Or more specifically, what is a reasonable ground to believe that an act of torture has been committed. But that isn't an argument that anyone is seriously making any more. Waterboarding is Torture, according to the incoming AG and everyone else in the incoming administration. See what at difference that makes? Waterboarding has been done and been admitted to, and it's torture.
Is anyone arguing that we don't have reasonable grounds to believe that waterboarding occurred, or that it isn't torture? If it's reasonable to believe this stuff is true, then there is no wiggle-room under the law. It shall be investigated. Period.
The
"investigation" is mandatory in accordance with Article 12 but that particular article is silent on prosecution, IMHO. You would have to look at Articles 6 and 7 for detention and prosecution:
Article 6
1. Upon being satisfied, after an examination of information available to it, that the circumstances so warrant, any State Party in whose territory a person alleged to have committed any offence referred to in article 4 is present, shall take him into custody or take other legal measures to ensure his presence. The custody and other legal measures shall be as provided in the law of that State but may be continued only for such time as is necessary to enable any criminal or extradition proceedings to be instituted.
2. Such State shall immediately make a preliminary inquiry into the facts.
3. Any person in custody pursuant to paragraph 1 of this article shall be assisted in communicating immediately with the nearest appropriate representative of the State of which he is a national, or, if he is a stateless person, to the representative of the State where he usually resides.
4. When a State, pursuant to this article, has taken a person into custody, it shall immediately notify the States referred to in article 5, paragraph 1, of the fact that such person is in custody and of the circumstances which warrant his detention. The State which makes the preliminary inquiry contemplated in paragraph 2 of this article shall promptly report its findings to the said State and shall indicate whether it intends to exercise jurisdiction.
Article 7
1. The State Party in territory under whose jurisdiction a person alleged to have committed any offence referred to in article 4 is found, shall in the cases contemplated in article 5, if it does not extradite him, submit the case to its competent authorities for the purpose of prosecution.
2. These authorities shall take their decision in the same manner as in the case of any ordinary offence of a serious nature under the law of that State. In the cases referred to in article 5, paragraph 2, the standards of evidence required for prosecution and conviction shall in no way be less stringent than those which apply in the cases referred to in article 5, paragraph 1.
3. Any person regarding whom proceedings are brought in connection with any of the offences referred to in article 4 shall be guaranteed fair treatment at all stages of the proceedings. As far as any interpretation of the phrase
"any Thing in the Constitution or Laws of any State to the Contrary notwithstanding" goes, the treaty becomes the law of the land, that is why the Senate must ratify all treaties by a super majority. It binds every judge in every state. A treaty may not do or exceed what the Congress is charged to do or what it is forbidden to do. A treaty remains subordinate, and Constitutional authority supersedes, overrules, and precludes any contrary treaty authority.
There is no contrary authority in the Constitution (especially in this article), or any existing law which I am aware of, that would preclude any torture investigation, or one that carves out an exception for the president to authorize torture in violation of the law. If there is, you will have to explain it to me.