In one of his many fine recent columns on crime, Times-Picayune columnist Jarvis DeBerry wrote (my emphases):

[New Orleans Police Superintendent Ronal] Serpas and his predecessor have both struggled to explain why things are particularly bad here. [Former Superintendent] Warren Riley wondered if there isn’t something in the water. Serpas hasn’t said anything so bizarre, but he likes to cite a federal report that says our homicides are different, that they are more likely to grow out of arguments between acquaintances than they are in other places.

Here’s two quick thoughts on that passage, which I’ll sketch briefly and then explain at length, in reverse order. By the end we’ll have solved the crime problem.

1) Perhaps Riley’s suggestion that there is “something in the water” wasn’t so bizarre. Let’s take his claim metaphorically,  rather than literally. Maybe he was saying that there are unknown public health factors that contribute to crime here, rather than specific crime-inducing pollutants in our tap water. Perhaps there are pollutants on our windowsills and in our playground soils that are highly associated with crime. And perhaps these pollutants contribute to our “unnaturally” high homicide rate as well as the type of homicides we are more likely to suffer here.

2) Everyone “struggles to explain” why the New Orleans streets are so lethal. But our local “murder mystery” is part of a much larger one. Crime rates have plummeted throughout the nation over the past 20 years, but no one can explain that trend, either. Don’t we have to understand the national movement toward less crime before we can explain why New Orleans isn’t part of it?

We forget that 20 years ago, violent crime was a major national issue. Conservative pundits noted that crime had risen markedly since the late 1960s, about the time American culture went to pot (in their view). The era’s moral relativism had led to more working mothers, undisciplined fathers, latch-key kids, drug-fried brains, welfare dependency and broken cities. Suburban teens tried gateway drugs and listened to nihilistic heavy metal on their Sony Walkmans, while urban males were recruited by crack-dealing gangs who blasted equally nihilistic rap from boom boxes.  Coarsened values (divorce, abortion) plus soft justice (prison furloughs, too little capital punishment) made for a dangerous brew.

Twenty years ago, these cultural worries were buttressed with “alarming” demographic prognostications. Minority neighborhoods had higher crime and higher birth rates. Ergo, much of the country felt it was “doomed” to become bloodier as it became browner. (Though the political-correctness police forbade “honest” discussion of these troublesome trends.) So if you thought crime was bad in 1992 (like most did), the trend lines indicated it would only worsen.

To everyone’s considerable relief, this cranky view of America’s cultural trajectory turned out to be wildly wrong. During the next 20 years, homicide rates in most cities plummeted like a lead brick.

The statistics are mind-blowing. True, homicide rates rose in the late ’60’s and early ’70’s and remained elevated through the early ’90’s. The U.S. homicide rate was identical in 1974, 1981 and 1991– 9.8 per 100,000 U.S. inhabitants — with little variation in-between. But then, in 1994, the national rate began a sustained drop. By 2000, per capita homicides had fallen to their lowest level in 35 years (5.5 per 100,000 people) and remained low through 9/11, Iraq, Katrina, and The Great Recession (2007-2009). Even as unemployment doubled, the rate continued to fall, all the way down to 4.8 homicides per 100,000 in 2010. Preliminary F.B.I. reports suggest that violent crime dropped again in 2011. Today, in many cities, homicides are down to levels not seen since the ”halcyon” 1950’s.

Put another way: there were at least 56 million more people in the U.S. in 2010 than in 1991 (including many millions of illegal immigrants), yet there were 10,000 fewer total homicides (14,748 versus 24,700). That’s amazing.

The dramatic, sustained decrease in crime is one of the most important unsung stories of the past 20 years. Reduced crime has undoubtedly boosted our national economy by hundreds of billions of dollars. And a whole generation has grown up without any sense of “crime wave” hysteria. Candidates for national office hardly even debate the topic anymore.

What a wonderfully safe time to be alive, right?

Yay.

Unfortunately, New Orleans hasn’t shared in the national good fortune. Our city remains a tragic outlier from the broad trend toward less violent crime. The homicide rate remains very high here, while nearly everywhere else it’s on the wane.

