CHICAGO (AFP) -- France's zero-tolerance policy toward petty crime is unlikely to lead to a reduction in more serious crimes -- and instead could heighten tensions between police and the immigrant community, according to a recent U.S. study.

"It is dangerous," warned lead researcher and University of Chicago law professor Bernard Harcourt.

Harcourt's book "Illusion of Order: The False Promise of Broken-Windows Policing" was released in French last month with an updated introduction examining the repercussions of the November riots in France.

"Misdemeanor arrests can be expensive and the policy itself has been associated with increased complaints of police misconduct," Harcourt said. "You're squandering resources and it's also potentially combustible because of the relationship between the police and the communities that are being policed."

The zero-tolerance policy became popular following the publication of the "broken windows" theory in 1982, which argued that minor forms of disorder -- graffiti, litter, panhandling and prostitution -- will create an environment where crime becomes tolerated.

Fix the broken windows, and crime rates fall.

A simple concept that appeals to the basic human desire for order and security. But a concept which attacks the symptoms, not the cause, Harcourt found.

Then-New York mayor Rudy Giuliani implemented the theory when he took office in 1993 and credited a crackdown on panhandling, jaywalking, subway booth jumping and other misdemeanors with helping to reduce the overall crime rate.

Arrests for misdemeanors rose 50 percent while robberies fell 60.1 percent between 1993 and 1996.

But after carefully studying New York's crime data, Harcourt and colleague Jens Ludwig found that this was simply part of a national trend following the end of the crack cocaine epidemic.

Complaints about police misconduct in New York rose 68 percent during the same period. There were a number of controversial shooting deaths of unarmed suspects and a high-profile case involving a man beaten and sexually assaulted with a broomstick at a Brooklyn police precinct.

And those misdemeanor arrests were costly in terms of police time and prosecution costs: Harcourt estimates that New York's 190,000 misdemeanor arrests in 2004 cost 400 million dollars.

Yet the policy became popular, spreading to other U.S. cities and then overseas.

Hard-line French Interior Minister Nicolas Sarkozy began implementing a zero-tolerance policy towards petty crime in 2002, springing controversial raids on troublesome neighborhoods, clamping down on refugees and massively boosting police forces.

Friction quickly developed in the suburban zones largely populated by immigrant families, culminating in last November's three weeks of rioting that set the country ablaze following the accidental electrocution of two youths who hid in a power station while fleeing police.

Perhaps the most telling part of Harcourt's research was an examination of a program implemented in five major U.S. cities where about 4,600 low-income families living in high-crime public housing were given the chance to move to more "orderly" neighborhoods to escape the cycle of crime and violence.

Harcourt's analysis of arrest records and self-surveys three to five years later found no difference in criminal behavior between those who stayed in the neighborhoods filled with broken windows and those who left.

"The orderliness didn't rub off in the way we thought it would," he said.

Creating the outward appearance of order is important, Harcourt said, but dealing with social rather than criminal problems is not the best allocation of scarce police resources. And it also serves to criminalize social problems and an entire cohort of people already on the edge of society. "What this means in terms of practicality is that there should be more focused police targeting of serious crime," Harcourt said.

"If you have other issues that are quality of life issues find the right department: abandoned buildings, that's something for the housing department; turnstile jumping that's something for the transit authority."