Article 3 of the UDHR states: “Everyone has the right to life, liberty and security of person.” Article 5 adds: “No one shall be subjected to torture or to cruel, inhuman or degrading treatment or punishment.” These are among the most widely accepted of all rights. Three topics show how they work in practice: genocide, torture and the death penalty.

Genocide

The word genocide was coined in 1944 by Raphael Lemkin, a Polish Jewish lawyer, from the Greek genos (people or kind) and the Latin -cide (killing). He was trying to name a crime that existing law did not cover: the attempt to destroy a whole group. After the Holocaust, Lemkin campaigned tirelessly, and on 9 December 1948, the day before the UDHR, the UN adopted the Genocide Convention.

The Convention defines genocide as certain acts committed with intent to destroy, in whole or in part, a national, ethnic, racial or religious group. These acts include killing members of the group, causing them serious harm, imposing conditions meant to destroy the group, preventing births and forcibly transferring children. The key element is intent to destroy the group as such, which makes genocide hard to prove. States that join must prevent and punish it. In 1998 the international tribunal for Rwanda issued the first conviction for genocide by an international court.

Torture

The ban on torture is one of the few rights treated as absolute. The Convention against Torture (1984) says that no exceptional circumstances whatsoever, including war or public emergency, can justify torture. States must also not send a person to another country where they would face a real risk of torture, a rule called non-refoulement.

Some have challenged the absolute ban with the “ticking bomb” scenario: if a captured terrorist knows where a bomb will explode in a city, should officials torture him to save many lives? Defenders of an exception argue that preventing mass death outweighs harm to one guilty person. Defenders of the absolute ban reply that real cases are never so certain, that torture often produces false information, that permitted torture spreads into routine use and corrupts the institutions that practice it, and that some acts are wrong whatever their results.

The death penalty

The death penalty is a genuine area of disagreement in international law and among thoughtful people. The ICCPR protects the right to life but allows countries that have not abolished capital punishment to use it only for the most serious crimes, after a fair trial. A Second Optional Protocol (1989) commits states that join it to abolition. More than two-thirds of the world's countries have abolished it in law or in practice, while several large countries retain it.

Arguments for, as supporters make them: justice requires that punishment fit the crime, and some crimes are so grave that only death is proportionate. The philosopher Immanuel Kant held this retributive view. Supporters also argue that it may deter some killers, permanently protects society, and honors the victims and their families.

Arguments against: courts make mistakes, and an execution cannot be undone; people sentenced to death have later been shown to be innocent. Critics also point to evidence that the penalty falls unequally on the poor and on minorities, that studies have not clearly shown it deters better than long imprisonment, and that a state should not deliberately kill a captive person. The Italian thinker Cesare Beccaria, in On Crimes and Punishments (1764), made one of the first influential arguments for abolition. Supporters reply that careful procedures, repeated appeals and modern evidence such as DNA testing can greatly reduce the risk of error, and that some crimes deserve the penalty however rarely it is used.

Notice that both sides appeal to values found in the human rights tradition: justice for victims and the dignity of every person, including the guilty.

Worked example: testing the ticking bomb

The ticking bomb scenario is a thought experiment, so it is worth testing its assumptions one by one against how real situations tend to unfold.

• Officials know there is a bomb. In real cases, intelligence is usually partial and uncertain.
• They have the right person. Real detainees are sometimes innocent or only loosely connected.
• The person knows the location. He may not, or may know only part of it.
• Torture will produce true information in time. A person in agony may say anything to make it stop, sending officials in the wrong direction.
• It will happen only once. Once torture is permitted in extreme cases, interrogators must be trained, methods developed and legal cover provided. Experience suggests the practice then spreads to less extreme cases.

Supporters of an exception can reply that even if real cases are rare, the principle matters: if all five conditions were met, refusing to act would let many innocent people die. Some have proposed that any torturer should face trial and plead necessity, so that the ban stays in the law while extreme cases are judged afterward.

Defenders of the absolute ban answer that the law should be written for the world as it is, not for idealized hypotheticals, and that a rule with no exceptions is easier to keep than one with a door left open. This is why international law, after long experience, chose an absolute rule.