Bad moon on the rise? Lunar cycles and incidents of crime

Abstract

a b s t r a c tPopular cultures in Western societies have long espoused the notion that phases of the moon influence human behavior. In particular, there is a common belief the full moon increases incidents of aberrant, deviant, and criminal behavior. Using police, astronomical, and weather data from a major southwestern American city, this study assessed whether lunar cycles related with rates of reported crime. The findings fail to support popular lore, which has suggested that lunar phase influenced the volume of crime reported to the police. Future research directions examining qualitative rather than quantitative aspects of this problem may yield further inform the understanding of whether lunar cycles appreciably influence demands for policing services.

Rescue responses during a full moon and Friday 13th

“…Foster and Roenneberg (2008) in their review paper cited 45 studies that found no consistent relationship between lunar influence and psychosis, depression, anxiety, violent behaviour, aggression, seizures, suicides, absenteeism rates, coronary failure, conception, birth, menstruation, surgery and survival of breast cancer, post-operative outcome, renal colic, outpatient admissions and automobile accidents. Schafer et al (2010) cited several additional studies in which no lunar effect was found on prison escapes, hospital admissions for dog bites, hockey player aggression and homicide. Margot (2015) showed that the few studies that found a relationship between the phase of the moon and the studied effect have typically made one of the following errors: small sample size, short period of study, lack of control for holidays or day of the week, cycle of the moon sampling procedure or statistical testing.…”

A Hunter’s Moon: the Effect of Moon Illumination on Outdoor Crime

“…Because of the difficulty in obtaining data calibrated in daily or hourly intervals, prior research analyzed data drawn from a single geographical location (Núñez et al, 2002;Schafer et al, 2010). These types of samples are problematic because they tend to be unrepresentative thereby making generalizability of results difficult.…”

“…Thus, it is not necessary to include in the outdoor crime equation tangentially related control variables such as the amount of precipitation in a 24-h period, temperature, or weekend (see Schafer et al, 2010). These commonly used control variables are problematic because they tend to be vitiated with measurement error.…”

“…Police officers may also be more visible during a full moon, thus causing a potential offender to decide against committing a crime. As Cozens, Saville and Hillier (2005:331) note, BIf offenders perceive that they can be observed (even if they are not), they may be less likely to offend, given the increased potential for intervention, apprehension and prosecution.F inally, recent research evinces little evidence of a substantive relationship between the amount of natural light generated by the different phases of the moon and criminal activity (Núñez, Pérez Méndez, and Aguirre-Jaime, 2002;Schafer, Varano, Jarvis, and Cancino, 2010). It is often argued that the causal processes theorized to be responsible for a relationship between moon illumination and crime are tenuous at best when one considers that a 100-watt light bulb generates about 70 times the luminance of a full moon (Bennett, 1977).…”

The Moon’s Contribution to Nighttime Illuminance in Different Environments

“…However, the researchers did not control for variables that may influence the frequency of fatalities, e.g., temperature, day of week, precipitation, cloudy sky, etc. Other research generally provides unreliable evidence for the effect of lunar phase on reported crime and disorderly conduct (e.g., Núñez et al, 2002;Schafer et al, 2010). At least in terms of aggression or crime at nighttime, changes in the moon's illuminance do not generally support the opinion that as more light is reflected by the moon, visibility and deviant behavior increases.…”