This blog is a part of our series, “Perspectives in Crime” where we explore leading academic studies that touch on crime data.
For many years, deciphering the rhythm of crime was a complex task. Crime was viewed as sporadic, random, and driven solely by opportunity or desperation. The recent surge in the availability of crime data, however, has revealed patterns and insights into the temporal patterns of criminal behavior.
Much of modern criminology builds off routine activities theory, a concept established in the late 1970s by sociologists Lawrence E. Cohen and Marcus Felson. Simply stated, it proposes that crime occurs at the intersection of three factors: a suitable target, a motivated offender, and a lack of capable guardianship.
Another longstanding idea is crime seasonality, an idea even older than routine activities theory, first posited in 1913 by Adolphe Quetelet, a Belgian statistician. Crime seasonality observes that many cities, cultures, and societies experience increased crime during the summer months.
This yearly rhythm of crime, and what mechanisms produce these seasonal changes, has been a subject of debate. Originally theorists believed significant upswings in crime during summer months were caused by changes in weather. There is now a growing consensus that changes in routine, larger public gatherings, and other societal behaviors contribute to more opportunities for crime during the summer months. This is the routine activities theory understanding of crime seasonality.
Modern crime data provide an increasingly granular understanding of crime, allowing patterns to be better highlighted and analyzed. Beyond the patterns of crime across seasons, there are clear patterns for crime risk that unfold every week. Most types of crime exhibit unique signatures across the 24-hour cycle as well as the seven-day week. Understanding these patterns can help anticipate the fluid nature of crime risk and provide insight into the meaningful allocation of security resources.
Does guardianship affect burglary rates?
Looking at the last five years of crime data from the Denver Police Agency, incidents of burglary occur more frequently during the traditional working week as opposed to the weekend.
Through the lens of routine activities theory, this is likely driven by changes in guardianship throughout the week. Many homes are empty during the workday as compared to the weekend. Offenders knowing that they are least likely to encounter guardianship in the home during work hours and school days might target this period when committing a burglary. Additionally, late night hours when people are asleep have a higher number of incidents as compared to early morning, when many households are getting ready for work or school.
The below charts show the average weekly counts of burglary incidents by time of day and day of the week between 2018-2023.
Average weekly counts of burglary incidents by time of day and day of week, 2018-2023.
Weekday vs. weekend
Daytime vs. night
Frequency of assault rates
Denver’s crime data shows that violent interpersonal crimes occur more frequently during the weekend, in particular peaking late Friday night (Saturday morning) and late Saturday night (Sunday morning).
During the work week, aggravated assaults in Denver also peak in the late evening, however, this peak occurs slightly earlier compared to the weekend. This is likely driven by behavior and societal norms, in which people are going to sleep earlier during the work week. Additionally, aggravated assaults occur most frequently in places of residence, suggesting situations involving alcohol and domestic violence. The increased incidents of aggravated assault on the weekend might reflect the additional number of assaults that occur in public and downtown areas with the increased traffic to bars and events.
The below charts show the average weekly counts of aggravated assault incidents by time of day and day of the week between 2018-2023.
Average weekly counts of aggravated assault incidents by time of day and day of week, 2018-2023.
Weekday vs. weekend
Daytime vs. night
The frequency and type of crime in your community can have a profound impact on your organization’s bottom line. Crime risk is closely correlated with property values, school enrollment, and a wide range of municipal outcomes. The Pinkerton Crime Index (PCI) can help businesses determine security needs and intelligently allocate resources, perform comprehensive site risk assessments, standardize smart risk and security protocols, inform proactive investment decisions, and fulfill compliance obligations — from regulatory and insurance requirements to duty of care responsibilities. Connect with us to find out how PCI can help you.
