From today's New York Times:
The Miracle That Wasn't
By JOHN TIERNEY
Published: April 16, 2005
It is an inspirational urban lesson from the 1990's: take back the streets from squeegee men and drug dealers, and violent crime will plummet. But on Thursday evening, the tipping-point theory was looking pretty wobbly itself.
The occasion was a debate in Manhattan before an audience thrilled to be present for a historic occasion: the first showdown between two social-science wonks with books that were ranked second and third on Amazon.com (outsold only by "Harry Potter"). It pitted Malcolm Gladwell, author of "Blink" and "The Tipping Point," against Steven D. Levitt, an economist at the University of Chicago with the new second-place book, "Freakonomics."
Professor Levitt considers the New York crime story to be an urban legend. Yes, he acknowledges, there are tipping points when people suddenly start acting differently, but why did crime drop in so many other cities that weren't using New York's policing techniques? His new book, written with Stephen J. Dubner, concludes that one big reason was simply the longer prison sentences that kept criminals off the streets of New York and other cities.
The prison terms don't explain why crime fell sooner and more sharply in New York than elsewhere, but Professor Levitt accounts for that, too. One reason he cites is that the crack epidemic eased earlier in New York than in other cities. Another, more important, reason is that New York added lots of cops in the early 90's.
But the single most important cause, he says, was an event two decades earlier: the legalization of abortion in New York State in 1970, three years before it was legalized nationally by the Supreme Court.
The result, he maintains, was a huge reduction in the number of children who would have been at greater than average risk of becoming criminals during the 1990's. Growing up as an unwanted child is itself a risk factor, he says, and the women who had abortions were disproportionately likely to be unmarried teenagers with low incomes and poor education - factors that also increase the risk.
It's a theory that doesn't sit well with either liberals or conservatives, and Professor Levitt hastens to add that the reduction in crime is not an argument for encouraging abortion - he personally has mixed feelings on whether abortion should be legal. But he says the correlations are clear: crime declined earlier in the states that had legalized abortion before Roe v. Wade, and it declined more in places with high abortion rates, like New York.
Some criminologists have quarreled with his statistics, but the theory was looking robust at the end of the debate in Manhattan. Mr. Gladwell, while raising what he called a few minor quibbles, seemed mostly persuaded by the numbers.
"My first inclination," he joked at the beginning of his rebuttal, "is to say that everything you just heard from Steven Levitt, even though it contradicts things I have written, is true."
That's my inclination, too, as a less successful exponent of the same theory. (In 1995 I explained the crime decline with my version of the tipping point, the Squeegee Watershed, which became neither a buzzword nor a best seller.) In retrospect, the New York crime story looks like a classic bit of conventional wisdom, as the term was originally defined by John Kenneth Galbraith: an idea that becomes commonly accepted because it is "what the community as a whole or particular audiences find acceptable."
Unlike the abortion theory, which was raised in the 1990's and angrily dismissed, the tipping-point idea jibed reassuringly with everyone's beliefs and needs. Urbanites and politicians welcomed a new reason to crack down on street nuisances. Journalists wanted a saga with heroes. Criminologists and the police loved to see their new strategies having dramatic results.
I still think the police made some difference, and not merely because there were more of them on the streets. The new computerized crime-tracking strategies put new pressure on them.
One veteran cop told me that traditionally only a quarter of the officers had done their jobs, and that the heroic achievement of Commissioner William Bratton and Mayor Rudolph Giuliani had been to get that figure up to 50 percent.
But it now looks as if the good guys did not take back the streets all on their own, and the moral of the story is less about safe streets than safe beliefs. Professor Levitt's abortion theory is not appealing. But the ideas that make us comfortable are the ones to beware.
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I have nothing to add; it's what I've been saying all along with regard to low-income women with poor educations raising unwanted children.