As DeBerry noted in his column, New Orleans did see progress in the 1990’s, when homicide rates were cut in half.  But that drop was from apocalyptic  levels (86 per 100,000 New Orleanians in 1994) down to a merely horrendous rate (still 7.5 times the national average). And even those improvements were fleeting. The slaughter  steadily increased in the years before the Federal Flood in 2005, and then quickly returned to high levels as the city repopulated.  Last year, homicides rose in the Crescent City to 58 per 100,000, while they dropped in most other urban areas– even in cities with much higher unemployment. Killings in New Orleans have spiked even higher in recent months, and everyone is on edge. Even if things “stabilize” around here, this tourist-driven town will still seem increasingly dangerous compared to its ever-safer host country.

Local leaders have pantingly demonstrated their concern, of course. We’ve seen a nauseatingly familiar flurry of activity: legislators have militated for the National Guard to return. City Council members enacted a curfew for teens in the French Quarter. City Hall suggested higher bonds for violent gun offenders. The NOPD is set to try the “Milwaukee model” of crime fighting. Young people have rallied around the #nolalove hashtag to maintain hope. There have been neighborhood meetings, demonstrations, speeches, task forces, summits, outrage, grief, prayer, frustration … Perhaps the “Thou Shalt Not Kill” billboards of the 1990’s will soon be resurrected. One gets the feeling that protests and calls for resignations are not far off.

Mayor Mitch Landrieu claims we need to fight the “culture of death” in the city by attacking the “root cause” of crime. Accordingly, he plans to “fight the crime surge with an emphasis on mental health, education and employment, as well as more patrols and targeting hotspots.” This fits in with Landrieu’s “let’s solve all the problems at once” approach. Still, that’s a lot of long-term “roots” to tackle at once.

And do we truly know what the roots of crime actually are?

We sure act like we do. Everyone has strong opinions about crime reduction in New Orleans. But nobody can tell a persuasive, comprehensive story explaining why homicide rates have plummeted nationally. We don’t really know. Sure, crime fell in Milwaukee, but it also fell in a hundred other cities that used different approaches.

That’s what makes the national trend so interesting. It flouts our old theories about the causes of crime, and it confounds our (caricatured) cultural narratives of the past forty years. Let’s be open to the idea that we know much less than we think we know about the causes of crime, both nationally and here in New Orleans.

In a Wall Street Journal piece titled “Why Crime Keeps Falling,” noted political scientist James Q. Wilson evaluated the main explanations for the national crime drop since the early ’90’s. Does low unemployment explain the crime reduction?  Wilson says no. What about high incarceration rates? No. Better police strategies? Maybe. The large shift in drug use from cocaine to marijuana? Maybe.

Then Wilson refers to a very intriguing “medical explanation” for the reduction in crime, only to give it short shrift and end his peroration by tossing a chunk of read meat to culture warriors  who share his right-wing views:

At the deepest level, many of these shifts, taken together, suggest that crime in the United States is falling… because of a big improvement in the culture. The cultural argument may strike some as vague, but writers have relied on it in the past to explain both the Great Depression’s fall in crime and the explosion of crime during the sixties. In the first period, on this view, people took self-control seriously; in the second, self-expression—at society’s cost—became more prevalent. It is a plausible case.

While I understand Wilson’s desire to give a conservative explanation for the national crime mystery, this vague pap about cultural improvement just doesn’t wash. Not even Wilson’s  fellow travelers will buy into the idea that American culture suddenly shifted towards “self-control” during the Clinton years. And if it did, where was this control during the dotcom and housing bubbles, two of the most fevered market manias in recent history?

Tattoos and blogs are ubiquitous, savings rates are low and skivvies-revealing trousers even lower. Yet, after weighing the evidence, Wilson contends our culture has turned away from “expression” and towards responsibility. He says it has shown a “big improvement.” That’s his explanation for the dramatic crime reduction during the years from Kato Kaelin to Snooki. So let’s take another look at thought No. 1 mentioned at the beginning of this post: the “medical” explanation Wilson mentions so glancingly. Here’s what he wrote:

A 2007 study by the economist Jessica Wolpaw Reyes contended that the reduction in gasoline lead produced more than half of the decline in violent crime during the 1990s in the U.S. and might bring about greater declines in the future. Another economist, Rick Nevin, has made the same argument for other nations.

