Universal jurisdiction or universality principle is a principle in public international law (as opposed to private international law) whereby states claim criminal jurisdiction over persons whose alleged crimes were committed outside the boundaries of the prosecuting state, regardless of nationality, country of residence, or any other relation with the prosecuting country. The state backs its claim on the grounds that the crime committed is considered a crime against all, which any state is authorized to punish, as it is too serious to tolerate jurisdictional arbitrage.
The concept of universal jurisdiction is therefore closely linked to the idea that certain international norms are erga omnes, or owed to the entire world community, as well as the concept of jus cogens – that certain international law obligations are binding on all states and cannot be modified by treaty. 
According to critics, the principle justifies a unilateral act of wanton disregard of the sovereignty of a nation or the freedom of an individual concomitant to the pursuit of a vendetta or other ulterior motives, with the obvious assumption that the person or state thus disenfranchised is not in a position to bring retaliation to the state applying this principle.
The concept received a great deal of prominence with Belgium's 1993 "law of universal jurisdiction", which was amended in 2003 in order to reduce its scope following a case before the International Court of Justice regarding an arrest warrant issued under the law, entitled Case Concerning the Arrest Warrant of 11 April 2000 (Democratic Republic of the Congo v. Belgium). The creation of the International Criminal Court (ICC) in 2002 reduced the perceived need to create universal jurisdiction laws, although the ICC is not entitled to judge crimes committed before 2002.
According to Amnesty International, a proponent of universal jurisdiction, certain crimes pose so serious a threat to the international community as a whole, that states have a logical and moral duty to prosecute an individual responsible for it; no place should be a safe haven for those who have committed genocide, crimes against humanity, extrajudicial executions, war crimes, torture and forced disappearances.
Opponents, such as Henry Kissinger, argue that universal jurisdiction is a breach on each state's sovereignty: all states being equal in sovereignty, as affirmed by the United Nations Charter, "Widespread agreement that human rights violations and crimes against humanity must be prosecuted has hindered active consideration of the proper role of international courts. Universal jurisdiction risks creating universal tyranny — that of judges." According to Kissinger, as a practical matter, since any number of states could set up such universal jurisdiction tribunals, the process could quickly degenerate into politically-driven show trials to attempt to place a quasi-judicial stamp on a state's enemies or opponents.
The United Nations Security Council Resolution 1674, adopted by the United Nations Security Council on April 28, 2006, "Reaffirm[ed] the provisions of paragraphs 138 and 139 of the 2005 World Summit Outcome Document regarding the responsibility to protect populations from genocide, war crimes, ethnic cleansing and crimes against humanity" and commits the Security Council to action to protect civilians in armed conflict.
There is disagreement over whether universal jurisdiction is an old or new concept. Kenneth Roth, the executive director of Human Rights Watch, argues that universal jurisdiction has been around for a long time and gives examples that include American municipal legislation on aircraft hijacking dating from 1970, and that the concept of universal jurisdiction allowed Israel to try Adolf Eichmann in Jerusalem in 1961. Roth also argues that given the wide acceptance of clauses in treaties such as the Geneva Conventions of 1949 and the United Nations Convention Against Torture of 1984, which requires signatory states to pass municipal laws that are based on the concept of universal jurisdiction, it follows that such concepts are more than fifty years old. Henry Kissinger argues that it is a new one, citing the absence of the term universal jurisdiction from the sixth edition of Black's Law Dictionary, published in 1990. Furthermore,
“ The closest analogous concept listed is hostes humani generis ('enemies of the human race'). Until recently, the latter term has been applied to pirates, hijackers, and similar outlaws whose crimes were typically committed outside the territory of any state. The notion that heads of state and senior public officials should have the same standing as outlaws before the bar of justice is quite new. ”
On 14 February 2002 the International Court of Justice in the ICJ Arrest Warrant Case concluded that State officials did have immunity under international law while serving in office. The court also concluded that immunity was not granted to State officials for their own benefit, but instead to ensure the effective performance of their functions on behalf of their respective States. The court stated that when abroad, State officials enjoy full immunity from arrest in another State on criminal charges, including charges of war crimes or crimes against humanity. The ICJ did qualify its conclusions, stating that State officers "may be subject to criminal proceedings before certain international criminal courts, where they have jurisdiction. Examples include the International Criminal Tribunal for the former Yugoslavia, and the International Criminal Tribunal for Rwanda . . . , and the future International Criminal Court."
In 2003 Charles Taylor, the former president of Liberia, was served with an arrest warrant by the Special Court for Sierra Leone (SCSL) that was set up under the auspices of a treaty that binds only the United Nations and the Government of Sierra Leone. This is different from the International Criminal Tribunal for the former Yugoslavia and the International Criminal Tribunal for Rwanda (that were specifically mentioned in the ICJ Arrest Warrant Case), that were set up under the UN Security Council, acting under Chapter VII of the United Nations Charter that grant powers to the Security Council that are binding on all UN member states. In this respect the SCSL is more like the International Criminal Court that although it denies immunity to Heads of State, States that are parties to the Rome Statute would be in violation of the ICJ ruling if they handed over a visiting head of state of a non-party State to the ICC. In examining the status of the SCSL Cesare Romano and André Nollkaemper argue that:
If one considers the SCSL as an international legal person (like some treaty-based international organizations), it would arguably be bound by customary law, including international law on immunities. As to Sierra Leone, it might be argued that what Sierra Leone could not have done unilaterally, it cannot do by participating in the creation of an international court. However, there is one relevant difference between the facts of the Arrest Warrant case and the indictment of Mr. Taylor. The Security Council's support for the Court and its express call to Liberia to cooperate (even if not under Chapter VII) give indictments by the SCSL a degree of legitimacy that unilateral state action lacks.
