Research SummaryWidespread protests and demands for accountability in the wake of broadly publicized police killings of unarmed civilians coincided with the marked upturn in homicide levels, especially in large U.S. cities, in 2015. Many observers, including prominent political figures, claimed that de‐policing caused the homicide rate to rise: Fearing increased legal liability and publicity, the police employed less proactive enforcement and made fewer arrests, producing an increase in homicide levels. We use structural equation modeling to estimate the simultaneous relationship between arrest and homicide rates between 2010 and 2015 in 53 large cities. We find no evidence of an effect of arrest rates on city homicide rates for any offense category for any year in this period, including 2015, the year of the spike in homicide levels.Policy ImplicationsThe results of our analysis reveal that declining rates of arrest did not produce the rise in homicide levels. But arrests, the chief formal reaction to crime, can play an important supporting role in crime prevention. Ample research findings have demonstrated the effectiveness of proactive policing practices, such as targeted patrol, in reducing crime rates. The success of such tactics depends, in turn, on citizens’ belief that criminal offenders face an appreciable risk of arrest. It is equally important, however, that residents of communities that have experienced unwarranted police violence believe that law enforcement is fairly applied. Lack of trust and confidence in the police militates against crime prevention as a co‐production of police and community and may promote violence as a form of self‐help.