Attorney General Merrick Garland announced the inquiry a day after a jury convicted former officer Derek Chauvin on murder charges in the death of George Floyd.
The guilty verdict against the former officer has added new urgency around stalled talks on legislation to ban chokeholds and end qualified immunity for police. But the path remains far from clear.
"It would have been unimaginable just even a month ago that something like that was possible," activist and civil rights lawyer Nekima Levy Armstrong says following Derek Chauvin's murder conviction.
Derek Chauvin is scheduled to be sentenced in June. Later this summer, his three fellow former officers are slated to go on trial on charges of aiding and abetting murder.
Across the country, jubilation and relief broke out at the guilty verdict for the former Minneapolis police officer. But many people see it as the start of a long fight toward justice.
George Floyd's siblings shared their relief and trauma after the guilty verdict of the ex-cop who killed their brother. "The world saw his life being extinguished and I could do nothing but watch."
"It was a murder in the full light of day, and it ripped the blinders off for the whole world to see [systemic racism]," the president said after the guilty verdict against Derek Chauvin.
A jury has found Derek Chauvin guilty on all three counts he faced over the killing of George Floyd. The outcome was far from guaranteed, as convictions of police officers are historically rare.
"George Floyd! Justice!" yelled the crowd gathered outside the Hennepin County Government Center after the jury convicted former police officer Derek Chauvin.
Chauvin, a former Minneapolis police officer, has been found guilty of unintentional second-degree murder, third-degree murder and second-degree manslaughter.
"We know that true justice is about much more than a single verdict in a single trial," the nation's first Black president and the former first lady said in a statement.
The jury has found former Minneapolis police officer Derek Chauvin guilty of the murder of George Floyd. As the country reacts, NPR revisits key moments from the last three weeks.
Republicans criticized the California Democrat's remarks urging protesters to "get more confrontational" if former Minneapolis police officer Derek Chauvin is acquitted in his trial.
The group is more racially diverse than Hennepin County, Minn., as a whole: Six are white, four are Black, and two identify as multiracial. Derek Chauvin's fate is now in their hands.
