This post was updated at 5:30 p.m. ET
Attorney General Eric Holder says "far more must be done to create enduring trust" between police and communities they serve, even as his Justice Department continues to investigate possible discriminatory police actions in Ferguson, Mo.
Civil rights lawyers at Justice working alongside FBI agents have also been examining whether white officer Darren Wilson intentionally violated the civil rights of 18-year-old Michael Brown, the unarmed black man he shot dead Aug. 9.
On Tuesday, Holder spoke about the DOJ's ongoing efforts emphasizing that both federal investigations will "continue to be thorough, continue to be independent and they remain ongoing."
He did not provide a timeline for the investigations, but said they "will be conducted rigorously and in a timely manner so that we can move forward as expeditiously as we can to restore trust, to rebuild understanding, and to foster cooperation between law enforcement and community members."
Proving that Wilson, who was cleared Monday by a St. Louis County grand jury, violated federal criminal law will be difficult, DOJ veterans say.
But in the aftermath of the local grand jury announcement, Holder has insisted the federal probe of the policeman is ongoing and independent of St. Louis prosecutors.
"And although federal civil rights law imposes a high legal bar in these types of cases, we have resisted forming premature conclusions," Holder said in a statement Monday.
Mediators from the Justice Department Community Relations Service have been on the ground in Ferguson trying to ease tensions since August. And the DOJ community-oriented policing unit has been trying to train local law enforcement to respect protesters and de-escalate tensions. Scattered violence and scenes of burning businesses in the area overnight Monday mean that work is far from complete.
Justice Department lawyers are making slow but steady progress on another facet of their task in Ferguson: investigating allegations of unconstitutional policing by law enforcement there.
Holder tipped his hand last month, publicly calling for "wholesale changes" in the Ferguson force. His DOJ investigators have opened more than two-dozen investigations into biased policing tactics and patterns of excessive force in places from Albuquerque to New Orleans to Newark.
Such cases often end in lawsuits or court-enforceable agreements to change hiring, training and traffic stop actions.
Vanita Gupta, the acting leader of the civil rights division at Justice, said at a news conference last month that the goal of such cases is to "ensure that the city has an effective, accountable police department that controls crime, ensures respect for the Constitution, and earns the respect of the public it is charged with protecting."
Holder also said Tuesday he was disappointed that some reacted with violence rather than heeding the call for non-violence issued by Brown's parents.
The attorney general says his top aides will work with local police in Missouri "so that we can develop strategies for identifying and isolating the criminal elements from peaceful protesters." Holder says people in Ferguson who tried to stop looters and arsonists are "heroes, in my mind."
The issue is personal for Holder, the country's first black attorney general. He told NPR earlier this year he wanted to keep working to forge connections between police and minority communities even after he retires from public service next year.
DAVID GREENE, HOST:
Darren Wilson has now broken his silence. He's the police officer who shot and killed 18-year-old Michael Brown in Ferguson, Missouri. That killing set off a wave of protests in the community near St. Louis, and then more protests came this week after a grand jury decided not to indict Officer Wilson. Not just in Ferguson, there were protests in more than 150 U.S. cities. Last night Darren Wilson gave his first interview. He spoke with ABC's George Stephanopoulos about the shooting and about what he told a colleague shortly afterwards.
(SOUNDBITE OF ARCHIVED RECORDING)
DARREN WILSON: After the supervisor got there, I gave him the brief rundown of what had happened.
GEROGE STEPHANOPOULOS: What did you tell him?
WILSON: I told him that I had to shoot somebody. He asked me why. I said, well, he had grabbed my gun, and he had charged me. And he was going to kill me.
STEPHANOPOULOS: So you killed him first?
GREENE: This week's decision by a St. Louis County grand jury does not end the legal scrutiny of the Ferguson Police Department. Justice Department investigators are still looking at whether they can bring charges against Officer Darren Wilson. NPR's Carrie Johnson reports they are also in search of wider patterns of discrimination within the police force in Ferguson.
CARRIE JOHNSON, BYLINE: The Justice Department investigations are proceeding along two tracks. First there's the federal criminal probe of Officer Darren Wilson. To bring a case, the FBI needs to prove the white policeman intended to deprive Michael Brown, the black 18-year-old, of his civil rights. But law enforcement officers like Wilson can rely on a powerful defense, arguing they acted to protect themselves and bystanders. That's why legal experts say federal criminal charges against Wilson are unlikely. But the Justice Department has another path in Ferguson, one that could lead to lasting changes there. Sam Bagenstos teaches law at the University of Michigan.
SAM BAGENSTOS: You know, an individual criminal prosecution - it's a high bar, and even if you get a conviction that's one person who's going to prison. But a pattern or practice case can actually change a police department and make it adhere to constitutional standards.
JOHNSON: Pattern or practice, that's a kind of civil rights investigation that looks for unconstitutional policing strategies. The Justice Department's been sifting through data about the race of people Ferguson police stopped for traffic violations and how many minorities get tickets for other smalltime offenses. Bagenstos says the Justice Department's reached agreements with other cities to change hiring practices impose more training, and overhaul how and when police use weapons. The Obama Justice Department has opened more than 20 such cases all over the country, a deliberate choice Bagenstos says.
BAGENSTOS: The pattern or practice cases have been a big strategy because they can make bigger change.
JOHNSON: Attorney General Eric Holder told reporters he's pressing to finish both investigations within weeks.
(SOUNDBITE OF SPEECH)
U.S. ATTORNEY GENERAL ERIC HOLDER: They will be conducted rigorously and in a timely manner so that we can move forward as expeditiously as we can to restore trust, to rebuild understanding and to foster cooperation between law enforcement and community members.
JOHNSON: Holder says other communities around the country have issues just like Ferguson's. He says he's determined to do all he can to ease those tensions, starting with visits to several major cities to talk about best practices for police. Carrie Johnson, NPR News, Washington. Transcript provided by NPR, Copyright NPR.