Homicide Clearance Rates Research Articles

Police personnel allocation and homicide clearance

PurposeThis paper applies novel techniques from the field of operations management to examine the allocation of patrol and investigative personnel to identify which is most effective in improving police performance around homicide clearance.Design/methodology/approachA panel sample of homicide clearance rates from the 100 largest US cities between 2000 and 2013 were analyzed in two steps: first, a random-effects regression model was performed to locate influential factors; second, optimum analysis was applied to locate the optimal values that yield maximal homicide clearance.FindingsBoth patrol and investigative personnel levels have a significant impact on homicide clearance. Maximal clearance can be achieved by allocating departmental personnel to investigative roles.Research limitations/implicationsGiven recent trends around “defunding” police and public sector austerity measures, future research should continue to explore the utility of optimum analysis for efficient allocation of policing personnel.Originality/valueThis study provides proof of concept for the use of optimum analysis in policing research.

Explaining the Extraordinary Decline in Chicago’s Homicide Arrest Rates, 1965 to 1994 and Beyond: Trends in Case Mix Versus Standards for Arrest

Chicago’s homicide arrest rate dropped from 91% in 1965 to 57% in 1994 and dropped still lower in recent years. This pattern mirrors the trend in the national homicide clearance rate. A plausible explanation for this great decline is the trend in homicide case mix, which arguably has made it intrinsically more difficult to solve homicide cases. Our analysis describes the change in case mix for the period 1965 to 2020 and analyzes the effect on the arrest rate for the first 30 years of this period, all by use of a unique homicide case microdata set. We document the large changes in case mix: for example, the percentage of all homicides in which a male victim was shot outdoors increased from 18% (1965) to 69% (2020). But the change in case mix does not account for Chicago’s great decline during the earlier decades, as we demonstrate by use of a novel arrest rate index. In fact, the arrest rates in each of the categories defined by location, sex, and weapon type exhibited similar declines through 1994. (Subsequent years of arrest data are unavailable for now.) Our preferred explanation for the great decline is that the operational standard for making an arrest increased during this period. That interpretation is well supported by evidence explaining the corresponding national trend, though direct evidence is lacking for Chicago. This interpretation challenges the use of the arrest rate as a police performance indicator and offers a positive interpretation of the great decline.

The Sixty-Year Trajectory of Homicide Clearance Rates: Toward a Better Understanding of the Great Decline

In 1962, the FBI reported a national homicide clearance rate of 93%. That rate dropped 29 points by 1994. This Great Decline has been studied and accepted as a real phenomenon but remains mysterious, as does the period of relative stability that followed. The decline was shared across regions and all city sizes but differed greatly among categories defined by victim race and weapon type. Gun homicides with Black victims accounted for most of the decline. We review the evidence on several possible explanations for the national decline, including those pertaining to case mix, investigation resources, and citizen cooperation. Our preferred explanation includes an upward trend in the standard for arrest, with strong evidence that although clearance-by-arrest rates declined, the likelihood of conviction and prison sentence actually increased. That result has obvious implications for the history of policing practice and for the validity of the usual clearance rate as a police performance measure.

A Tale of Two Cities: Policing and Firearm Homicides in Boston and Philadelphia.

Recent political movements have raised questions about the effectiveness of police funding, but the impact of law enforcement budgets on firearm violence is unknown. We hypothesized that department funding and measures of police activity would be associated with decreased shootings and firearm homicides (FH) in two major cities with different police funding patterns. We collected data from these sources: district attorney's offices, police departments, Federal Bureau of Investigation Uniform Crime Reporting program, the Centers for Disease Control, the Annual Survey of Public Employment & Payroll, and the American Community Survey. Data included demographics, police department budgets, number of officers, homicide clearance rates, firearms recovered, shootings, and FH, 2015-2020. Totals were normalized to population and number of shootings. We used panel linear regression to measure associations between policing variables, shootings and FH while adjusting for covariates. FH significantly increased in Philadelphia. In Boston the trend was less clear, though there was an increase in 2020. Police budget normalized to shootings trended towards a decrease in Philadelphia and an increase in Boston. The number of firearms recovered annually appeared to increase in Boston but peaked mid-study in Philadelphia. In multivariable analyses, police budget was associated with neither shootings nor FH. However, increased firearm recovery was associated with lower shooting (β = -.0004, p = 0.022) and FH (β = -.00005, p = 0.004) rates. Philadelphia and Boston demonstrated differences in police funding, 2015-2020. While budget is not associated with shootings or FH, firearm recovery is, suggesting that removal of firearms from circulation remains key. The impact this has on vulnerable populations requires further investigation. III, retrospective cross-sectional.

Does greater police funding help catch more murderers?

AbstractThis paper examines the impact of police funding on the fraction of homicides that are cleared by arrest. Using data covering homicides in approximately 50 of the largest US cities from 2007 to 2017, I find no evidence that greater police funding resulted in higher homicide clearance rates. This finding is robust to linear regression and instrumental variable approaches, different ways to measure police budgets, and across victims of different races and in different types of neighborhoods. In summary, the way large city police departments have historically spent their funds, more funding has not helped catch more murderers.

