JOHN TIERNEY IS MAKING SENSE!

No, I don't agree with him about the wacky theory that legalization of abortion was the leading cause of the big drop in crime a generation later, but I do give the house libertarian at The New York Times credit for rejecting more widely accepted varieties of mysticism regarding the crime drop:

The Miracle That Wasn't

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....

Then Tierney gets to Levitt's #1 reason -- abortion, which was legalized in New York a few years before Roe v. Wade. But never mind that.

The reason this Tierney column matters is that Rudy Giuliani is going to try to work his way back into politics (possibly in a bid for the White House) on the basis of two legends: the post-9/11 "America's Mayor" legend and the legend that he singlehandedly cleaned up Dodge, and did so with an idea, namely arresting the repulsive. This is powerful stuff -- a man of Good versus an evil enemy. It's tremendously appealing to a lot of voters.

I wouldn't have predicted that this legend would be rejected by the new conservative op-ed kid in Rudy's hometown, and I'm pleasantly shocked.

Tierney does give Giuliani some credit for the drop in crime, however:

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 what he's talking about here is prosaic. According to the legend, Giuliani wielded a moral Excalibur as squeegee men were driven from the streets and broken windows were fixed. The notion that that's why crime fell in New York City is a fairytale worthy of William Bennett's Book of Virtues. It's a crock, and I'm pleased that Tierney's a skeptic.