William Joseph "Bill" Bratton CBE (born October 6, 1947) is an American law enforcement officer who served as the chief of police of the Los Angeles Police Department (LAPD), New York City Police Commissioner, and Boston Police Commissioner.
Bratton began his police career at Boston Police Department before becoming Police Commissioner in New York City, where his zero-tolerance policy has been credited with reducing petty and violent crime. He moved to Los Angeles Police Department in 2001 reforming the police after the 1992 Los Angeles Riots and crime was reduced.
Bratton's policing style is influenced by the broken windows theory that if minor, petty crime is not dealt with, crime will increase. He advocates having an ethnically diverse police force representative of the population, maintaining a strong relationship with the law-abiding population, tackling police corruption, being tough on gangs and a strict no-tolerance anti-social behaviour.