WASHINGTON: The US Justice Department announced Wednesday an investigation into the police department of Minneapolis, Minnesota, signalling the Biden administration's intention to use federal powers to clean up systemic police abuse.

One day after former Minneapolis officer Derek Chauvin was convicted of murdering African-American George Floyd, US Attorney General Merrick Garland said the department aimed to "determine whether the Minneapolis Police Department engages in a pattern or practice of unconstitutional or unlawful policing."

He said the probe will examine whether the police systematically engaged in the use of excessive force, including during legal protests.

It will also examine whether the city force showed a pattern of discrimination and unlawful treatment of people with behavioral health disabilities.

The announcement signalled an about-face by President Joe Biden from the previous administration of Donald Trump, which refused to pressure police departments despite mounting evidence of racist and abusive practices in a number of cities.

Garland said the return to such investigations, which aim at forcing police departments to accept reforms under legally binding agreements, was important to restore confidence in police.

"Building trust between community and law enforcement will take time and effort by all of us. But we undertake this task with determination and urgency, knowing that change cannot wait," he said.