CIA officials will not be prosecuted for having used waterboarding and other harsh interrogation methods on terrorism suspects under the Bush administration.
In giving the assurance, US President Barack Obama made clear that his decision did not take away from his own disapproval of the interrogation methods that had been employed in the name of the "war on terrorism."
"The men and women of our intelligence community serve courageously on the front lines of a dangerous world," he said.
"We must protect their identities as vigilantly as they protect our security, and we must provide them with the confidence that they can do their jobs".
Mr Obama ordered a halt to such internationally condemned interrogation techniques after he took office.
The president has approved the release of government memos issued during President George W Bush's administration that authorised tough interrogation of terrorism detainees held at the Guantanamo military prison in Cuba and in secret CIA jails overseas.
The memos advised that interrogators could apply a degree of physical pain but not severe pain.
International human rights groups had denounced waterboarding, or simulated drowning, and other harsh methods as amounting to torture.
Human rights groups disappointed
On Friday human rights campaigners in the US criticised Mr Obama's statement that CIA agents will not be prosecuted for interrogation techniques used during the Bush era.
What upsets the human rights campaigners is the policy outlined by Mr Obama in a statement released at the same time as the memos.
In releasing the memos, Mr Obama said: "It is our intention to assure those who carried out their duties relying in good faith upon legal advice from the Department of Justice that they will not be subject to prosecution."
Amnesty International said a "get out of jail free card" was being offered to individuals who the Obama administration believed were involved in acts of torture.
The Centre for Constitutional Rights said the immunity now granted to CIA operatives was "deeply disappointing".