Here’s a chart depicting the drop in crime rates in the U.S. in recent years:
Quite striking, isn’t it? The drop of the last few years is especially interesting, since usually crime rates spike during recessions.
Lots of theories have been proposed to explain the drop over the last two decades. Here’s an interesting one: A researcher from Amherst College has looked at childhood lead exposure rates and crime rates — making use of the fact that different states have different lead exposure histories — and concluded that phasing out leaded gasoline was responsible for a 56% decline in violent crime from 1992 to 2002.
How? Leaded gasoline was the main source of lead exposure from the 1950s through the 1970s, 90% of children in the 70s had lead levels in their blood that would cause concern today, even minute childhood exposure is linked to aggressive and violent behaviour, but in 1974 the EPA mandated a timetable for the removal of lead from gasoline. The result? A 99% reduction in gasoline lead exposure by 1990.
Why did the crime rates only go down in the 1990s if the phasing out of leaded gasoline started in the 1970s? Because toddlers aren’t the ones committing crimes, even if they’ve been poisoned by lead. Rather, 20-year-olds who were exposed as young children commit the crimes. Hence the lag time. (If you have the appropriate institutional arrangements, you can read more here.)
Oh, and by the way, we already knew about the dangers of lead in gasoline back when it was introduced in the 1920s. But oil companies decided profits were more important.
I’ll leave you with a closing quotation from one of the esteemed presidential candidates of the United States of America, Michelle Bachmann: “What we need to do is pass the mother of all repeal bills … And I would begin with the EPA, because there is no other agency like the EPA. It should really be renamed the job-killing organization of America.”