'Over the past decade, dozens of current and former detainees and their civilian and military attorneys have alleged in news reports and in court documents that prisoners held by the US government in Guantanamo, Iraq and Afghanistan were forcibly injected with unknown medications and pills during or immediately prior to marathon interrogation sessions in an attempt to compel them to confess to terrorist-related crimes of which they were accused.

The inspector general's investigation was unable to substantiate any of the allegations by current and former detainees that, as a matter of government policy, they were given mind-altering drugs "to facilitate interrogation."'

Read more: DoD Report Reveals Some Detainees Interrogated While Drugged, Others 'Chemically Restrained'