The relationship between temperature and assault in New Zealand

Abstract

A number of previous studies have reported a positive relationship between ambient temperature and the incidence of violent crimes such as assault. This has led some authors to suggest that anthropogenic climate change may result in an increase in violent crime rates. In this study, we report an investigation of the relationship between temperature and assault incidence in New Zealand. Both police data listing recorded assaults as well as data from the Ministry of Health listing hospitalisations due to assault were examined. Geographical, seasonal, and irregular daily variation in temperature were all positively related to the incidence of assault, although only the effect of irregular variation in temperature was robust to controls for plausible confounds. The estimated effect of irregular daily variation in temperature was approximately 1.5 % extra recorded assaults for each 1°C increase in temperature. It remains difficult, however, to make accurate predictions about future assault rates in a warming world. For example, humans may react to sustained changes in climate in ways that differ markedly from their reaction to short-term variation in temperature. Climate change may also affect rates of violence via mechanisms other than those that currently drive the relationship between temperature and violence. Furthermore, assault rates may continue to change in response to factors unrelated to climate change, such as those responsible for the long-term historical decline in human violence.

The Influence of Interannual Climate Variability on Regional Violent Crime Rates in the United States

“…Investigations at the scale of individual cities, such as Dallas, TX (Gamble & Hess, ); St. Louis, MO (Mares, ; Mares, ); Philadelphia, PA (Schinasi & Hamra, ); and Tangshan, China (Hu et al, ), have uniformly demonstrated a positive relationship between temperature and violent crime. Still, other studies have produced similar findings at a broader scale, either by examining a conglomeration of data at the city or county level in the United States (Hipp et al, ; Jacob et al, ; Ranson, ), New Zealand (Horrocks & Menclova, ; Williams et al, ), or South Africa (Bruederle et al, ), or by examining annual, nationally aggregated data for the United States (Anderson et al, ; Rotton & Cohn, ), Finland (Tiihonen et al, ), Malaysia (Habibullah, ), England and Wales (Field, ), or multiple countries around the globe (Mares & Moffett, ). A recent meta‐analysis by Hsiang et al () concurred with these findings; variation in relationship strength between different crime types is a common conclusion (e.g., Rotton & Cohn, ), though aggravated and simple assault consistently yield the strongest relationship with temperature.…”

Predictive Extrinsic Factors in Multiple Victim Shootings

“…Mares ( 2013 ) found a relationship between temperature anomaly and crime overall, but none for homicide. Williams, Hill, and Spicer ( 2015 ) found a positive relationship between temperature anomaly and assaults. Schinasi and Hamra ( 2017 ) found that violent crime was strongly associated with temperature deviations.…”

Climate change and victimization risk: A disaggregated look at NCVS data

“…Not surprisingly, with rapidly accumulating evidence of a global climate change, more and more studies focus on the effects of climate change on the rates of violent offending (Anderson and Delisi, 2011; Anderson et al, 1997; Hsiang et al, 2013; Mares, 2013a, 2013b; Mares and Moffett, 2016, 2019; Ranson, 2014; Rotton and Cohn, 2003; Williams et al, 2015). Previous US national-level studies have relied on Uniform Crime Report (UCR) data during their examination of the relationship between climate change and crime (see Ranson, 2014; Rotton and Cohn, 2003; Harp and Karnauskas, 2018; Mares and Moffett, 2019).…”