Scientific inquiries into the relationship between climate and crime began during the early nineteenth century. Usually climate has referred to the monthly or seasonal mean temperatures and crime has been classified into two types: crimes against the person (or violent crimes such as homicide, rape, assault, and robbery); and crimes against property (such as burglary, larceny-theft, and motor vehicle theft).

During the nineteenth century A.M. Guerry in France and A. Quetelet in Belgium, in two independent studies, observed the coincidence of higher frequencies of crimes against persons in warmer areas and during warmer months. Moreover, crimes against property increased in winter months and in cooler areas. Quetelet conceptualized these observations into the Thermic Law of Delinquency (Cohen, 1941; Harries, 1980). Neither Guerry nor Quetelet felt that climatic conditions were the principal causes of delinquency. Both criminologists are credited with starting the geographic school of criminology where the ecological facts of crime are pursued — namely, the relationship between crime and social conditions (Gibbons, 1978).

Other European scholars, during the late nineteenth and early twentieth centuries, corroborated Guerry’s and Quetelet’s findings and agreed that climate was not the principal cause of crime (Cohen, 1941). Yet studies asserting a direct causal linkage emerged and persisted.

E.G. Dexter, studying 40 000 assault cases in New York City between 1891 and 1897, suggested that temperature was the most significant condition aggravating the emotions and erupting into fighting (Cohen, 1941; Harries, 1980). A stronger and more enduring endorsement of the causal relationship came from Ellsworth Huntington (1945) who claimed physiological and psychological conditions vary with climate and weather, hence the propensity for riots and assaults to increase with temperature. Huntington’s vehement advocacy of climatic determinism as the cause of crime overshadowed the works of others including Cohen, whose work in 1941 contradicted climatic determinism.

During 1941, using the Federal Bureau of Investigation’s Uniform Crime Reports, Cohen observed the expected highs for violence during the midsummer and property crimes during the midwinter. However, the most important finding was that regional variations of frequencies and types of crimes were more pronounced and significant than the seasonal variations. Cohen believed that the regional variations were the surrogates for significant social forces (1941). Despite findings like these the academic community’s reaction to Huntington’s environmental determinism was so strong and negative that inquiries into the relationship between climate and social phenomena in general, and climate and crime in particular, became almost taboo (Harries and Stadler, 1983).

Gradually, studies began emerging disproving the direct climate- crime linkage or including climatic variables with a host of other independent variables in causal analyses. An example of the former is a study by Lewis and Alford (1975) testing the Thermic Law of Delinquency by examining 3 years of monthly assault data across 56 US cities. Beginning with the winter months, the expectation was that the number of assaults would oscillate seasonally with the march of the sun on a south to north vector. Such an orderly progression was not found and, regardless of region, the transition from lower to higher levels of assaults was rather abrupt (Lewis and Alford, 1975). An example of the latter is a study by Van de Vliert et al. (1999) associating riots and armed attacks in 136 countries between 1948 and 1977 with temperature, population size and density, degree of democratic government, socioeconomic development, and a cultural masculinity dimension. They conclude that the culture mediates the effect between temperature and collective violence.

The fast pace of changes in computing and information systems technology since the mid-1980s has decreased the number of inquiries into the climate-crime relationship. Easy access to weather and crime information of varying temporal and spatial scales has spawned numerous studies on the relationship between crime or police activity with weather elements or events (see LeBeau and Corcoran, 1990; Rotton and Cohn, 2000). Despite the changes in focus the Thermic Law of Delinquency remains an integral guide for these and other studies.

The relationship between climate and crime is more suggestive than definitive, but climate is viewed as indirectly providing enhanced opportunities for the commission of different crimes. Finally, regardless of the empirical evidence, the public may feel there is a definitive relationship between the two; especially since many residential real-estate companies on their Internet websites list a range of factors describing the quality of life in a place and on the list climate is followed by crime.