In the case of Filartiga v. Pena-Irala, the 2nd Circuit Court ruled that "torture perpetrated by a person invested with official authority violates universally accepted human rights norms, regardless of the nationality of the parties. Whenever an alleged torturer is found and served with process by an alien within US territory, 28 U.S.C. § 1350 applies and provides federal jurisdiction". The opinion by Justice Kaufman stated that "Although torture was once a routine concomitant of criminal interrogations in many nations, during the modern and hopefully more enlightened era it has been universally renounced. According to one survey, torture is prohibited, expressly or implicitly, by the constitutions of over fifty-five nations, (12) including both the United States".
In a separate case, charges were brought against Rumsfeld, and others, in German courts. The plaintiffs in this case, filed in November 2006, include former prisoners of the Abu Ghraib facility in Iraq. According to a report by Time, the interrogation log of Mohammad al-Qahtani reveals that a "special interrogation plan" approved by Rumsfeld was used to produce intelligence information. Germany law provides "universal jurisdiction" – echoing Filartiga , granting the prosecution for war crimes wherever they may occur. Furthermore, the case contests, Rumsfeld's resignation alleviates claims of diplomatic immunity.
Through the efforts of Senator John McCain, Congress passed the Detainee Treatment Act, (DTA) which excludes the use of inhumane treatment against those in US custody. However, the Graham-Levin amendment was seen to diminish the DTA, as the latter permits coerced testimonial. The legal definition of torture, however, remains contentious and beyond the scope granted here.
The Military Commissions Act, a response to Hamdan v. Rumsfeld, blocks the prosecution of those accused of abuses. In addition, the US has reversed its signing of the Rome Statute, which refuses US participation in the International Criminal Court. In a Texas case (Medellin v. Texas), the US has urged for the reversal of that courts ruling ensuring compliance with decisions emanating from the International Court of Justice at The Hague. The government's position argues that the previous rulings undermine presidential authority to interpret treaty obligations. Citing Youngstown Sheet and Tube v. Sawyer, the government argued that presidential powers were at their pinnacle during times of war recognized by Congress. Solicitor General Paul Clement stated that "the Optional Protocol and the UN Charter are most sensibly read to entrust the President with the responsibility of deciding how to respond to an ICJ decision." The defense countered, also from Youngstown, that presidential powers "are limited to executing, not creating law", arguing plenary executive privilege.
Links to the Rome Statute et al are in the sidebar.
Quotes from General Clement are taken from SCOTUSblogs reporting.