Extradition from Spain to Mexico: The 1978 Treaty and Its Two Protocols

The treaty framework with Mexico is the most layered of those Spain maintains in Latin America. The base text is the Treaty on Extradition and Mutual Assistance in Criminal Matters between the Kingdom of Spain and the United Mexican States, signed in Mexico City on 21 November 1978, whose instrument of ratification was published in the BOE of 17 June 1980 and which has been in force since 1 June 1980. Two protocols and a later assistance treaty have since been layered on top. Working from the 1978 text in isolation leads to wrong conclusions on central points.

If You Are Arrested in Spain on a Mexican Request

Arrest normally precedes the formal request. In Spain, Article 8 of Act 4/1985 of 21 March, on Passive Extradition (BOE of 26 March 1985), requires the detainee to be brought before the Central Investigating Court on duty within no more than twenty-four hours. That court does not go into the merits: it verifies identity, informs the person of the request and rules on remand or release with precautionary measures.

From that moment there are two fronts. One is custody. The other is the file: what documents accompany the request, what decision underpins it and whether the conduct, as described, is also an offence in Spain. That check cannot be postponed, because it shapes everything that follows.

A Treaty With Two Protocols on Top

• Treaty of 21 November 1978, published in the BOE of 17 June 1980. Title I contains the general regime of surrender.
• Protocol of 23 June 1995, done in Mexico City and published in the BOE of 7 August 1996, in force since 1 September 1996. It redrafted, among others, Article 4.1 on political offences, Article 6 on tax, customs and exchange-control matters, points b) and d) of Article 15 on supporting documents, and Article 21.3, which sets sixty days for surrender to be carried out once granted.
• Second Protocol of 6 December 1999, done in Mexico City and published in the BOE of 3 April 2001, in force since 1 April 2001. It amended Articles 2, 15, 17.1.a) and 40.1 and inserted a new Article 19 bis.

Alongside these sits the Treaty on Mutual Legal Assistance in Criminal Matters, done at Las Palmas de Gran Canaria on 29 September 2006 and published in the BOE of 31 July 2007, which replaced Title II of the 1978 treaty — the part dealing with assistance — leaving the extradition regime untouched. A layered structure of this kind is not unusual: the framework with the United States also combines a bilateral treaty with later supplementary instruments, as described in our note on extradition to the United States. The inventory of instruments, with links to the official documents, is in our guide to Spain's extradition treaties.

The Penalty Threshold After the Second Protocol

Article 2, as redrafted by the Second Protocol of 1999, provides that extradition lies for conduct punishable under the laws of both parties by a custodial penalty whose maximum is no less than one year. Where enforcement of a sentence is sought, the outstanding portion must be no less than six months.

The bar is low, so the practical argument rarely turns on seriousness. It turns on dual criminality — whether the conduct described in the Mexican file, stripped of its label, amounts to an offence under the Spanish Criminal Code — and on whether criminal liability is still alive, which is checked under both legal systems.

Grounds for Refusal

• Political offences and non-discrimination (Article 4, as redrafted in 1995). Extradition is not granted for offences regarded as political, subject to the exceptions the provision lists, nor where there are substantial grounds for believing that the request seeks to prosecute or punish a person on account of race, religion, nationality or political opinions.
• Nationals (Article 7). Both parties have the power to refuse the extradition of their nationals. In Spain, Article 3 of Act 4/1985 turns that power into a prohibition for Spanish nationals and for foreign nationals whose offences fall within the jurisdiction of the Spanish courts.
• Res judicata (Article 9). Extradition is not granted where the person has already been tried by the authorities of the requested party for the same facts.
• Extinguished liability (Article 10). Limitation or any other ground of extinction bars surrender; the Spanish calculation is made under Article 131 CP.
• Capital punishment (Article 12). Where the offence is punishable by death under the law of the requesting party, extradition is granted only if that party gives assurances that the penalty will not be carried out. Article 4.6 of Act 4/1985 imposes an equivalent requirement in domestic law, extended to penalties impairing bodily integrity or amounting to inhuman or degrading treatment.

