This UN Declaration, adopted on December 9, 1975, explicitly prohibited the use of torture by states, under any circumstances.
In Article 1, the Declaration defined torture:
For the purpose of this Declaration, torture means any act by which severe pain or suffering, whether physical or mental, is intentionally inflicted by or at the instigation of a public official on a person for such purposes as obtaining from him or a third person information or confession, punishing him for an act he has committed or is suspected of having committed, or intimidating him or other persons. It does not include pain or suffering arising only from, inherent in or incidental to, lawful sanctions to the extent consistent with the Standard Minimum Rules for the Treatment of Prisoners
Article 3 made it clear that there are no circumstances legitimating torture:
No State may permit or tolerate torture or other cruel, inhuman or degrading treatment or punishment. Exceptional circumstances such as a state of war or a threat of war, internal political instability or any other public emergency may not be invoked as a justification of torture or other cruel, inhuman or degrading treatment or punishment.