Central Intelligence Agency interrogators who tortured detainees during the administration of George W. Bush will not be prosecuted, President Barack Obama said on Thursday as his administration released legal memos that Mr Bush used to justify harsh techniques such as waterboarding.

In releasing the documents, which underpinned the Bush administration’s “war on terror” detention and interrogation policies, Mr Obama said CIA employees should not be punished for “relying in good faith” on legal authorisations provided by the Bush-era justice department.