Analysing the police patrol routing problem : a review

Police patrol is a complex process. While on patrol, police officers must balance many intersecting responsibilities. Most notably, police must proactively patrol and prevent offenders from committing crimes but must also reactively respond to real-time incidents. Efficient patrol strategies are crucial to manage scarce police resources and minimize emergency response times. The objective of this review paper is to discuss solution methods that can be used to solve the so-called police patrol routing problem (PPRP). The starting point of the review is the existing literature on the dynamic vehicle routing problem (DVRP). A keyword search resulted in 30 articles that focus on the DVRP with a link to police. Although the articles refer to policing, there is no specific focus on the PPRP; hence, there is a knowledge gap. A diversity of approaches is put forward ranging from more convenient solution methods such as a (hybrid) Genetic Algorithm (GA), linear programming and routing policies, to more complex Markov Decision Processes and Online Stochastic Combinatorial Optimization. Given the objectives, characteristics, advantages and limitations, the (hybrid) GA, routing policies and local search seem the most valuable solution methods for solving the PPRP

How concentrated are police on crime? A spatiotemporal analysis of the concentration of police presence and crime

Purpose: Police patrol has undergone an evidence-based and data driven transition in the beginning of the 21st century. While crime patterns are well researched, patterns of police presence are not. Despite the abundance of available GPS data, little is known about the spatiotemporal patterns of police forces. Given the paucity of evidence on where everyday policing takes place, we ask: what spatiotemporal patterns of police exist, how do these patterns change over time, and how do these correspond to local crime patterns? Methods: Therefore, we analysed more than 77 million GPS signals from 130 police patrol cars and more than 50,000 recorded crimes from 2019.to investigate where and when police patrols are present. All data were geocoded and map matched using high performance computing. Results: We found that police, much like crime, concentrates on a small proportion of street segments and that the spatial concentration experiences temporal instability at the micro level. Further, spatiotemporal police presence and its concentration appear to be unrelated to local levels of crime and crime concentration. Conclusions: These findings inform police chiefs and researchers alike and enable alterations of patrol deployment in order to refine the spatiotemporal focus of police on local crime. Future considerations are required to research optimal spatiotemporal alignment of police presence to effectively prevent crime

What do we really know about police patrol? A systematic review of routine police patrol research

Purpose: Research on routine police patrol has experienced little attention in criminology for the past four decades. Despite the fact that little is known about this mode of policing, a consensus seems to prevail regarding its ineffectiveness for crime deterrence and crime prevention. To emphasize this gap of research, this study systematically reviews existing literature on routine police patrol. Methods: A systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines of scientific studies (n=4) was conducted. Evidence was synthesized quantitatively (e.g., tabular) and qualitatively (e.g., narrative argumentation). Results: The synthesized results provide no ground for the diagnosed ineffectiveness of routine police patrol, that seems to be believed throughout criminological studies. Despite the outdated character of the majority of reviewed studies, results show inconsistencies and fail to clearly establish positive or negative quantitative crime deterrent effects. Conclusion: Contemporary research does not adequately understand the effects of routine police patrol and builds leading police research on a limited number of methodically flawed studies from the mid 1970’s. Future research should establish the effectiveness of this mode of policing and optimal spatial allocation of police officers following a sound methodological framework

Policing directions : a systematic review on the efficacy of quantitative police presence

This systematic review assesses the efficacy of quantitative police presence. The review also investigates concepts of police presence and differences between reported effects. PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines and protocols are used to systematically identify and review eligible studies on police presence. Further, quality assessment and findings synthesis are used to map limitations of current research as well as grounds for future avenues. The systematic search strategies yielded 49 studies focusing on testing the effects of police presence or evaluating its measurement. We find evidence that police presence has mostly positive effects on reducing crimes related to motor theft, property, violence, and guns. Police presence also reduces calls for service and improves traffic behaviour. Police presence focused on specific areas, times, and types of crime achieves maximum efficacy. The reviewed studies show a high degree of heterogeneity in reporting, which limits comparability of findings across studies. Research on police presence presents evidence for crime preventative effects of focused police actions. Police forces can be focused on certain areas, times, and types of crimes. We encourage future research to focus on police presence en route and its effects, including crime prevention, traffic regulation, and fear of crime

