Kevin Drum writes a fascinating study in Mother Jones of how he use of lead, especially in gasoline is the real cause of crime in the world. This is important for many reasons but the most important being how we need to look beyond our own boundary of academic disciplines for understanding the causes of social issues.
Kevin goes through a host of explanations of the increase in crime and the decrease in crime in New York and other various cities in America. So, what explains what many would call the crime epidemic?
Experts often suggest that crime resembles an epidemic. But what kind? Karl Smith, a professor of public economics and government at the University of North Carolina-Chapel Hill, has a good rule of thumb for categorizing epidemics : If it spreads along lines of communication, he says, the cause is information. Think Bieber Fever. If it travels along major transportation routes, the cause is microbial. Think influenza. If it spreads out like a fan, the cause is an insect. Think malaria. But if it’s everywhere, all at once—as both the rise of crime in the ’60s and ’70s and the fall of crime in the ’90s seemed to be—the cause is a molecule.
A molecule? That sounds crazy. What molecule could be responsible for a steep and sudden decline in violent crime?
Well, here’s one possibility: Pb(CH2CH3)4.
Karl Smith’s explanation of epidemics is powerful if right. Something to explore in other contexts.
Lead studies have shown that lead exposure in small children is connected to a whole raft of complications later in life, including lower IQ, hyperactivity, behavioral problems, and learning disabilities. There is more evidence of juvenile delinquency and lead exposure.
So what about violent crime? Rick Nevin the consultant and research behind this found some intriguing evidence.
The biggest source of lead in the postwar era, it turns out, wasn’t paint. It was leaded gasoline. And if you chart the rise and fall of atmospheric lead caused by the rise and fall of leaded gasoline consumption, you get a pretty simple upside-down U: Lead emissions from tailpipes rose steadily from the early ’40s through the early ’70s, nearly quadrupling over that period. Then, as unleaded gasoline began to replace leaded gasoline, emissions plummeted.
Intriguingly, violent crime rates followed the same upside-down U pattern. The only thing different was the time period: Crime rates rose dramatically in the ’60s through the ’80s, and then began dropping steadily starting in the early ’90s. The two curves looked eerily identical, but were offset by about 20 years.
In a series of papers he concluded that he concluded that if you add a lag time of 23 years, lead emissions from automobiles explain 90 percent of the variation in violent crime in America.
What if we look at in different countries with different lead gasonline curves?
Nevin collected lead data and crime data for Australia and found a close match. Ditto for Canada. And Great Britain and Finland and France and Italy and New Zealand and West Germany. Every time, the two curves fit each other astonishingly well. When I spoke to Nevin about this, I asked him if he had ever found a country that didn’t fit the theory. “No,” he replied. “Not one.”
More research into lead shows more evidence of issues that create violent behaviour.
So lead is a double whammy: It impairs specific parts of the brain responsible for executive functions and it impairs the communication channels between these parts of the brain. For children like the ones in the Cincinnati study, who were mostly inner-city kids with plenty of strikes against them already, lead exposure was, in Cecil’s words, an “additional kick in the gut.” And one more thing: Although both sexes are affected by lead, the neurological impact turns out to be greater among boys than girls.
The article is well research and shows an enormous amount of evidence that shows the connection of lead exposure to crime. Lead continues to effect us through its presence in soil.
So why did most criminologists miss this? Why did the theories that explain crime does not take lead into account?
First, is the “man with a hammer problem”.
Why not? Mark Kleiman , a public policy professor at the University of California-Los Angeles who has studied promising methods of controlling crime, suggests that because criminologists are basically sociologists, they look for sociological explanations, not medical ones.
Politics plays a second role.
My own sense is that interest groups probably play a crucial role: Political conservatives want to blame the social upheaval of the ’60s for the rise in crime that followed. Police unions have reasons for crediting its decline to an increase in the number of cops. Prison guards like the idea that increased incarceration is the answer. Drug warriors want the story to be about drug policy. If the actual answer turns out to be lead poisoning, they all lose a big pillar of support for their pet issue. And while lead abatement could be big business for contractors and builders, for some reason their trade groups have never taken it seriously.
The benefit-cost analysis is absolute in terms of the the magnitude of benefits.
This article raises a number of questions for me and in fact, teaches a few things. What is intriguing is what’s happening because of this?
For example, what is Australia’s public policy saying about it? What are the associated issues? Can we use similar analysis to understand the increased child protection challenges Australia faces? Is this connected to lead exposure? What about the “aboriginal children” epidemic in child protection and juvenile justice?