Homicide Clearance Rates in the United States, 1976-2017: Examining Homicide Clearance Rates Relative to the Situational Circumstances in Which They Occur.

This study examines homicide clearance rates in the United States using the FBI's supplementary homicide reports data spanning from 1976 to 2017. The goal of this study is to examine the effects of circumstances in which homicides occurred on homicide clearance rates, and the effects of victim's race, age, and gender on homicide clearance rates. The analyses are based on 769,753 total homicide cases that were reported to the FBI. The actual data set includes information for 757,801 victims and 513,863 offenders total. The results of this study show that a typical profile of a homicide victim whose case is more likely to remain unsolved is that of a black male between the ages of 21 to 30 who is killed in a juvenile gang-related killing circumstance. By gender, this study shows that the clearance rate for homicide cases involving female victims is 8.4% higher than for male homicide victims.

Stereotypes and the Administration of Justice

Stereotypes play a pervasive role in the administration of justice, influencing police stops and searches, the use of force, bail and sentencing decisions, juror behavior and selection, felony disenfranchisement, and attitudes towards mass incarceration. We provide a selective survey of the literature on stereotypes and criminal justice, and discuss implications for witness cooperation, homicide clearance rates, and rates of murder victimization.

Neighborhood variation in unsolved homicides: a retrospective cohort study in Indianapolis, Indiana, 2007\u20132017

BackgroundHomicide 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.MethodsThis 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.ResultsIn 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.ConclusionsOur 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.

The Influence of Investigative Resources on Homicide Clearances

Objectives This paper investigates the influence of case characteristics and investigative resources on homicide clearance rates.

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.

Homicide clearance in Sweden 1990–2013 with special reference to firearm-perpetrated homicides

ABSTRACTStudies on homicide clearance in the Scandinavian context are very rare. In this article, we explore the homicide clearance rate in Sweden with special reference to firearm-perpetrated cases. The study is based on homicide research data collected by the Swedish National Council for Crime Prevention, comprising all 2160 homicides known to the Swedish authorities during the period 1990–2013. The annual clearance rate varied between 74 and 90%, with an overall minor decrease since the 1990s. However, there has been a considerable decrease in the clearance rate for firearm-perpetrated homicides. It can be concluded that this decrease is due to a shift in the characteristics of firearm-perpetrated offences, with homicides committed in public places against criminally active male victims having become more frequent. This finding is generally consistent with theories which argue that homicide clearance rates are predominantly affected by case-specific, non-discretional factors beyond the control of the police. The practical implications of the study are that investigative efforts should be more intense in cases where a male has been shot in a public place, and that homicides related to criminal milieus should be investigated by specialized units.

Can Homicide Detectives Improve Homicide Clearance Rates?

The available scientific evidence on the value of detectives in clearing crimes generally suggests that most crimes are solved through the random circumstances of crime scenes rather than special follow-up investigation. Other research, however, suggests that the work of criminal investigators can increase the likelihood that crimes might be cleared through arrest. After years of homicide clearance rates that were lower than the national average, the Boston Police Department engaged a problem-oriented policing approach to improve their post-homicide criminal investigation processes and practices. Our quasi-experimental statistical analyses suggest that the intervention significantly increased key investigative activities and improved Boston homicide clearance rates relative to existing homicide clearance trends in other Massachusetts and U.S. jurisdictions.

Effective Police Homicide Investigations

At present, the average homicide clearance rate in the United States is approximately 65%, down roughly 15% from the mid-1970s. This research seeks to inform how police can best improve homicide clearance rates by identifying best practices in homicide investigations. To accomplish this goal, as part of a federally funded project, seven geographically representative law enforcement agencies were identified that had at least 24 homicides in 2011 and had a clearance rate of 80% or higher from which effective investigative practices could be gleaned. Qualitative findings indicate that a strong community policing presence, collaboration with external agencies, and an innovative culture facilitate high rates of homicide clearance. Implications for policy and future research are discussed.

What clears burglary offenses? Estimating the influences of multiple perspectives of burglary clearance in Philadelphia

Purpose – Although many studies have examined the correlates of homicide clearance rates, few analyses have examined the factors related to the clearance of burglary offenses. The purpose of this paper is to address several gaps in the literature to determine if burglary clearance rates are due to discretionary, non-discretionary, and/or neighborhood contextual factors. Design/methodology/approach – Data are analyzed from more than 10,000 burglary incidents in Philadelphia from 2010 using multilevel models to simultaneously test for the influence of multiple perspectives of the factors of crime clearance. Findings – The results indicate that variables representing broken windows enforcement, discretionary factors, and non-discretionary factors are related to the increased likelihood that burglaries are cleared, but processes associated with social disorganization within communities is not. Research limitations/implications – The findings contribute to the literature by showing that future examinations of the factors of burglary clearance should consider community contextual factors, and specifically, that broken windows police enforcement appears to be a more important predictor of burglary clearance than do factors related to social disorganization theory. As a result, it is suggested that law enforcement also consider their tactics regarding low-level offenses if they wish to address the clearance rate of burglaries. Originality/value – This analysis is among the first to examine multiple perspectives of the factors of crime clearance on burglary incidents.

