In nominating Jim Comey to be the next FBI director on Friday, President Barack Obama said the former Justice Department official will help strike a balance between the need for information on terrorist plots and respecting Americans' privacy.
The need for such balance has been brought to the fore recently with the disclosure that the U.S. government has conducted vast surveillance of Americans' phone and internet data in its search for foreign terrorism plots.
Obama used the example of a tumultuous episode from Comey's past to promote the Republican. Comey had famously refused to certify the legal aspects of National Security Agency domestic surveillance during a 2004 stint as acting attorney general while then-Attorney General John Ashcroft was hospitalized with pancreatitis.
The refusal prompted two senior White House officials - counsel Alberto Gonzales and chief of staff Andrew Card - to try to persuade Ashcroft to sign the certification. Comey, who was in the room, said Ashcroft refused.
"He was prepared to give up a job he loved rather than be part of something he felt was fundamentally wrong," Obama said in a Rose Garden ceremony to announce Comey's nomination to replace FBI Director Robert Mueller.
"Jim understands that in time of crisis, we aren't judged solely by how many plots we disrupt or how many criminals we bring to justice - we're also judged by our commitment to the Constitution that we've sworn to defend," he said.
The surveillance program resurfaced as a major bone of contention this month after disclosures about it by former government contractor Edward Snowden.
Obama said he was confident that Comey "will be a leader who understands how to keep America safe and stay true to our founding ideals, no matter what the future may bring."
Comey, 52, served as deputy U.S. attorney general for President George W. Bush. He had previously been the U.S. attorney for the Southern District of New York.
If confirmed by the Senate, he would replace FBI Director Robert Mueller, who has held the position for 12 years.
The Washington, D.C.-based Federal Bureau of Investigation serves as both a federal criminal investigative agency and a domestic intelligence body.