US Attorney General Merrick Garland has appointed two special counsels for major investigations the Justice Department is conducting into President Joe Biden and former president Donald Trump.
He tapped Richard Hur to look into Mr Biden's handling of classified documents from his time as vice president in January, after assigning Jack Smith to oversee the department's investigations into Mr Trump in November last year.
An attorney general has the power to assign a special counsel, who acts as a semi-independent investigator on politically sensitive probes, to avoid the appearance of a conflict of interest.
Under US law, a special counsel can be appointed under “extraordinary circumstances”. Historically they have been appointed sparingly, but their employment has become a more consistent tactic in recent years.
During the Trump administration, former FBI director Robert Mueller investigated whether any Americans were involved with Russian interference in the 2016 presidential election.
The operation resulted in more than 30 indictments and several guilty pleas.
A redacted FBI photograph of classified documents recovered from a container in former president Donald Trump's estate at Mar-a-Lago in Palm Beach, Florida. Reuters
The FBI searched Mr Trump's home over what it said were 'likely' efforts to conceal classified files. AFP
The Mar-a-Lago property was raided by agents on August 8. Reuters
Pages from a Department of Justice court filing in response to a request from Mr Trump's legal team for a 'special master' to review the documents seized. AP
Journalists read a heavily redacted court document relating to the FBI search. AP
The former president condemned the raid as 'the weaponisation of the justice system'. AP
Pages from a Department of Justice court filing, in response to a request from Mr Trump's legal team. AP
Mr Trump had faced accusations of deleting private communications during investigations into his alleged role in the storming of the Capitol building on January 6 by his supporters. Reuters
Mr Trump departs Trump Tower for a deposition two days after the FBI agents raided his Mar-a-Lago home. Reuters
Pages of entirely redacted information in the released version of an affidavit from the US Justice Department that was submitted to a judge to support the execution of the FBI search warrant. Reuters
Mr Trump was also accused of taking a trove of classified documents from the White House, leading to speculation that those missing documents could have been the focus of the raid. Reuters
Mr Trump set up his Save America political action committee days after losing the 2020 election to Joe Biden. EPA
A Trump supporter outside the Paul S Rogers Federal Building and US Courthouse in West Palm Beach, Florida. AP
Mr Trump reportedly had more than 300 classified documents at Mar-a-Lago. AP
US Attorney General Merrick Garland speaks about the FBI's search warrant. Reuters
Other uses of the special counsel include former president Richard Nixon's Watergate scandal in the 1970s, which eventually led to his resignation from office.
A special counsel was also used during the Iran-Contra affair, which occurred under former president Ronald Reagan, as well as during investigations into Bill Clinton's personal involvement in state-level real estate investments.
Per Justice Department rules, a special counsel must come from outside the government to maintain as much impartiality as possible.
Watergate scandal turns 50 — in pictures Former US president Richard Nixon points to transcripts of tapes after he announced during a televised speech that he would turn them over to House of Representatives impeachment investigators during the Watergate scandal. AP
John Ehrlichman, a key figure in the Watergate scandal, was convicted of conspiracy and perjury and served 18 months in prison. AP
FBI official Mark Felt was the 'Washington Post' informant that helped them break the Watergate story. AP
Nixon tells a group of Republican campaign contributors that he will get to the bottom of the Watergate scandal during a speech on May 9, 1973, in Washington. AP
The Senate Watergate Committee hearings on Capitol Hill in Washington took place in 1973. AP
HR Haldeman, former top Nixon aide, speaks before the Senate Watergate Committee in Washington on July 31, 1973. AP
Named in the Watergate scandal, from left to right, are G Gordon Liddy, White House counsel John W Dean III, former attorney general John Mitchell, and former Nixon deputy campaign manager Jeb Stuart Magruder. AP
Howard Baker, vice chairman of the Senate Watergate Investigating Committee, questions James McCord during a hearing in Washington, on May 18, 1973. AP
Nixon says goodbye with a victorious salute to his staff members outside the White House as he boards a helicopter after resigning the presidency on August 9, 1974. AP
The traumas of Watergate and January 6 are a half century apart, in vastly different eras, and they were about different things. AP
Nixon gives a speech at the White House following his resignation from the presidency after the Watergate scandal. Consolidated News Pictures / AFP
Parking space D32 in the garage underneath the Oakhill Office Building, where 'Washington Post' reporter Bob Woodward would meet his source known as 'Deep Throat' to exchange notes about the Watergate scandal, in Rosslyn, Virginia. Getty Images / AFP
Evidence from the Watergate break-in at the Democratic National Committee headquarters in Washington. AFP
The Watergate buildings feature office suites, a hotel and single-family residences. Getty Images / AFP
Woodward was a cub reporter when he and veteran 'Washington Post' reporter Carl Bernstein broke the Watergate story. AFP
A break-in by five men looking to install microphones at the Watergate and take pictures of documents to find compromising information on Nixon's opponents led to the president's downfall. AFP
Former 'Washington Post’s' executive editor Ben Bradlee and publisher Katharine Graham seen leaving the US district court in Washington. AP
Nixon met football star Pele in 1973 as rumblings of the Watergate scandal were beginning to surface. Photo: US National Archives
A wanted poster features key people involved in the Watergate scandal at the National Portrait Gallery in Washington. EPA
The exhibition presents illustrations from the 50th anniversary of the Watergate scandal. EPA
A photograph of Mark Felt and 'Time' magazine cover artwork called 'Nixon's Palace Guard' are part of the display. EPA
Pulitzer Prize-winning journalist Carl Bernstein eulogises his former boss and 'Washington Post' executive editor Ben Bradlee at the National Cathedral in Washington. Getty Images / AFP
A caricature which appeared on the cover of 'Time' magazine in April 1973. EPA
The luxurious Watergate complex in Washington where the Democratic National Committee had its offices in 1973. AP
The exterior of the modern Watergate Hotel in Washington. Photo: Ron Blunt
The location of the clandestine meetings between Woodward and Mark Felt in 1972 and 1973 were kept secret until Felt came forward and revealed himself to be Deep Throat in 2005. Getty Images / AFP
A historical marker stands outside the parking garage underneath the Oakhill Office Building in Rosslyn, Virginia. Getty Images / AFP
Ben Bradlee, actor Dustin Hoffman and Harry Rosenfeld talk at the premiere of 'All the President's Men' at the Kennedy Centre in Washington. The Washington Post / AP
Updated: January 12, 2023, 11:16 PM