Author: Paul Marchant

Abstract This confirmatory study estimates the effect on Police Recorded Crimes (PRCs) of a relighting programme that installed nearly 80,000 white-light lamps, replacing predominantly orange ones, in the years 2005 to 2013, throughout the UK city of Leeds. Time series of weekly PRCs in all 107 Middle-layer Super Output Areas, while road lighting was being […]

Abstract This article discusses the results and implications of large scale studies which have investigated the effect on road safety of changing road lighting. In particular it highlights the failure to detect any impact on road traffic collisions of changing to white light. It calls for more rigorous statistical work to be carried out before […]

Abstract Large-scale installation of broad-spectrum (white) road lighting has been claimed to bring about a substantial reduction in road traffic collisions (RTCs). This confirmatory study estimates the effect on personal injury RTCs of a relighting programme that installed nearly 80,000 new white lamps, between the years 2005 and 2013, throughout the large UK city of […]

Abstract The paper of Jackett & Frith (2013), which purports to show considerable gains for road safety with increasing road luminance, is seriously flawed. It asserts that increasing the luminance on roads causes improvements in road safety. Its cross-sectional design fails to rule out major potential confounders. Using a longitudinal design would be a far […]

Abstract Background A step change in the night environment is taking place, with the large-scale installation of bright, broad-spectrum road lighting such as white light-emitting diodes (LEDs). One justification for this is a reduction in road traffic collisions (RTCs). This study aimed to estimate the effect of new lighting on personal injury RTCs within a large […]

Abstract Artificial light at night (ALAN) is increasing exponentially worldwide, accelerated by the transition to new efficient lighting technologies. However, ALAN and resulting light pollution can cause unintended physiological consequences. In vertebrates, production of melatonin—the “hormone of darkness” and a key player in circadian regulation—can be suppressed by ALAN. In this paper, we provide an […]

Would a billion-dollar investment in improved street lighting make Australian roads safer at night? Paul Marchant finds the evidence wanting The full text is available here. Author: Paul Marchant Title: Do brighter, whiter street lights improve road safety? Date: 04 October 2019 Publication: Significance Volume: 16 Number: 5 Pages: 8 – 9 DOI: 10.1111/j.1740-9713.2019.01313.x

Abstract This paper gives some background to claims of benefit from road lighting and why large beneficial claims may be suspect. It places this in the context of general concerns about the unreliability of claims in science using knowledge gained, particularly from investigations in the field of health-care.It points to the need to plan, proceed […]

Abstract Crime counts published by the Home Office for the Metropolitan Police Crime and Disorder Reduction Partnership areas have been collated across the years 2003-2009. The crime counts over time have been modelled taking into account the ‘multilevel’ (years within areas) nature of the data. The key variable of interest, as a predictor of within-area […]

Abstract Non-randomized trials can give a biased impression of the effectiveness of any intervention. We consider trials in which incidence rates are compared in two areas over two periods. Typically, one area receives an intervention, whereas the other does not. We outline and illustrate a method to estimate the bias in such trials under two […]

Introduction This paper gives some background to claims of benefit from road lighting and why large beneficial claims may be suspect. It places this in the context of general concerns about the unreliability of claims in science using knowledge gained, particularly from investigations in the field of health-care.It points to the need to plan, proceed […]

Introduction Paul Marchant disputes the methods, and therefore the outcome, of an influential study that is the government’s rationale for increased street lighting. The full text is available here. Author: Paul Marchant Title: Shining a light on evidence-based policy: street lighting and crime Date: 14 March 2008 Publication: Criminal Justice Matters Volume: 62 Number: 1 […]

Abstract Crime is a serious business. It causes great distress and fear. It costs a lot to deal with its consequences. In these regards crime shares much with the problem of ill-health and disease. The application of sound science and statistics has allowed great strides to be made in dealing with problems of ill health. […]

Abstract When we look around an imperfect world, we feel an understandable impulse to improve matters. We may therefore decide to intervene by prescribing medical treatment or by introducing crime reduction measures. But how do we know that what we do is likely to work? In medicine the standard answer is to do a trial; […]

Abstract This article discusses the important differences between evaluating area-based crime reduction interventions through comparison of areas, and evaluating treatment effectiveness by a classic randomised controlled trial (RCT). The differences must be respected in the analysis of data. Wrong results will be given for a comparative area- based crime reduction trial if it is thought […]

Abstract The major systematic review on street lighting and crime, Home Office Research Study 251, suggests that claims for the effectiveness of lighting against crime are justified. The review at first sight appears to be an appropriate statistical synthesis of all studies on street lighting and crime across the world. However on close examination, the […]