The questions of the international legal status of the SCSL, its obligations under international law and any remaining obligations of the founding entities are complicated by the hybrid nature of the Court. The SCSL is one of a new brand of internationalized criminal bodies, composed of both international and national judges and applying international as well as national law. It shares these features with the Serious Crimes Panels in the District Court of Dili (East-Timor), the Panels in the Courts of Kosovo, and the Extraordinary Chambers in the Courts of Cambodia. Each of these courts is located between the international and national legal order and principles of international law that were developed for an interstate context may not apply automatically in regard of them.
... The retention of the immunity of former heads of states for acts committed in their official capacity has been one of the most critiqued parts of the ICJ judgment. The judgment also leaves open some room for doubt as to what exactly are acts committed in an official capacity. ... [and] the practice of States and courts in this area remains fluid and clear standards have not yet emerged, but the immunity of high States' officials is gradually being reduced.
— Cesare P.R. Romano and André Nollkaemper. The Arrest Warrant Against The Liberian President, Charles Taylor
International jurisdiction differs from "territorial jurisdiction", where justice is exercised by a state in relation to crimes committed on its territory (territorial jurisdiction). States can also exercise jurisdiction on crimes committed by their nationals abroad (extraterritorial jurisdiction), even if the act the national committed was not illegal under the law of the territory in which an act has been committed. As an example, the American PROTECT Act of 2003 asserts jurisdiction over American citizens traveling abroad.
States can also in certain circumstances exercise jurisdiction over acts committed by foreign nationals on foreign territory. This form of jurisdiction tends to be much more controversial. Bases on which a state can exercise jurisdiction in this way:
* The least controversial basis is that under which a state can exercise jurisdiction over acts that affect the fundamental interests of the state, such as spying, even if the act was committed by foreign nationals on foreign territory. The Information Technology Act 2000 of India largely supports the extraterritoriality of the said Act. The law states that a contravention of the Act that affects any computer or computer network situated in India will be punishable by India – irrespective of the culprits location and nationality.
* Also relatively non-controversial is the ability of a state to try its own nationals from crimes committed abroad. Some nations such as France as a matter of law will refuse to extradite its own citizens, but will instead try them for crimes committed abroad.
* More controversial is the exercise of jurisdiction where the victim of the crime is a national of the state exercising jurisdiction. In the past some states have claimed this jurisdiction (e.g., Mexico), while others have been strongly opposed to it (e.g., the United States, except in cases in which an American citizen is a victim). In more recent years however, a broad global consensus has emerged in permitting its use in the case of torture, "forced disappearances" or terrorist offences (due in part to it being permitted by the various United Nations conventions on terrorism); but its application in other areas is still highly controversial. For example, former dictator of Chile Augusto Pinochet was arrested in London in 1998, on Spanish judge Baltazar Garzon's demand, on charges of human rights abuses, not on the grounds of universal jurisdiction but rather on the grounds that some of the victims of the abuses committed in Chile were Spanish citizens. Spain then sought his extradition from Britain, again, not on the grounds of universal jurisdiction, but by invoking the law of the European Union regarding extradition; and he was finally released on grounds of health. Argentinian Alfredo Astiz's sentence is part of this juridical frame.
Universal jurisdiction asserted by a state must also be distinguished from the jurisdiction of an international tribunal, such as the International Criminal Court, established in 2002, the International Criminal Tribunal for Rwanda (1994) and International Criminal Tribunal for the Former Yugoslavia (1993), or the Nuremberg Trials (1945–49). In these cases criminal jurisdiction is exercised by an international organization, not by a state. The legal jurisdiction of an international tribunal is dependent on powers granted to it by the states that established it. In the case of the Nuremberg Trials, the legal basis for the tribunal was that the Allied powers were exercising German sovereign powers transferred to them by the German Instrument of Surrender.
States parties to the Statute of the International Criminal Court (light green means ratification or accession deposited but not yet in force, brown means signed but not yet ratified).
Established in The Hague in 2002, the International Criminal Court (ICC) is an international tribunal empowered with the right to prosecute state-members' citizens for genocide, crimes against humanity, and war crimes, as defined by several international agreements, most prominently the Rome Statute of the International Criminal Court signed in 1998. It provides for ICC jurisdiction over-state party or on the territory of a non-state party where that non-state party has entered into an agreement with the court providing for it to have such jurisdiction in a particular case.
However, Amnesty International argues that since the end of the Second World War more than a dozen states have conducted investigations, commenced prosecutions and completed trials based on universal jurisdiction for the crimes or arrested people with a view to extraditing the persons to a state seeking to prosecute them. These states include: Australia, Austria, Belgium, Canada, Denmark, France, Germany, Israel, Mexico, Netherlands, Senegal, Spain, Switzerland, the United Kingdom and the United States.
All states parties to the Convention against Torture and the Inter-American Convention are obliged whenever a person suspected of torture is found in their territory to submit the case to their prosecuting authorities for the purposes of prosecution, or to extradite that person. In addition, it is now widely recognized that states, even those that are not states parties to these treaties, may exercise universal jurisdiction over torture under customary international law.