Torture—the infliction of severe physical or mental suffering—is frequently a component of systematic policies and attacks against individuals or groups, in peacetime or in time of war. Torture is used variously as a weapon of war, as a means of soliciting information or confession, as a technique to humiliate or punish, as a tool of repression or intimidation, and as a form of sexual violence. Its typical victims include political opponents; particular national, racial, ethnic, religious or other groups; women; prisoners of war; detainees; and ordinary criminal suspects.

In response, international law has prohibited torture and other cruel, inhuman or degrading treatment in absolute terms. The prohibition of torture and other forms of ill treatment ranks among the most firmly entrenched principles of international law regarding human rights and of international humanitarian law. The right not to be tortured is based on the...