By Julia Edwards
WASHINGTON, Sept 4 (Reuters) - The U.S. Justice Department announced on Thursday it will launch a civil investigation into the police department in Ferguson, Missouri, where unarmed black teenager Michael Brown was shot and killed by a white policeman last month.
The probe is the second federal investigation spurred by Brown's death at the hands of police officer Darren Wilson, which sparked days of sometimes violent protests in Ferguson. The Justice Department is simultaneously investigating possible criminal charges against the police officer who shot Brown.
Attorney General Eric Holder, who visited Ferguson after the shooting, said residents there "consistently expressed concerns" and "deep mistrust" of the police, prompting the federal investigation.
Holder said he has not ruled out widening the investigation into other jurisdictions in the Ferguson area, including St. Louis County. Civil rights groups have called for a broader investigation.
The probe will examine how the Ferguson police use force, conduct stops, searches and arrests, how they treat detainees, and whether they engage in discriminatory practices, said Molly Moran, assistant attorney general for the civil rights division.
Brown's family said they were encouraged by the launch of the investigation.
"We believe that transparency in law enforcement is the only way to build trust in the community, not just in the killing of Michael Brown, but for others who have suffered as well," said Benjamin Crump, a lawyer for the Brown family, in a statement.
Civil rights groups have called on the Justice Department to investigate whether Brown's shooting was motivated by racism, a problem that protesters in Ferguson say is systemic in the police department.
Wilson's defenders say the officer was acting in self defense during an altercation with Brown.
Protests in Ferguson have been muted since last week. There are still small, ongoing peaceful demonstrations calling for the local prosecutor in the case to step down.
The Justice Department's civil rights division, which is leading both investigations, has typically been more successful in bringing civil charges against entire police departments rather than criminal charges against individual officers.
While prosecutors would have to show Wilson intentionally used excessive force against Brown to bring criminal charges, a civil investigation could bring court-enforceable changes to any patterns and practices deemed a potential threat to civil rights.
Most recently, police departments in Detroit, Michigan, and Albuquerque, New Mexico, agreed to measures put in place by the civil rights division to address use of force and detention practices and unreasonable use of deadly force, respectively.
The outcome of federal intervention is hard to quantify, said former civil rights division lawyer Michael Selmi.
Selmi pointed to the Justice Department's intervention in the Los Angeles Police Department in 2001, which lasted 13 years. "Is there less police abuse in L.A.? Hopefully. Is that a result of the agreement with the Justice Department? That's really hard to know," Selmi said. (Reporting By Julia Edwards; Additional reporting by Aruna Viswanatha in Washington and Cary Gillam in Kansas City; Editing by John Whitesides and Cynthia Osterman)