Top police officials and a prosecutor who played key roles in New York City’s crackdown on crime in the 1990s have taken their law enforcement skills to lead departments at Los Angeles, Miami, Providence, and Sarasota. During their tenure, all four cities have recorded decreases in crime beyond the national average.

The lawmen cut their teeth on the Compstat system of crime statistics and the quality-of-life style of policing at a time when New York was synonymous with urban blight. While the most recent FBI figures available show a nationwide slide of 2% in the crime rate in the first six months of 2004, the former New Yorkers have enjoyed significantly greater declines in their adopted cities.

In Los Angeles, a city that once captured headlines for riots and police brutality, felony crimes have fallen 18% since 2003, when a former commissioner of the New York Police Department, William Bratton, took over as top cop. Homicides there fell 20% in the past two years, to 515 in 2004 from 647 in 2002.

“I’ve predicted, with great confidence, that if we get 1,200 extra officers, we could get crime down another 50%,” Mr. Bratton said.

In New York, which currently has a 35,000-member police force, Mr. Bratton deployed armies of police officers to high-crime neighborhoods in the 1990s, creating a uniformed omnipresence. His policing philosophy is rooted in the “broken windows” concept pioneered by a Police Foundation sociologist, George Kelling of Rutgers University. It argues that a preponderance of quality-of-life crimes, such as vandalism and public drinking, creates fertile ground for more serious crimes, and cracking down on petty crime reduces violent crime. In Los Angeles, a city with half the population of New York but one-and-a-half times the geographical size, Mr. Bratton said his 9,000-member police force doesn’t have the manpower to saturate dangerous neighborhoods. He has relied instead on intensive use of police helicopters and canines to bring down crime. His referendum for 1,200 additional officers was shot down in October. He plans to put a similar referendum before voters in May, requesting a half cent increase in the sales tax to pay for the increase in officers.

“It’s not easy,” Mr. Bratton told The New York Sun. “They just don’t want to pay the money. But you get what you pay for.”

In Miami, crime dropped 8% last year with a former NYPD chief of departments and first deputy commissioner, John Timoney, as police chief. Mr. Timoney took over in January 2003, on the same day 13 police officers went on trial in federal court on charges in connection with shootings that were deemed questionable. Under Mr. Timoney’s leadership, the city went 20 months without an officer firing a single shot at a citizen.

“We train the officers to keep the fingers off the triggers,” Mr. Timoney, a former police chief of Philadelphia, said. “It’s kind of a turnaround from the general philosophy. These officers have clearly embraced the essential distinction between when an officer may shoot and when an officer must shoot.”

Mr. Timoney said he has provided his officers with Tasers, which are touted as a nonlethal way of subduing violent EDPs – police parlance for “emotionally disturbed persons.”

“This isn’t a criminal who sticks up a bodega or a liquor store,” Mr. Timoney said. “They’re not real criminals. They’re just crazy people.”

He shrugged off the controversy surrounding Tasers, which are maligned by some critics as deadly weapons.

“I’ve been Tasered three times, in front of television and everything,” the Miami chief said.

In Providence, felony crimes have fallen by 9% since a former Brooklyn assistant district attorney, Dean Esserman, became head of the police department in 2003, with violent crime plunging 18%. Mr. Esserman was appointed by a newly elected mayor, David Cicilline, who had defeated Vincent Cianci, the longtime mayor of the Rhode Island city, who is currently incarcerated for corruption. “It was a police department,” Mr. Esserman said, “that was freed from political and corrupt control and returned to the people.”

Mr. Esserman has also served as general counsel to New York City’s Transit Police, as police chief of Stamford, Conn., and as assistant police chief of New Haven. “We’ve had a dramatic decline in crime for two years in this city,” he said. “You’ll see the police department is regaining trust in this city.”

Mr. Esserman said he has “decentralized” his police department by establishing community offices in storefronts donated by individuals and businesses, and has provided Tasers to specially trained officers to deal with violent EDPs. Mr. Esserman described a recent situation in which officers responding to a domestic dispute were confronted by a knife wielding man, who slit his chest and ordered cops to shoot him. A responding lieutenant told the man, “We’re not shooting anyone here today,” and called in Taser-trained officers, who subdued the knife-wielding man, Mr. Esserman said.

In Sarasota, a coastal Florida city of 52,000 people, crime dropped 6.5% in 2003 and fell another 6% in 2004, the years after Chief Peter Abbott, a former Queens precinct commander who headed the NYPD’s mounted and administration units, became police chief. He has found that the Compstat system of identifying and addressing crime hot spots has been just as effective in a midsize city as it was in the Big Apple.

“It’s kind of like going fishing,” Mr. Abbott said. “You go where the fish are.”

Thieves troll the beaches, and tourists are not the most vigilant citizens, Mr. Abbott said. As a method of burglary prevention, officers patrol parking lots and check car doors, securing any that they find unlocked. “We’re just beating the crooks to the property,” the Sarasota chief said.

It’s not easy to tell whether policing is the prime cause in driving down crime, according to a consultant on criminal justice and security, Melvin Tucker, who is a former FBI agent and has served as police chief at Tallahassee, Fla., Morristown, Tenn., and two North Carolina cities, Asheville and Hickory.

“The police are not the sole influence on the crime rate in this country,” Mr. Tucker said. “It depends upon a successful prosecution of criminals. … It depends on the prison system. It depends upon accurate recordkeeping. Honestly, there have been efforts to tie crime reduction to job performance and even pay.”

Mr. Tucker said, however, that the decline in crime rates in cities headed by former New York crime-fighters is “something that other police chiefs should take recognition of and say, ‘If it’s working for him, why wouldn’t it work for me?’ “