Optimising daily police patrol : towards better matching police supply and demand by directing police in space and time

Een koerier weet bij aanvang van zijn ronde welke pakjes hij op welke adressen moet afleveren. Dit is niet het geval voor politie-inspecteurs van de afdeling Interventie. Bij aanvang van hun shift weten ze niet waar en wanneer een noodoproep zal binnenkomen, om welk type incident het zal gaan en waar de eenheid zich nadien moet positioneren om opnieuw een optimale regiodekking te garanderen. Bovendien maakt de combinatie van misdaadpreventie en het afhandelen van noodoproepen het politiepatrouilleprobleem complexer dan andere toewijzings- en routeringsproblemen. Hoewel 'noodoproepen' doet vermoeden dat het steeds om dringende en levensbedreigende incidenten gaat, betreft dit slechts een klein aandeel van het totaal aantal oproepen. Dit toont aan dat politiewerk grotendeels bestaat uit een structurele, niet-urgente vraag en inspecteurs voornamelijk optreden als bemiddelaars en hulpverleners. Het ontwikkelen van een patrouillestrategie bestaat erin het aanbod af te stemmen op deze vraag. Een onderaanbod is logischerwijs ongewenst, maar omgekeerd is het ook moeilijk te bepalen wanneer ergens voldoende politieaanwezigheid is. Het is belangrijk te beseffen dat (over)aanbod op één plaats betekent dat andere plaatsen op dat moment niet met die middelen kunnen worden bediend. Daarom wordt in dit onderzoek onderzocht waar en wanneer de beschikbare middelen optimaal kunnen worden ingezet

What comes first : crime or police? A spatiotemporal perspective on reported crimes and tracked police presence

The majority of motor patrol officers spent their shifts being out in the field. Patrol officers are either assigned and responding to emergency calls from citizens or being unassigned and patrolling police beats at their own discretion. What remains unclear is the existence or the extent of crime preventive effects of police presence across microgeographic units. To this end, more than 84,000 reported crimes and 290 million individual GPS signals from police patrol cars are analyzed. The data is obtained from the Antwerp Police Department (APD) for the study period from 2019 to 2020. The crime data can be categorized into citizen-reported or officer-reported events and the GPS signals allow the calculation of patrol time being spent unassigned or assigned. All used data is geocoded and subsequently map matched to one of the more than 30,000 street segments in Antwerp. Spatiotemporal analyses at the street segment and hour level allow us to investigate the interplay between reported crime and tracked police presence. We report the results from this big data analysis and critically assess contemporary policing strategies

Unravelling spatiotemporal patterns of everyday police patrol in Antwerp

Police patrol distinguishes itself from other routing problems due to the interaction between reactive and proactive patrol. Therefore, it is important to understand the spatiotemporal patterns of police patrol and criminal activity to logistically optimize resource allocation. Moreover, crime deterrent effects of preventative or proactive motor patrol have to be quantified and, to increase its effectiveness, it is of great value to determine the optimal dosage on the street segment level. Police presence and its deterrent effect on crime in time and space influences the optimal spatial deployment of patrol cars. In this research on police patrol, we analyse crime incidents, 911 calls, and GPS data of the Antwerp Local Police Department (ALPD) in Belgium. In 2018, the ALPD registered more than 43,000 crimes and tracked the routes of more than one hundred police vehicles. Successive data cleaning, map matching, and geocoding of the data make it possible to visualize spatiotemporal patterns of crimes, 911 calls, and police patrol. Combining these patterns is a first important step in developing an algorithm for police patrol as well as determining the relationship between police presence and crime prevention