The extradition procedure in Spain is a mixed process, part executive and part judicial, that decides whether a person sought by another State must be surrendered to be tried or to serve a sentence abroad. Passive extradition (the kind that affects someone sought while they are in Spain) is governed by Law 4/1985 of 21 March, except where a treaty Spain has signed provides otherwise (art. 1). Its defining feature is that it runs in three phases with fixed deadlines, and in each one the defence has a specific point at which to act. This article maps those phases and deadlines and applies to the Spanish procedure, not to extradition under UK, US or any other law. If a court in Spain has already convicted you and you are abroad, see what happens when Spain extradites to the UK and other countries.

The three phases: executive, judicial and final executive decision

The most common misconception is to describe extradition as a two-block process, “first the Government, then the judge.” It is not. Law 4/1985 sets out three phases, and the third is decisive because the file goes back to the Government:

Phase	Who decides	What is resolved
1. Initial executive	Council of Ministers, on a proposal from the Ministry of Justice	Whether the request proceeds down the judicial route (art. 9)
2. Judicial	Central Investigating Court and Criminal Chamber of the Audiencia Nacional	Whether surrender is legally appropriate (arts. 12 to 15)
3. Final executive	Council of Ministers	The last word on actual surrender (art. 6)

The point of art. 6 is twofold and worth keeping in mind: a ruling by the Chamber declaring extradition appropriate is not binding on the Government, which may refuse surrender in the exercise of national sovereignty, on reciprocity grounds or for reasons of security, public order or Spain’s essential interests. But the rule works in one direction only: if the Chamber refuses extradition, the Government cannot grant it. A favourable judicial ruling is a necessary condition, not a sufficient one; a judicial refusal is final.

How it begins: arrest and the first hours

The procedure usually starts with an arrest, often triggered by an international arrest warrant circulated through Interpol (a red notice). From there, the first hours shape the whole defence.

Provisional arrest and the 24-hour rule

Where the requesting State asks for an urgent provisional arrest, the person must be brought before the Central Investigating Court of the Audiencia Nacional within no more than 24 hours (art. 8). The judge may order provisional detention or, instead, less restrictive measures that the law itself lists: home surveillance, an order not to leave a given place without the judge’s authorisation, periodic reporting to a designated authority, surrender of the passport and the posting of bail (art. 8). Asking for one of these alternatives to detention is the defence’s first move.

The 40-day deadline for the formal request

Provisional arrest is not open-ended. If 40 days pass without the requesting country having duly filed the extradition request, the arrest is lifted (art. 8). If the request does arrive within those 40 days, the period is extended by a further 40 days so that the Ministry of Justice and the Government can process it (art. 10). Each deadline is a defence opportunity: once the period lapses without a valid request, release should be sought.

Initial executive phase: the Government’s decision to proceed

Once the formal request is received through diplomatic channels or directly between Ministers of Justice (art. 7), the first executive phase opens. The deadlines are fixed in art. 9, and they settle a common question about “how long the Government has”:

• The Ministry of Justice has a maximum of 8 days, from the day after receipt of the request, to submit a reasoned proposal to the Government.
• The Government (Council of Ministers) takes its decision within the 15 days following that proposal.
• If those 15 days pass without a decision, the Ministry of Justice decides on the Government’s behalf within the next 3 days.

So it is not “8 days” on its own: it is 8 days for the Ministry plus 15 for the Government. In this phase the Government weighs reciprocity and expediency, which matters most where there is no treaty and surrender depends on case-by-case cooperation, as happens with countries that have no full extradition treaty with Spain. If the Government decides not to proceed, the requesting State is notified and the person, if detained, is released.

Judicial phase before the Audiencia Nacional

If the Government decides to proceed, the file passes to the Central Investigating Court and then to the Criminal Chamber of the Audiencia Nacional. This is the heart of the procedure and where the defence is concentrated.

The first appearance and consent to surrender

The Central Investigating Judge orders the person’s immediate appearance, assisted by a lawyer and, where needed, an interpreter, with the public prosecutor always summoned (art. 12). At that appearance the judge asks the person, with their reasons, whether they consent to extradition or intend to oppose it:

• If they consent and there are no legal obstacles, the procedure can be resolved in a simplified way and surrender granted without a hearing.
• If they oppose it, the judge rules on their situation (release on conditions or detention) and refers the case to the Criminal Chamber.

The decisions at this appearance take the form of an “auto” (a reasoned order), issued within the following 24 hours (art. 12). Whether or not to consent is a strategic decision best taken with advice: consent speeds up surrender and, once given, it shapes the rest of the process.

The instruction phase and the hearing

If the person opposes surrender, a written phase opens: the file is disclosed to the prosecutor and the defence lawyer for a successive period of three days for submissions (art. 13). The court registry then sets the hearing (vista), held within the 15 days following the instruction period, with the prosecutor, the person sought (assisted by an interpreter if needed) and the defence lawyer (art. 14). At the hearing only evidence relating to the conditions the law requires for extradition is admissible. This is where the defence makes its case: lack of dual criminality, limitation, double jeopardy or risk that rights will be violated in the requesting country.

The Chamber’s ruling

After the hearing, the Court rules by reasoned order (auto) within a non-extendable period of three days, deciding whether extradition is appropriate (art. 15). The only appeal against that order is a recurso de súplica before the full Criminal Chamber of the Audiencia Nacional, decided by judges other than those who issued the order under appeal (art. 15).

EAW or classic extradition: which applies

Not everything is “extradition” in the strict sense. Between EU Member States, surrender does not go through Law 4/1985 but through the European Arrest Warrant (EAW), a faster and fully judicial mechanism in which the Government barely intervenes. Classic extradition under Law 4/1985 is reserved for non-EU countries, with or without a treaty. If your case has a European element, it is worth understanding how the EAW and a Spanish extradition order work, because the deadlines and safeguards differ.

