Serial homicide offenders and the lunar cycle

Area of Science:

• Criminology
• Forensic Psychology
• Astrophysics

Background:

• Media fascination with serial homicide offenders (SHOs) and lunar cycles perpetuates myths.
• Previous research lacks robust statistical analysis on the lunar cycle's influence on criminal activity.

Purpose of the Study:

• To statistically determine if lunar cycles correlate with the predatory activation of serial homicide offenders.
• To investigate the influence of Moon phase, distance, and illumination on homicide frequency.

Main Methods:

• Utilized a quasi-Poisson log-linear regression model.
• Analyzed 9976 homicides recorded between January 1, 1960, and November 30, 2016.
• Examined lunar phase, Moon's distance from Earth, seasonal variation, and illuminated surface percentage.

Main Results:

• Lunar phase showed no statistically significant influence on homicide frequency (p = 0.997).
• Rate ratios across Moon phases were narrowly distributed around 1.00.
• Moon's distance, seasonal variation, and illuminated surface were not significant predictors.
• Victim age (15-64) was a significant factor (p < 2e-16).

Conclusions:

• No statistical evidence supports a relationship between lunar cycles and serial homicide offender activity.
• Findings are based on a large sample size and extended 56-year observation period.
• Debunks the myth of lunar influence on criminal behavior in serial homicide.