Over the past several decades, multiple international agreements and declarations have condemned and/or sought to prohibit the practice of torture by public officials, leading many to conclude that torture is now prohibited under customary international law. Perhaps the most notable international agreement prohibiting torture is the United Nations Convention against Torture and Other Cruel, Inhuman, or Degrading Treatment or Punishment (Convention or CAT), signed by the United States and more than 140 other countries. Whereas a number of prior international agreements and declarations condemned and/or prohibited torture, CAT appears to be the first international agreement to actually attempt to define the term. CAT Article 1 specifies that, for purposes of the Convention, "torture" is understood to mean 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 a 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. It does not include pain or suffering arising only from, inherent in or incidental to lawful sanctions. Importantly, this definition specifies that both physical and mental suffering can constitute torture, and that for such suffering to constitute torture, it must be purposefully inflicted. Further, acts of torture covered under the Convention must be committed by someone acting under the color of law. Thus, for example, if a private individual causes intense suffering to another, absent the instigation, consent, or acquiescence of a public official, such action does not constitute "torture" for purposes of CAT. The Convention's definition of "torture" does not include all acts of mistreatment causing mental or physical suffering, but only those of a severe nature. According to the State Department's section-by-section analysis of CAT included in President Reagan's transmittal of the Convention to the Senate for its advice and consent, the Convention's definition of torture was intended to be interpreted in a "relatively limited fashion, corresponding to the common understanding of torture as an extreme practice which is universally condemned." For example, the State Department suggested that rough treatment falling into the category of police brutality, "while deplorable, does not amount to 'torture'" for purposes of the Convention, which is "usually reserved for extreme, deliberate, and unusually cruel practices ... [such as] sustained systematic beating, application of electric currents to sensitive parts of the body, and tying up or hanging in positions that cause extreme pain." This understanding of torture as a severe form of mistreatment is further made clear by CAT Article 16, which obligates Convention parties to "prevent in any territory under [their] jurisdiction other acts of cruel, inhuman, or degrading treatment or punishment which do not amount to acts of torture," thereby indicating that not all forms of inhumane treatment constitute torture. In general, Convention parties are obligated to take "effective legislative, administrative, judicial or other measures to prevent acts of torture in any territory under [their] jurisdiction." They are also forbidden from expelling, returning, or extraditing a person to another State where there are "substantial grounds" for believing that he would be in danger of being subjected to torture. A central objective of CAT is to criminalize all instances of torture. CAT Article 4 requires States to ensure that all acts of torture are criminal offenses, subject to appropriate penalties given their "grave nature." State parties are also required to apply similar criminal penalties to attempts to commit and complicity or participation in torture. Accordingly, it appears that even though CAT requires States to take "effective measures" to prevent torture only within their territorial jurisdiction, this does not mean that States are therefore permitted to engage in torture in territories not under their jurisdiction. Although a State might not be required to take proactive measures to prevent acts of torture beyond its territorial jurisdiction, it nevertheless has an obligation to criminalize such extraterritorial acts and impose appropriate penalties. CAT Article 5 establishes minimum jurisdictional measures that each State party must take with respect to offenses described in CAT Article 4. Pursuant to CAT Article 5, a State party must establish jurisdiction over CAT Article 4 offenses when The offenses are committed in any territory under its jurisdiction or on board a ship or aircraft registered in that State; The alleged offender is a national of that State; The victim was a national of that State if that State considers it appropriate; or The alleged offender is present in any territory under its jurisdiction and the State does not extradite him in accordance with CAT Article 8, which makes torture an extraditable offense. CAT's prohibition of torture is absolute: "No exceptional circumstances whatsoever, whether a state of war or a threat or war, internal political instability or any other public emergency, may be invoked as a justification of torture." According to the State Department, this blanket prohibition was viewed by the drafters of CAT as "necessary if the Convention is to have significant effect, as public emergencies are commonly invoked as a source of extraordinary powers or as a justification for limiting fundamental rights and freedoms." CAT Article 14 provides that signatory States must ensure that their legal systems provide victims of torture (or their dependents, in cases where the victim has died as a result of torture) with the ability to obtain civil redress in the form of "fair and adequate compensation including the means for as full rehabilitation as possible." According to the State Department, Article 14 was adopted with an express reference to this treaty obligation extending only to "the victim of an act of torture committed in any territory under [a signatory State's] jurisdiction ," but this limiting clause was "deleted by mistake." CAT Article 16 requires signatory States to take preventative measures to prevent "cruel, inhuman, or degrading treatment or punishment" within any territory under their jurisdiction when such acts are committed under the color of law. CAT does not define these terms, and the State Department suggested that the requirements of Article 16 concerning "degrading" treatment or punishment potentially include treatment "that would probably not be prohibited by the U.S. Constitution." Unlike in the case of torture, however, CAT does not expressly require States to criminalize acts of cruel, inhuman, or degrading treatment or punishment that occur within or outside their territorial jurisdiction. CAT also established a Committee Against Torture (CAT Committee), composed of ten experts of recognized competence in the field of human rights who are elected to biannual terms by State parties. Each party is required to submit, within a year of the Convention entering into force for it, a report to the committee detailing the measures it has taken to give effect to the provisions of CAT, as well as supplementary reports every four years on any new measures taken, in addition to any other reports the committee may request. The committee monitors State compliance with Convention obligations, investigates allegations of systematic CAT violations by State parties and makes recommendations for improving compliance, and submits annual reports to CAT parties and the U.N. General Assembly. CAT Article 30 provides that disputes between two or more signatory parties concerning the interpretation and application of the Convention can be submitted to arbitration upon request. If, within six months of the date of request for arbitration, the parties are unable to agree upon the organization of the arbitration, any of the parties may refer the dispute to the International Court of Justice. Article 30 contains an "opt-out" provision, however, that enables States (including the United States) to make a reservation at the time of CAT ratification declaring that they do not consider themselves to be bound by Article 30. The United States signed CAT on April 18, 1988, and ratified the Convention on October 21, 1994, subject to certain declarations, reservations, and understandings. Perhaps most significantly, the United States included a declaration in its instruments of ratification that CAT Articles 1 through 16 were not self-executing. The following sections discuss relevant declarations, reservations, and understandings made by the United States to CAT, and U.S. laws implementing CAT Article 4 requirements to criminalize torture. As previously mentioned, the Senate's advice and consent to CAT ratification was subject to the declaration that the Convention was not self-executing, meaning that implementing legislation was required to fulfill U.S. international obligations under CAT, and such implementing legislation was necessary for CAT to be given effect domestically. In providing its advice and consent to CAT, the Senate also provided a detailed list of understandings concerning the scope of the Convention's definition of torture. With respect to mental torture, a practice not specifically defined by CAT, the United States understands such actions to refer to prolonged mental harm caused or resulting from (1) the intentional infliction or threatened infliction of severe physical pain and suffering; (2) the administration of mind-altering substances or procedures to disrupt the victim's senses; (3) the threat of imminent death; or (4) the threat that another person will imminently be subjected to death, severe physical pain or suffering, or the administration or application of mind altering substances or other procedures calculated to disrupt profoundly the senses or personality. The Convention's definition of torture includes not only acts committed by public officials, but also those acts to which they acquiesced. As expressed in a U.S. understanding on this point, for a public official to acquiesce to an act of torture, that official must, "prior to the activity constituting torture, have awareness of such activity and thereafter breach his or her legal responsibility to intervene to prevent such activity." U.S. implementing regulations barring the removal of aliens to countries where they would more likely than not face torture reflect this understanding.