Requirements: dual criminality, seriousness and a judicial decision

For extradition to succeed, several substantive conditions must be met:

• Dual criminality. The act must be an offence in both the requesting country and Spain.
• Minimum seriousness. The law only allows extradition for acts punishable by a custodial penalty of at least one year at its maximum (or a heavier penalty); where surrender is sought to serve a sentence, it must be no less than four months of imprisonment (art. 2).
• A judicial decision behind the request. A conviction or a committal-and-detention order, with the identification of the person sought and copies of the applicable legal texts (art. 7).

The speciality principle also applies: the person surrendered may only be tried for the acts that prompted the extradition.

Grounds for refusal: mandatory and optional

Law 4/1985 distinguishes between grounds that require refusal and grounds that allow it. The distinction is practical: with a mandatory ground, surrender cannot proceed; with an optional one, there is a margin of appraisal the defence must work on.

Mandatory grounds (art. 4: “shall not be granted”):

• Political offences, with acts of terrorism not treated as such.
• Military offences under Spanish law and those committed through the media in the exercise of free expression.
• Where the person is to be tried by an exceptional court.
• Where criminal liability has been extinguished under Spanish or the requesting State’s law (for example, by limitation).
• Where the person has already been tried, or is being tried, in Spain for the same acts (double jeopardy / lis pendens).
• Where the requesting State does not guarantee that the person will not be executed or subjected to penalties harmful to their bodily integrity or to inhuman or degrading treatment.
• Where the guarantees required by article 2 are not given.
• Where the person has been recognised as a refugee.

In addition, Spain does not extradite Spanish nationals, nor foreigners for offences within the jurisdiction of the Spanish courts (art. 3).

Optional grounds (art. 5: “may be refused”):

• Where there are grounds to believe the request has been made to prosecute or punish the person for their race, religion, nationality or political opinions, or that their situation may be aggravated by such considerations.
• Where the person sought is under 18 with habitual residence in Spain and extradition may harm their social reintegration.

How to appeal an extradition decision

The defence does not end with the Chamber’s order. That order can be appealed by recurso de súplica before the full Criminal Chamber of the Audiencia Nacional (art. 15). Once the domestic judicial route is exhausted, where a fundamental right is at stake an amparo before the Constitutional Court is available and, where appropriate, an application to the European Court of Human Rights, which can order interim measures to suspend a surrender where there is a serious risk to the person’s life or integrity. Bear in mind that the final executive phase (art. 6) stays open until the last moment: even with an order favourable to surrender, the Government can refuse it.

How it looks in practice: known cases

Extradition involving countries without a full treaty with Spain has drawn media attention in cases such as Artur Segarra (in the framework of cooperation with Thailand) or the debate around Daniel Sancho. They illustrate what matters most in these cases: whether a treaty exists, dual criminality and the safeguards the requesting country offers.

A practical example

Consider an illustrative case. A person is arrested in Barcelona following a red notice and brought before the Central Investigating Court within 24 hours. The judge orders provisional detention, but the lawyer asks for release with surrender of the passport and bail. The requesting country files the formal request on day 38, within the 40-day period, so detention is extended. At the first appearance the person opposes surrender, and at the hearing the defence shows that the act is time-barred under Spanish law. The Chamber refuses extradition by reasoned order and, under art. 6, the Government can no longer grant surrender. It is a hypothetical example, but it shows how each phase and each deadline opens a way to act.

Frequently asked questions

How long does an extradition procedure in Spain take?

It depends on the case and, above all, on whether the person consents. If they consent and there are no obstacles, it can be resolved in a simplified way at the first appearance. If they oppose it, the written phase and the hearing lengthen the process, and appeals lengthen it further. Provisional arrest has a cap tied to the initial 40 days and its 40-day extension (arts. 8 and 10).

How long does the Government have to decide?

The Ministry of Justice has 8 days to submit its proposal and the Government has 15 days to decide from that proposal; if it does not, the Ministry decides on its behalf within 3 days (art. 9).

Will I be held in custody during the process?

Possibly. The Central Investigating Court may order provisional detention, but also less restrictive measures such as periodic reporting, surrender of the passport or bail (art. 8). Asking for an alternative to detention is one of the defence’s first moves.

Can I oppose surrender, or is it better to consent?

At the first appearance you can consent to extradition or try to oppose it (art. 12). Consenting speeds up surrender; opposing opens the full judicial phase. It is a strategic decision to weigh with a lawyer, because it shapes everything that follows.

What is the difference between the EAW and extradition?

The EAW is the surrender mechanism within the European Union, faster and judicial, with minimal Government involvement. Classic extradition under Law 4/1985 applies to non-EU countries.

On what grounds can extradition be refused?

On mandatory grounds (a political offence, risk of the death penalty or inhuman treatment, double jeopardy, limitation, refugee status, Spanish nationality, among others) and on optional grounds (persecution for race, religion or opinions, or minors resident in Spain). Each ground opens a distinct line of defence (arts. 3 to 5).

Can I take my case to the European Court of Human Rights?

Yes. Once the domestic route is exhausted (súplica before the full Chamber and, where appropriate, amparo before the Constitutional Court), you can apply to the European Court of Human Rights, which can order interim measures to suspend a surrender that puts fundamental rights at risk.

If you face an extradition procedure in Spain, every deadline counts: speak to a criminal lawyer in Spain as early as possible.

Official source: Law 4/1985 of 21 March on Passive Extradition (BOE).