US President-elect Joe Biden has nominated federal appeals court judge Merrick Garland as his attorney general.
Biden made the announcement at a news conference in his home state of Delaware on Thursday.
The new attorney general is to decide whether to start investigations into the various allegations against President Donald Trump after he leaves office.
Trump is suspected of obstructing justice in connection with the alleged Russian interference in the 2016 presidential election. He has also been accused of tax fraud.
Trump has been exempt from facing criminal charges as an incumbent president.
The new attorney general will also oversee the investigation into the tax affairs of Biden's son, Hunter.
Garland's appointment will have to be confirmed by Congress.
He was nominated as a Supreme Court justice by former President Barack Obama in 2016, but was not confirmed because the Republicans rejected the deliberations.