Adjusting Rates of Homicide Clearance by Arrest for Investigation Difficulty

Scholars have criticized the use of homicide clearance rates to measure police performance, as many incident- and jurisdiction-level characteristics beyond police control influence these rates. The current study estimated adjusted measures and rates of homicide arrest clearance, accounting for jurisdictional and incident characteristics related to investigation difficulty, for 85 agencies. Comparing agencies’ raw and adjusted measures indicates that 16% would be miscategorized as being above or below average in performance if the assessment of performance used raw rates. Adjusted homicide clearance rates, while not a singular indicator of overall success, offer a better police agency performance measure than raw rates.

Establishing the Victim–Offender Relationship of Initially Unsolved Homicides

This analysis examines the extent to which homicides initially reported as unknown offender in end-of-year reports, once cleared, are more likely to have been perpetrated by strangers than other cleared homicides. Using solved and unsolved homicides in Indianapolis ( N = 829), we determined victim–offender relationships in homicides reported as unsolved in year-end reports, when solved, were not significantly different from homicides reported as having a suspect in year-end reports. Indianapolis homicides were classified disproportionately as acquaintances. Findings help negate the ongoing myth that unsolved homicides are disproportionately stranger homicides. Results suggest decreased homicide clearance rates are not due to increased stranger homicides.

Why homicide clearance rates decrease: evidence from the Caribbean

Police agencies and researchers have devoted significant attention to understanding and improving homicide clearance rates, which often serve as an overall barometer of police performance. Using quantitative and qualitative data, this study examines the factors that contributed to a rapid decline in homicide clearances in the developing island nation of Trinidad and Tobago. A variety of explanations are explored, including characteristics of homicide incidents, the communities where they occur, and the agencies that process these cases. The findings indicate that substantial changes in the nature of homicides, combined with insufficient organisational capacity within the criminal justice system to detect and respond to these changes, explain the declining homicide clearance rate. Theoretical explanations for homicide clearances must represent a blend of insights from criminology and organisational science to account for both the offence itself, as well as how it is processed by the police and other agencies.

Explaining the Changing Nature of Homicide Clearance in Canada

Canadian homicide clearance rates are higher than for any other type of crime, but clearance rates have been decreasing since the late 1960s and they are not uniform across the country. This article examines homicide clearance in Canada using data derived from the Canadian Homicide Survey to determine whether the evident temporal and geographical variations in clearance are explained by either victim characteristics or offense details. There are two competing theories regarding homicide clearance characteristics. On one hand, it is argued that the police use discretion when determining which cases deserving more attention. The alternate theory is that police apportion the same effort to all homicide cases, regardless of the victim’s status owing to the heinous nature of the crime; therefore, only case details impede the process of determining culpability. Using logistic regression analysis, this examination first focuses on the influence of time and geography on clearance probabilities and then compares the effect of victim characteristics and offense characteristics on clearance outcomes. Empirically nested models indicate that victim characteristics are not a robust predictor of clearance; offense characteristics are found to be more influential. However, both temporal and geographical factors remain important predictors of homicide clearance. The impacts of increasing gang- and drug-related homicides are discussed, as are implications for future research.

To Know the Unknown: The Decline in Homicide Clearance Rates, 1980—2000

Against the backdrop of the precipitous decline in urban homicide clearance over the past several decades, this study examines factors that may be linked to within-city, over-time variation in homicide clearance rates from 1980 to 2000. Conceptual arguments focusing on case-level characteristics of homicides as well as the broader macrosocial context are delineated and empirically tested. Results from a fixed-effects regression analysis reveal that changes in clearance rates are linked to changes in the situational characteristics of murder incidents such as the percentage of cases involving strangers, firearms, other felonies, and arguments. In addition, within-city changes in immigration are found to be associated with lower clearance rates, whereas drug market arrests are associated with higher clearance rates. Contrary to politically popular assertions, clearance rates do not appear to be a function of changes in police personnel or workload.

Exploring the Use of DNA Evidence in Homicide Investigations

Since the 1960s there has been a consistent gradual decline in national homicide clearance rates and the trend continued throughout the 1990s and into the 21st century, despite the development of DNA evidence. Although the media portrays DNA testing as an investigative “super weapon” for police, there is little empirical research examining its actual use by detectives or its impact on case clearance. This article examines New York Police Department (NYPD) case files for Manhattan homicides between 1996 and 2003 to investigate how often detectives used DNA evidence in the course of their investigations, as well as how its use influenced the likelihood of case clearance. Results suggest that DNA evidence was rarely used by NYPD detectives and that it was not related to case clearance. These findings suggest that NYPD detectives used DNA evidence as a “tool of last resort,” relying on it only when all other investigative means had been exhausted. The authors conclude that the explanation for these findings is complex and that the diffusion framework may be helpful in understanding detectives’ use of DNA evidence in New York and elsewhere.