This study used homicides as an indicator for the occurrence of a standardized set of highly visible, socially-intensive, acute police investigative activities in examining whether police calls-for-service changed in response.
Calls-for-service represent the most basic form of public cooperation with the police. How cooperation varies as a function of instances of police activity remains an open question. The situational diversity of police activity in the field and matching the situational diversity of crime and disorder makes it challenging to estimate causal effects. The current study adopted a place-based difference-in-differences approach that controlled for local fixed affects and common temporal trends. Estimates of the model using data from Los Angeles in 2019 shows that calls-for-service increased significantly in the week following a homicide. The effect pertains to both violent crime and quality-of-life calls for service. Partitioning the data by race-ethnicity shows that calls-for-service increased most when the homicide victim was Black. Partitioning the data by race-ethnicity and type of homicide shows that some types of calls are suppressed when the homicide is gang-related. The results point to opportunities for police to build public trust in the immediate aftermath of homicides, because the public is reaching out for greater assistance. (publisher abstract modified)