What Is Extradition? How One Country Hands a Suspect to Another

There is no general duty in international law to surrender a fugitive, so the whole system rests on agreements: bilateral treaties between two countries, multilateral conventions, and in Europe a framework that replaced treaty-based extradition between member states with a system of mutual recognition. Absent an agreement, a state may still surrender someone as a matter of discretion or reciprocity, and may equally refuse without explanation, which is why a person in a country with no relevant treaty is often effectively out of reach. The requesting state sends a formal request through diplomatic channels with the charge, the evidence required by the treaty and an assurance about how the person will be treated; the requested state arrests them, runs a judicial hearing on whether the legal conditions are met, and then, if they are, leaves a final decision to a government minister.

Almost every treaty carries the same set of tests, developed over two centuries and designed to stop the process being used as a weapon:

• •Dual criminality: the conduct must be a crime in both countries, and usually one carrying a minimum sentence, typically a year, so that minor matters are excluded
• •Speciality: the person may be tried only for the offence they were surrendered for, and not for something else the requesting state had in mind
• •The political offence exception: no surrender for offences of a political character, a rule with an obvious purpose and a difficult boundary, since terrorism is usually excluded from the exception by treaty
• •No surrender where the real purpose is to punish someone for their race, religion, nationality or political opinion
• •Human rights bars: no surrender to torture, to an unfair trial, or in many countries to a death sentence unless an assurance is given that it will not be sought or carried out
• •Bars for lapse of time, for double jeopardy where the person has already been tried, and often for trials held in absence unless a retrial is guaranteed
• •Nationality: many civil law states, including France, Germany and Brazil, refuse outright to surrender their own citizens, and prosecute them at home instead

The process is judicial, and it is appealable at almost every stage. A contested case runs through an initial hearing, a decision by a minister, and then appeals through the domestic courts, potentially to the highest one, and in Europe to the European Court of Human Rights, with fresh arguments available about health, changed conditions in the requesting state or delay itself. Cases lasting five, ten or in some instances more than a decade are not unusual, and the longest are those where the person has the resources to litigate every point. A parallel and much faster route exists in Europe, where the European Arrest Warrant replaced political decision-making with near-automatic judicial recognition between member states, cutting a process that averaged about a year to a matter of weeks, at the cost of the discretion that the older system built in, which is precisely what its critics object to.

The formal test is legal and the decision is often not. Governments refuse requests to protect their own nationals, to avoid delivering someone to a system they mistrust, or because the relationship with the requesting state is bad, and they grant them for the reverse reasons. Countries without the relevant treaties become known as places to go, and a handful of high-profile figures have spent years in one. Asylum can interact directly with extradition, since a person recognised as a refugee from a particular state generally cannot be returned to it. And where extradition is unavailable or too slow, states have sometimes used substitutes, including deportation on immigration grounds, revocation of a passport, luring a person into a jurisdiction where an arrest can be made, and, at the illegal end, seizure abroad, which courts in different countries have treated inconsistently when the person is later put on trial.

Several mechanisms do related work. An Interpol red notice is not a warrant and does not require any arrest, but is a request to member forces to locate and provisionally detain someone pending a formal request, and it has been criticised for being used by some governments against dissidents, prompting a review process within the organisation. A prisoner transfer agreement moves a convicted person to serve their sentence at home, which is the opposite direction and serves a different purpose. Some states exercise jurisdiction over crimes committed abroad by their own nationals, which lets them prosecute rather than surrender. And a small set of offences, including piracy, torture and genocide, are subject to universal jurisdiction, meaning any state may prosecute regardless of where the act occurred or the nationality of those involved, a principle invoked rarely and with great difficulty.

Handing a suspect to another country rests on treaties rather than any general legal duty, and almost all of them require that the conduct be criminal in both states, that the person be tried only for the offence surrendered for, and that there be no political motive, no torture, no unfair trial and often no death penalty. Many civil law countries refuse to surrender their own nationals at all. Contested cases run for years through appeals, the European Arrest Warrant replaced that with near-automatic recognition between member states, and politics decides at least as much as law.