Excerpt from Freakonomics by Steven Levitt, Stephen J. Dubner, plus links to reviews, author biography & more

Introduction:
The Hidden Side of Everything

Anyone living in the United States in the early 1990s and paying even a whisper of attention to the nightly news or a daily paper could be forgiven for having been scared out of his skin.

The culprit was crime. It had been rising relentlessly -- a graph plotting the crime rate in any American city over recent decades looked like a ski slope in profile -- and it seemed now to herald the end of the world as we knew it. Death by gunfire, intentional and otherwise, had become commonplace. So too had carjacking and crack dealing, robbery and rape. Violent crime was a gruesome, constant companion. And things were about to get even worse. Much worse. All the experts were saying so.

The cause was the so-called superpredator. For a time, he was everywhere. Glowering from the cover of newsweeklies. Swaggering his way through foot thick government reports. He was a scrawny, big city teenager with a cheap gun in his hand and nothing in his heart but ruthlessness. There were thousands out there just like him, we were told, a generation of killers about to hurl the country into deepest chaos. In 1995 the criminologist James Alan Fox wrote a report for the U.S. attorney general that grimly detailed the coming spike in murders by teenagers. Fox proposed optimistic and pessimistic scenarios. In the optimistic scenario, he believed, the rate of teen homicides would rise another 15 percent over the next decade; in the pessimistic scenario, it would more than double. "The next crime wave will get so bad," he said, "that it will make 1995 look like the good old days." Other criminologists, political scientists, and similarly learned forecasters laid out the same horrible future, as did President Clinton. "We know we've got about six years to turn this juvenile crime thing around," Clinton said, "or our country is going to be living with chaos. And my successors will not be giving speeches about the wonderful opportunities of the global economy; they'll be trying to keep body and soul together for people on the streets of these cities." The smart money was plainly on the criminals.

And then, instead of going up and up, crime began to fall. And fall and fall and fall some more. The crime drop was startling in several respects. It was ubiquitous, with every category of crime falling in every part of the country. It was persistent, with incremental decreases year after year. And it was entirely unanticipated -- especially by the very experts who had been predicting the opposite.

The magnitude of the reversal was astounding. The teenage murder rate, instead of rising 100 percent or even 15 percent as James Alan Fox had warned, fell more than 50 percent within five years. By 2000 the overall murder rate in the United States had dropped to its lowest level in thirty-five years. So had the rate of just about every other sort of crime, from assault to car theft.

Even though the experts had failed to anticipate the crime drop -- which was in fact well under way even as they made their horrifying predictions -- they now hurried to explain it. Most of their theories sounded perfectly logical. It was the roaring 1990s economy, they said, that helped turn back crime. It was the proliferation of gun control laws, they said. It was the sort of innovative policing strategies put into place in New York City, where murders fell from 2245 in 1990 to 596 in 2003.

These theories were not only logical; they were also encouraging, for they attributed the crime drop to specific and recent human initiatives. If it was gun control and clever police strategies and better paying jobs that quelled crime -- well then, the power to stop criminals had been within our reach all along. As it would be the next time, God forbid, that crime got so bad.

The foregoing is excerpted from Freakonomics by Steven D. Levitt and Stephen J. Dubner. All rights reserved. No part of this book may be used or reproduced without written permission from HarperCollins Publishers, 10 East 53rd Street, New York, NY 10022