Dec. 5, 2013: William Bratton, left, displays a book he claims influenced his policing from a young age as New York Mayor-elect Bill de Blasio looks on during a news conference in New York. Bratton, whose tenure as New York City police commissioner in the 1990s was marked by a steep decline in crime and clashes with then-Mayor Rudolph Giuliani, has been chosen to lead the nation's largest police force again. De Blasio announced the appointment Thursday, saying Bratton is a 'proven crime-fighter' who knows how to keep the city safe. (AP/Seth Wenig)