The Minnesota attorney general, Keith Ellison, has announced charges against three former police officers in the death of George Floyd, and increased the charge against the officer who kneeled on the man’s neck.
“We’re confident in what we’re doing,” Ellison told a press conference on Wednesday. “But history does show that there are challenges here.”
In recent years, across the US, high-profile cases across in which African Americans were killed by police officers have rarely resulted in criminal charges or convictions.
Asking for “continued patience”, Ellison noted that the county prosecutor in the case, Mike Freeman, had previously successfully prosecuted a murder case involving a police officer.
Floyd, 46, died last week after Derek Chauvin, one of four officers involved in his arrest in Minneapolis, kneeled on his neck for nearly nine minutes. A local medical examiner ruled the death a homicide.
Chauvin was arrested and charged with third-degree murder last week. On Wednesday, Ellison increased that charge to second-degree murder.
In a statement released by civil rights attorney Benjamin Crump, the Floyd family said Ellison had informed them that “his office will continue to investigate and will upgrade the charges to first-degree murder if the evidence supports it”.
Ellison also announced charges of aiding and abetting murder against officers J Alexander Kueng, Tou Thao and Thomas Lane.
All four men were fired in the immediate aftermath of Floyd’s death, which was filmed by a witness. Kueng, Thao and Lane were not arrested and were reported to have gone to ground.
Protests against police brutality and racism touched off by Floyd’s death have spread across the US. Amid widespread confrontation with law enforcement and sporadic episodes of destruction of property, the US has experienced its worst civil unrest since the assassination of Martin Luther King Jr in 1968.
Donald Trump has expressed support for peaceful protests. But the president has also called for governors to use the national guard to “dominate” protesters and threatened to send in regular army units.
Demonstrations in support of protesters in the US have been seen in cities around the world.
On Wednesday, the Floyd family thanked supporters and said: “This is a bittersweet moment … We are deeply satisfied that Attorney General Keith Ellison took decisive action.”
Floyd was arrested after a grocery store reported that someone had used a counterfeit $20 bill.
His family said the four officers “knew they could act with impunity, given the Minneapolis police department’s widespread and prolonged pattern and practice of violating people’s constitutional rights”.
On Tuesday, Minnesota’s governor, Tim Walz, and the state department of human rights launched a civil rights investigation of the Minneapolis police.
On Wednesday, Ellison, a former member of the US House of Representatives, said: “George Floyd mattered.” But the additional charges, he said, would not on their own rectify “the hurt and loss that so many people feel”.
“Our country has underprosecuted these matters,” Ellison said, adding: “We can’t control the past. All we can do is take the case that we have in front of us right now and do our good faith best to bring justice to this situation, and we will.”
The family statement added: “This is a significant step forward on the road to justice, and we are grateful that this important action was brought before George Floyd’s body is laid to rest.”
A memorial service will be held in Minneapolis on Thursday before a funeral in Houston next week. Floyd grew up in Texas.