Highly Selective Literature Review:
Crime rate measures the volume of crime on a per capita basis and is intended to adjust for population size so that comparisons can be made. It is well established that that the volume of crime is related to the size of a jurisdiction’s population. Thus, big cities typically have more crime than mid-size cities. However, the relationship between crime rate and population size is less clear. For example, big cities often have lower crime rates than mid-size cities. Basically, crime rate is useful as a standard of comparison across time and jurisdiction but it’s a crude and imperfect measure of public safety.- Establishing the statistical relationship between population size and UCR crime rate: Its impact and implications (2004) Nolan, J. J. Journal of Criminal Justice
Work commuters influence property crime, but add little to violent crime. However, recreational visitors are an important source of violent crime. Measures of daily population flows produce different crime rates maps than those based on simple residential population. Daily crime flows within a city (2015) Felson, M. & R. Boivin Crime Science .
A community’s crime rate may be higher than expected given its population if it has a lot of tourists (non-permanent residents). That’s because visitors can increase the number of crimes, but do not count in establishing the crime rate, which is based on how many people permanently reside there. How do you define crime rates in highly-touristed areas? (2017) Neighborhood Scout.
People spending more time outside the home, in public space, at night, and around potential offenders will have higher probabilities of victimization. - Human Mobility and Crime: Theoretical Approaches and Novel Data Collection Strategies (2021) Christopher R. Browning, Nicolo P. Pinchak, Catherine A. Calder Annual Review of Criminology
Data from the National Crime Victimization Survey revealed that the greatest risk of violent crime victimization occurs during travel between activities, such as walking to one’s car or waiting for the bus. - Risk of violent crime victimization during major daily activities (2012) Lemieux AM, Felson M. Violence and Victims
Crime rates based on residential population are a poor indicator of victimization risk in cities that attract a large daily population from outside the city limits. In these cities, the population at risk of crime includes inbound commuters to work. Commuters are typically victims of crimes committed by strangers, such as robbery or car theft, while residents are more likely to be victims of violent crimes committed by family and friends, such as homicide, rape and aggravated assault. The effect of commuting on city-level crime rates (2015) Stults, B. J., & Hasbrouck, M. Journal of Quantitative Criminology
Most calculations of crime rates are not estimates of crime risk because resident population is the denominator in these calculations and residents are not equally at risk. People at greater risk are residents or visitors who go to places favored by offenders, such as bars, hotels, or crowded streets. Cities with a large number of stay-at-home residents, such as retirees or remote workers, may have relatively low crime rates, because most crimes happen outside the home or in unoccupied homes (e.g., burglary). But that doesn’t mean the streets are safe. Crime Places in Crime Theory (2015) Eck, John & Weisburd, David L. Crime and Place: Crime Prevention Studies.
A Few Takeaways:
If the number of work commuters and tourists change little from year to year, a city’s crime rate based on residential population is still a pretty good indicator of crime trends.
If a city’s residents stay home more, the crime rate should go down. If they venture out into town more, it should go up (controlling for other factors, of course).
If a city normally attracts a large daily population from outside the city limits but the inflow of commuters and tourists suddenly plummets, its crime rate should also go down.
If significantly fewer residents visit high-crime areas in a city, the crime rate should go down.
If significantly more residents stay at home, fewer residents will be victims of street crimes.
If huge number of stores close, shouldn’t shoplifting go down?
Fewer potential targets = fewer crimes, assuming crime incentives and disincentives remain the same.
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