Predictive Crime Mapping: Arbitrary Grids or Street Networks?

Objectives

Decades of empirical research demonstrate that crime is concentrated at a range of spatial scales, including street segments. Further, the degree of clustering at particular geographic units remains noticeably stable and consistent; a finding that Weisburd (Criminology 53:133–157, 2015) has recently termed the ‘law of crime concentration at places’. Such findings suggest that the future locations of crime should—to some extent at least—be predictable. To date, methods of forecasting where crime is most likely to next occur have focused either on area-level or grid-based predictions. No studies of which we are aware have developed and tested the accuracy of methods for predicting the future risk of crime at the street segment level. This is surprising given that it is at this level of place that many crimes are committed and policing resources are deployed.

Methods

Using data for property crimes for a large UK metropolitan police force area, we introduce and calibrate a network-based version of prospective crime mapping [e.g. Bowers et al. (Br J Criminol 44:641–658, 2004)], and compare its performance against grid-based alternatives. We also examine how measures of predictive accuracy can be translated to the network context, and show how differences in performance between the two cases can be quantified and tested.

Results

Findings demonstrate that the calibrated network-based model substantially outperforms a grid-based alternative in terms of predictive accuracy, with, for example, approximately 20 % more crime identified at a coverage level of 5 %. The improvement in accuracy is highly statistically significant at all coverage levels tested (from 1 to 10 %).

Conclusions

This study suggests that, for property crime at least, network-based methods of crime forecasting are likely to outperform grid-based alternatives, and hence should be used in operational policing. More sophisticated variations of the model tested are possible and should be developed and tested in future research.

     

Initiatives that Counter Violent Radicalization but are Perceived as Suitable by Targeted Communities

To redress the scourge of violent extremism, an array of policies, programs, and practices have been implemented. Yet, these initiatives could sometimes conflict with the preferences of individuals who may be susceptible to radicalization. To illustrate, some initiatives might challenge the values of these individuals. The degree to which these individuals feel significant or important might thus decrease—a decrease that has been shown to rouse the pursuit of violent radicalization. To prevent this complication, two studies were designed to uncover programs, policies, or practices that align to the preferences of people who may be more susceptible than average to violent radicalization. In Study 1, three individuals who had been charged with crimes related to terrorism, but had since relinquished extremism, were asked to suggest initiatives they feel could prevent violent radicalization in Australian Muslims. Similarly, in the second study, young Australian Muslim adults who rejected extremist ideologies were asked the same question. The participants advocated initiatives that foster tolerance towards diverse perspectives, inspire individuals to trust their values and intuition, encourage civic engagement, improve the credibility of imams, and enable people to derive strength from their community. A review of previous literature indicates that many of these initiatives might not only resonate with the preferences of individuals who may be vulnerable to violent extremism but could also foster a sense of significance and meaning in life—an experience that tends to prevent radicalization.     

Permeability and Burglary Risk: Are Cul-de-Sacs Safer?

That crime is concentrated in space is now accepted as commonplace. Explanations for why it clusters at particular locations are various reflecting the range of factors which are held to influence crime placement. In this article, we focus on the role of the permeability of the street network on the location of crime. We first review the research conducted hitherto, summarising the different approaches to analysis and the findings that have so far emerged. Then we present original analyses conducted at the street segment level to examine the issues at hand. In contrast to much of the prior research, in this study we examine the patterns for a large study area in which there is considerable variation in street network configuration. Moreover, and in contrast to all of the previous research, the approach to analysis takes into account the multi-level structure of the data analysed. The findings demonstrate that increased permeability is associated with elevated burglary risk, that burglary risk is lower on cul-de-sacs (particularly those that are sinuous in nature), and that the risk of burglary is higher on more major roads and those street segments that are connected to them. In the conclusion of the paper we outline an agenda for future research.     

The Morality of Lying and the Murderer at the Door

Law and Philosophy - The article engages with some of the main claims in chapter 1 of Seana Shiffrin’s book Speech Matters. There, Shiffrin sets out a case for a general moral prohibition on...     

Restrictions on legal aid in family law cases in England and Wales: creating a necessary barrier to public funding or simply increasing the burden on the family courts?

The Legal Aid, Sentencing and Punishment of Offenders Act 2012 (LASPO) resulted in significant cuts to the availability and scope of legal aid in family law proceedings. Some four years after the cuts were implemented, there has been a great deal of research about their devastating impact on vulnerable groups and individuals. This paper considers the other victim of the cuts, the family court itself. It is currently bulging under pressure from both an increase in applicants who have been forced to represent themselves in family proceedings and also from a rise in applications for injunctions linked to domestic violence. This paper will draw on case law to demonstrate that the reforms implemented through LASPO have seemingly only succeeded in passing the burden from one publicly funded agency, the Legal Aid Agency, to another, HM Courts and Tribunals Service. The family court system is currently at breaking point and further government review is urgently needed if people are going to be able to continue to use the system effectively.     

Australian forensic textile damage examinations – Finding a way forward since PCAST

Textile damage examinations are requested in a range of crime types such as assault, sexual assault and homicide. They typically involve the examination of clothing for damage such as cut, tear or thermal damage, often then followed by experimental scenario testing to help ascertain the cause of the damage. Understanding the underpinning science is central to the accurate interpretation of the complex mechanism of damage formation. In a stabbing incident for example, an understanding of the dynamic relationship between the knife blade, fabric and skin (or skin simulant) is critical.Recent reports, including the President's Council of Advisors on Science and Technology (PCAST) report, have scrutinised forensic feature-based comparison techniques. Whilst textile damage was not a focus area, it can be considered a feature-based evidence class, and one which is currently largely reliant upon a practitioner's opinion, experience and professional judgement.This paper will review the current state of textile damage examinations in Australia and survey research being conducted to address the issues raised in the context of the PCAST report. The central contribution of observational data to the evidence class of textile damage will also be explored, as well as some practical measures to counter the effects of cognitive bias.     

“You must be joking”: the role of humour in the law classroom

There is a body of literature, including persuasive empirical evidence, linking the use of positive humour in tertiary classrooms with the creation of a relaxed learning environment, student motivation, attendance and engagement as well as positive student evaluations of teacher performance. However, the literature on the use of humour in teaching law is generally limited to anecdotal evidence. Drawing on the literature on using humour in teaching courses that students perceive as “difficult” in other disciplines, in this article we explore the benefits and pitfalls of using humour in the law classroom and provide illustrations of how humour might be used appropriately and effectively in teaching law.