What came first: the police or the incident? Bidirectional relationships between police actions and police incidents

Abstract

The present research examines the long-term, bidirectional relationships between calls for service, crime, and two police patrol strategies in Santa Monica, California: foot patrol and police stops. Using nine years of monthly data (2006 to 2014), we estimate two sets of blocklevel, longitudinal models to tease apart these relationships. In our first set of models, we use police actions and calls for service in the preceding month(s) to predict crime in the subsequent month. In our second set of models, we use calls for service and crime in the preceding month(s) to predict police actions in the subsequent month. We find that while changes in calls for service and crime often precede changes in police action, changes in crime also tend to follow them. For example, police stops appear to be particularly receptive to burglary: blocks with more burglaries receive greater numbers of police stops, and blocks with more police stops have reduced odds of experiencing burglary. We also find that the length of effects of predictors varies as a function of predictor and outcome: whereas some predictors exhibit short temporal effects (e.g., one month), other predictors exhibit much longer temporal effects (e.g., twelve months). Our results thus provide important insight into the spatial and temporal relationships between police actions and police incidents. Police actions must be neatly tailored to police incidents at precise levels if long-term deterrent effects at these levels are to be achieved.

The practice of proactive traffic stops

“…By aggregating the data at the time dimension, the study speaks only to the spatial co-occurrence between the events of interest and does not explore the potential causal and bidirectional relationship between traffic stops and crime and crashes (see, e.g. Simpson and Hipp, 2017; Wu and Lum, 2017). Future studies could model the reciprocal dynamics between police proactivity and the various forms of societal harm, and compare agencies with and without established DDACTS or data-driven programs.…”

“…In line with previous micro-geographic studies of police proactive work and crime (Carter and Piza, 2018; Simpson and Hipp, 2017), we conduct the study at the census block level, spatially joining each location of crime, proactive traffic enforcement and vehicle crash to census blocks in the two jurisdictions. Given their size, census blocks can be identified as a “micro-place” unit, along with street segments and addresses (see descriptions in Weisburd et al , 2012).…”

Reducing speeding via inanimate police presence

“…These findings are consistent with previous research that has found that the presence of police vehicles, which are also visual cues of police (e.g., see Simpson, 2019), can impact motorist behavior (Armour, 1986; Kaplan et al., 2000; Ravani & Wang, 2018; Shinar & Stiebel, 1986). In addition, these findings add to the growing body of contemporary literature that suggests that the police can have a direct impact on crime and related behavior (e.g., Andresen & Lau, 2014; Braga & Bond, 2008; Esbensen, 1987; Holland & Conner, 1996; Kelling et al., 1974; Mashhadi et al., 2017; Piza & O'Hara, 2014; Police Foundation, 1981; Ratcliffe et al., 2011; Redelmeier et al., 2003; Sherman & Weisburd, 1995; Simpson & Hipp, 2019; Stanojević et al., 2018; Taylor et al., 2011; Telep et al., 2014) and supplement existing research that has found support for CPTED principles (e.g., Clarke, 1983, 1997; Jeffery, 1971; Newman, 1972).…”

“…Measuring the ability of police to affect citizen behavior has rested at the root of much criminological research. Although the preceding section introduced the role of the police in changing motorist behavior, specifically, a large body of research has explored the effects of policing strategies, like foot patrol (e.g., Andresen & Lau, 2014;Esbensen, 1987;Jones & Tilley, 2004;Piza & O'Hara, 2014;Police Foundation, 1981;Ratcliffe, Taniguchi, Groff, & Wood, 2011;Simpson & Hipp, 2019), vehicle patrol (e.g., Kelling, Pate, Dieckman, & Brown, 1974;Taylor, Koper, & Woods, 2011) and hot spot policing (e.g., Braga & Bond, 2008;Sherman & Weisburd, 1995;Telep, Mitchell, & Weisburd, 2014), on more traditional types of crime and/or deviant behavior. For example, Piza and O'Hara (2014) observed that a saturation foot patrol program reduced violent crime in Newark, New Jersey; Telep et al (2014) reported that hot spot patrols reduced calls for service and crime in Sacramento, California; Simpson and Hipp (2019) argued that foot patrol and police stops reduced certain types of crime in Santa Monica, California; and Jones and Tilley (2004) found that the introduction of high-visibility foot patrols reduced personal robberies in an urban city center in the United Kingdom.…”

“…For example, Piza and O'Hara (2014) observed that a saturation foot patrol program reduced violent crime in Newark, New Jersey; Telep et al. (2014) reported that hot spot patrols reduced calls for service and crime in Sacramento, California; Simpson and Hipp (2019) argued that foot patrol and police stops reduced certain types of crime in Santa Monica, California; and Jones and Tilley (2004) found that the introduction of high‐visibility foot patrols reduced personal robberies in an urban city center in the United Kingdom.…”