(Adds news conference quotes, reaction from governor, ACLU)
By Chris Francescani
NEW YORK, Dec 5 (Reuters) - Bill Bratton, a veteran police chief who has led departments across the country, was named on Thursday as New York City's next police commissioner, taking over a force credited with a sharp drop in violent crime but criticized for its tactics.
Bratton, 66, who was police commissioner under New York City Mayor Rudy Giuliani and has run police departments in Los Angeles and Boston, will return to the NYPD on Jan. 1, taking over from Ray Kelly.
Kelly, serving under outgoing Mayor Michael Bloomberg, has overseen the city's security in the years after the Sept. 11, 2001, attacks and the historic, a drop in murders and violent crime over two decades.
Calling Bratton a "progressive visionary" and a "proven crime-fighter," New York City Mayor-elect Bill de Blasio pledged to preserve and deepen the city's historic reduction in violent crime while protecting the civil rights of New Yorkers.
"The fact is that over an extraordinary career, Bill Bratton has proven that you can fight crime effectively and bring police and community together," de Blasio said as Bratton stood at his side.
In an August ruling that found the Kelly-era police tactic of stop-and-frisk amounted to indirect racial profiling, a federal judge ordered the city to submit to an independent monitor.
Stepping to the podium at the Red Hook Criminal Justice Center in Brooklyn, Bratton promised to keep crime down and remain on guard against threats of terror while bridging the growing gap between police and minority communities.
"I will get it right in this city," Bratton said. "If we get it right here, this can in many ways be a beacon that lights the rest of the world."
With the appointment, Bratton, who served as commissioner from 1994 to 1996, and Kelly, who previously held the job from 1992 to 1994, are the only two commissioners in NYPD history to serve two tenures at the helm of the nation's largest police force.
Bratton was first appointed NYPD commissioner by Giuliani in 1994. In his first two years, the city's murder rate fell nearly 40 percent.
His signature achievement came in 1995, with the introduction of CompStat, a police performance management system that tracks and analyzes real-time crime data to hold precinct commanders accountable. On Thursday, de Blasio described the program as the game changer in the city's approach to crime.
CompStat soon spread to major police departments across the country. But Giuliani and Bratton clashed frequently, and the commissioner resigned in 1996.
Starting in 2002, as chief of the Los Angeles Police Department, Bratton worked with both an inspector general and a federal monitor, instituted in the wake of a bruising late-1990s corruption scandal.
Kelly's tenure began less than four months after the Sept. 11. attacks, and under his direction the city created a global counter-terrorism unit and stationed NYPD investigators in 11 world capitals.
Also under Kelly, the NYPD has built one of the nation's most sophisticated municipal surveillance networks, which includes license plate readers, surveillance cameras and innovative investigative technologies that sift through a growing store of vast NYPD databases.
While Kelly's tenure has been transformative in many respects, it has also been marked by controversy in recent years, including the department's monitoring of Muslim communities and persistent charges of precinct-level crime data manipulation.
New York Governor Andrew Cuomo, local district attorneys and an array of civil liberties and civil rights groups all expressed support for Bratton's appointment.
"We look forward to working with the new mayor and police commissioner to ensure that fundamental changes are made to the NYPD, including a top-to-bottom culture shift that ends racial profiling and the abuse of stop-and-frisk," said Donna Lieberman, executive director of the New York Civil Liberties Union. (Reporting by Chris Francescani; Editing by Edith Honan and Jeffrey Benkoe)