The National Academy of Sciences will try to explain why crime rates change, political scientist James Q. Wilson, chair of the academy’s Committee on Law and Justice, writes in the Los Angeles Times. The study, Wilson says, will “try to sort out the combined and complex relations between crime and the economy, the age of the population, imprisonment, police work, neighborhood culture and gang activity.” Wilson notes that the Los Angeles Police Department reported that in 2008, for the sixth consecutive year, crime fell in the city. At a time when the economy was reeling and unemployment was rising, serious crime dropped about 2.5% over the previous year.
Scholars have made great progress in explaining why some individuals are more likely than others to commit crimes, but very little in explaining why the crime rate in a city or nation rises or falls, Wilson says. Because there is more crime in economically depressed inner-city neighborhoods than in affluent suburbs, many believe that if a community becomes more prosperous, crime rates will go down, and if income levels decline, crime rates go up. Economists who have checked this view have discovered that it is often true, but not always. They have found that the burglary rate goes up by 2 percentage points for every 1-point increase in the unemployment rate. That sounds like a big change until you realize that if the unemployment rate rises from 6% to 8% (about what it is in California now), the burglary rate will increase by 4%. Because burglaries aren’t measured very accurately (some are never reported, and police vary in how they report the statistics), it’s not certain that we would even notice so small an increase.