tactics on Homicide Clearance

This study examines whether changes made to the investigation procedures within the Rochester Police Department’s homicide unit have an effect on homicide clearance net of theoretically significant variables related to victim and police devaluation, event characteristic, and victim lifestyle. It examines 132 homicides investigated by the homicide unit over 4 years consisting of the pre-intervention period and post-intervention period. It is hypothesized that investigation tactics will affect the odds of clearance, even after controlling for other theoretically relevant variables. The findings support this hypothesis, suggesting that the approaches and tactics police departments implement within their investigative units are important.

Homicide clearance in Western Europe

This study provides an overview of homicide clearance in four West European countries: Finland, the Netherlands, Sweden and Switzerland. Using data from the European Homicide Monitor, employing similar definitions and uniform coding schemes, this study allowed for unique cross-country comparisons in factors influencing differences in homicide clearance rates. Findings based on homicides occurring in the period 2009–14 revealed overall low homicide rates in all countries, with a wide variety in homicide clearance rates, ranging from 77 percent in the Netherlands to 98 percent in Finland. Results further showed that both event-based as well as victim-based characteristics significantly influenced the likelihood of homicide clearance, suggesting that homicide clearance rates can, for a large part, be attributed to the prevalent types of homicide in each of these European countries.

Neighborhood Context and Homicide Clearance: Estimating the Effects of Collective Efficacy

Only a handful of macro-level studies of homicide clearance exist, and the impact of community characteristics is mixed. In addition, community members are critical to clearances, but the willingness of residents to unite for the collective goal of aiding in investigations (via collective efficacy) remains to be tested. Combining data from the Chicago Police Department, Project on Human Development in Chicago Neighborhoods (PHDCN), and U.S. Census, we estimate the effect of collective efficacy on homicide clearances in Chicago neighborhoods, while taking into account neighborhood characteristics and case composition. Results indicate that economic disadvantage, residential stability, and victimization significantly decrease homicides clearances, while collective efficacy increases clearances.