For the purposes
of this Convention, the term "torture" means any act by which severe
pain or suffering, whether physical or mental, is intentionally inflicted on a
person for such purposes as obtaining from him or third person information or
a confession, punishing him for an act he or a third person has committed or is
suspected of having committed, or intimidating or coercing him or a third
person, or for any reason based on discrimination of any kind when such pain
or suffering is inflicted by or at the instigation of or with the consent or
acquiescence of a public official or other person acting in an official
capacity.