While the details of Mr. Bratton’s role, including what kind of authority he would have, are just beginning to be negotiated, Mr. Bratton offered an overview of the kind of tactics that might be employed to quell any further unrest and to rebuild the police force’s reputation, which has been badly damaged in the wake of the newspaper scandal over the hacking of cellphone messages.
A focus of Mr. Cameron’s interest in him, Mr. Bratton said, is addressing how to take aim at the street gangs that law enforcement officials and others believe are playing a critical role in fomenting or engaging in the violence that began in north London a week ago and has led to hundreds of arrests and several deaths.
“What they are looking for, from me, is the idea of, what has been the American experience in dealing with the gang problem and, what has worked for us and not worked for us and how that can be applied,” Mr. Bratton said.
Mr. Bratton, a leading figure in urban crime-fighting tactics, is an advocate of so-called community policing, an approach grounded in the idea of flooding streets with officers who are immersed in people’s daily lives rather than using them simply to react or respond to specific events.
“You can’t just arrest your way out of the problem,” he said. “It’s going to require a lot of intervention and prevention strategies and techniques.”
Mr. Bratton, 63, who lives in New York City and is the chairman of Kroll, an international private security firm, began his career as a Boston police officer and went on to lead several police agencies that faced issues of corruption or excessive use of force.
He was New York City’s police commissioner for 27 months, from 1994 to 1996, and was credited with achieving record declines in crime before being forced out in a dramatic clash with Mayor Rudolph W. Giuliani.
Before that he had led Boston’s police force. Most recently, he was the chief of the Los Angeles police force, a position he held for nearly seven years, ending in November 2009.
Jeremy Travis, president of the John Jay College of Criminal Justice and a former director of the National Institute of Justice, said he was not surprised that Mr. Bratton had been tapped by British authorities.
“Bill Bratton is one of the leading figures in designing effective police responses to crime,” Mr. Travis said. “He is known for his successes in organizational turnaround and focusing organizations on their core mission of providing public safety and doing so in a way that protects the rights of the public.”
Mr. Bratton said he was reluctant to analyze the politics tied to the British turmoil or debate the performance of the law enforcement authorities in dealing with it. But the tension between a police force’s obligation to protect life and property, he said, and a society’s need to express itself freely is an inherent aspect of law enforcement.
What matters, he said, is legitimate and lawful policing, irrespective of the factors underlying any unrest. “The events of recent years have, in my mind, reinforced even more the importance of police in the society, to maintain order,” Mr. Bratton said, “whether against traditional crime or the new fears of terrorism or the fears of social disorder, like in London.”