US president Barack Obama plans to name James Comey, a former senior official in the administration of George W Bush, as his nominee to replace Robert Mueller as FBI director.
Mr Comey (52), a former senior official at the justice department, is best known for his dramatic opposition to attempts by the Bush administration to renew the eavesdropping on electronic communications of US citizens without first obtaining warrants.
In 2004, when White House counsel Alberto Gonzales and chief of staff Andrew Card attempted to persuade attorney general John Ashcroft, who was in a Washington hospital, to reauthorise the eavesdropping programme, Mr Comey famously rushed to Mr Ashcroft’s bed to object.
Mr Comey, along with Mr Mueller, threatened to resign if the White House continued the programme and the administration backed down. He also opposed the Bush administration’s use of interrogation techniques and torture under the CIA, including the simulated drowning of detainees known as waterboarding.
Mr Mueller, the longest-serving FBI director since J Edgar Hoover, the bureau's legendary founder, took up the role shortly before the September 2001 attacks. He had extended his normal 10-year tenure by two years in 2011 at Mr Mr Obama's request.
The appointment of Mr Comey is seen as a bipartisan move to install a candidate that might be better favoured by the president’s opponents on a gridlocked Capitol Hill.
Mr Comey's name emerged as US attorney general Eric Holder came under increased pressure over the justice department's attempts to find the source of leaks to the Associated Press and a reporter from Fox News.
Republicans have accused Mr Holder of misleading Congress when he testified on whether the justice department had ever considered prosecuting journalists under the Espionage Act for publishing official secrets.
Mr Holder told a congressional committee on May 15th that he would never personally have been involved in a possible prosecution of a journalist over the disclosure of sensitive material.
It later emerged that Mr Holder had signed off on a warrant to obtain phone and email records of James Rosen, the chief Washington correspondent of Fox News, as part of an investigation into possible leaks of classified information about North Korea in 2009.