A tantalizing theory that might explain “over half the decline in violent crime” has generated remarkably little ink. A 2007 Washington Post piece was an exception:

The theory offered by the economist, Rick Nevin, is that lead poisoning accounts for much of the variation in violent crime in the United States. It offers a unifying new neurochemical theory for fluctuations in the crime rate, and it is based on studies linking children’s exposure to lead with violent behavior later in their lives.

What makes Nevin’s work persuasive is that he has shown an identical, decades-long association between lead poisoning and crime rates in nine countries.

“It is stunning how strong the association is,” Nevin said in an interview. “Sixty-five to 90 percent or more of the substantial variation in violent crime in all these countries was explained by lead.”

Through much of the 20th century, lead in U.S. paint and gasoline fumes poisoned toddlers as they put contaminated hands in their mouths. The consequences on crime, Nevin found, occurred when poisoning victims became adolescents. Nevin does not say that lead is the only factor behind crime, but he says it is the biggest factor.

Correlation is not causation, of course, but the research linking lead to violent crime is deeply intriguing. Perhaps lead poisoning is a major contributor to New Orleans’ stubbornly high homicide rate.

Lead is a neurotoxin that poses serious health risks, especially to children. Lead can permanently impair cognition and damage the nervous system. But lead exposure is also linked to behavior problems, namely impulse control. That seems to be  in line with the federal study which noted that more homicides in New Orleans arise out of “heat of the moment” arguments than in other places. The idea that high lead exposure in childhood reveals itself in reduced impulse control later on has intuitive appeal.

We already know that there are elevated lead levels in New Orleans. According to a 2007 study:

Before Katrina, over 50 percent of children living in the inner city neighborhoods of New Orleans (disproportionately neighborhoods of color) had blood lead levels above the current guideline of 10 micrograms per deciliter. Childhood lead poisoning in some of New Orleans black neighborhoods was high as 67 percent.

Last year, the city closed three playgrounds due to lead levels, and remediated eight more. And we know there are tens of thousands of old houses here, many blighted, that contain lead paint. When the outer coats of safe paint rub off, lead dust collects on the house and ground. Old wooden windows rub off layers of paint, and sometimes dust windowsills with lead that our children touch (and ingest).

Other research indicates that lead in the soil is a better predictor lead poisoning than neighborhoods with old houses. The idea is that residues from lead gasoline emissions contaminated soils over time, mostly in heavily-trafficked city-centers.  Children play in this soil, and become poisoned.

As the nation removed lead from gasoline, paint and household products, starting in the 1970’s, there was tremendous improvement in children’s blood lead levels. And by the mid-1990’s, crime rates were cratering.

Unfortunately, a lot of inner cities still have high residual lead concentrations. One study claimed that “the quantity of lead in New Orleans inner-city soils is about the same as that of the lead-smelter community of Trail, [British Columbia, site of the largest zinc-lead smelter in North America].” And unlike the cities in the rust belt and the Northeast, the climate here allows for year-round access and exposure to contaminated soils.

I know the lead-crime theory is a “liberal” notion. It doesn’t push our buttons about free will and retributive justice. It doesn’t appeal to our basic assumptions about the “roots” of crime. We’d prefer to blame bad parents rather than toxins in the environment. We’d like to think our children are being neglected by their parents, not poisoned. Remember though, if we want to blame the parents in New Orleans for their criminal offspring, then we have to credit the national drop in crime to a widespread case of good parenting everywhere else. (Gotcha!)

Lead removal may be expensive, but there are already a ton of good public health reasons to reduce our exposure. There’s growing evidence linking blood-lead levels and cognitive development, a factor in employability. And if there really is a strong connection between lead and crime, as economists like Nevin claim, then reducing our children’s exposure to lead will pay for itself very quickly. (Unfortunately, Congress recently cut funding for lead prevention programs.) Clearly, we shouldn’t halt our other initiatives to reduce violent crime in New Orleans. But let’s also learn more about its correlation with lead exposure. At minimum it  demands more attention; it might even explain the puzzling drop in national crime at a time when the New Orleans homicide rate remains stubbornly high.

So let’s test our children, as well the soils they play in. Perhaps if we get the lead out of their blood, 20 years from now there will be less hot lead flying about our bloody streets.

Thanks to Editor B., whose posts about his daughter’s blood-lead levels moved and informed me.