The Second Protocol also introduced an allocation rule worth keeping in mind: grounds of opposition raised before the requesting party may not be re-argued in proceedings before the requested party. Defence in the home State and defence in Spain are not interchangeable.

Simplified Surrender Under Article 19 bis

The Second Protocol inserted an Article 19 bis whose effect is easy to overlook. Where the requested person states to the competent authorities of the requested party that he or she consents to being extradited, that party may grant extradition without further formalities and take the measures its laws allow to expedite it — and in those cases the rule of speciality does not apply.

Speciality is the guarantee that prevents a surrendered person from being tried for earlier offences other than those on which the extradition was granted without a supplementary authorisation. In Spanish law it is governed by Article 21 of Act 4/1985, which requires that authorisation to be processed as a fresh extradition request and which lapses if the person, having had the opportunity to leave the territory, remains there for more than forty-five days or returns after leaving. Consenting under Article 19 bis means giving up that protection — a decision that can only be taken with full knowledge of what else is pending in the requesting State.

Provisional Detention Periods

Article 19 of the Treaty governs provisional detention: it may be lifted if the requested party has not received the extradition request within forty-five days, and it may in no case exceed sixty days. Once extradition is granted, Article 21.3, as redrafted in 1995, allows sixty days for surrender to be carried out.

Domestic law runs in parallel: Article 10 of Act 4/1985 lifts provisional custody where forty days pass without a properly filed request, and allows a further forty where one is filed, subject to the ceiling in the Criminal Procedure Act. Identifying which period governs a particular file — and from what date it runs — is one of the first tasks of the defence.

Proceedings Before the National Court

The request is made through diplomatic channels or from Minister of Justice to Minister of Justice (Article 7 of Act 4/1985). The Ministry of Justice submits a reasoned proposal to the Government within eight days and the Government decides within fifteen whether the file continues before the courts (Article 9). If it does, the requested person appears with a lawyer before the Central Investigating Court, which asks whether he or she consents to surrender (Article 12); otherwise the file goes up to the Criminal Chamber of the National Court.

Prosecutor and defence examine the file for three days each (Article 13); the hearing is listed within the following fifteen days (Article 14); the court rules by reasoned order within a non-extendable three days and an appeal by way of súplica lies to the full Criminal Chamber (Article 15). Article 6 marks the decisive asymmetry: a final judicial refusal is definitive, whereas a declaration that extradition is admissible does not bind the Government, which decides on surrender under Article 18.

When a Spanish Court Makes the Request

In the opposite direction, outgoing extradition is governed by Articles 824 to 833 LECrim. It requires a reasoned remand order or a final judgment (Art. 825 LECrim); it lies in the cases provided for in the treaties in force with the State where the person is located (Art. 827 LECrim); it is ordered by reasoned decision of the court hearing the case (Arts. 828 and 829 LECrim); and it is transmitted through the Ministry of Justice, unless the treaty allows a direct request (Art. 831 LECrim).

What to Check in a Mexican File

• Which version applies. Articles 2, 4, 6, 15, 17.1.a) and 21.3 have post-1978 wording: citing the original text is citing a provision no longer in force.
• The Article 15 documents. The 1995 Protocol changed the documentary requirements, and formal scrutiny of the file remains a real ground of opposition.
• Dual criminality for each fact, comparing conduct rather than labels and verifying the one-year threshold.
• Limitation under both systems. Article 10 of the Treaty and Article 4 of Act 4/1985 both allow it to be raised.
• The scope of consent. Before relying on Article 19 bis, weigh what else is pending in the requesting State, because speciality will not protect against it.

Extradition allows no promises of outcome: the framework is set by the treaty and the Act, and the final decision has a judicial stage and an executive one. What does depend on the work done is that each ground is raised while it is still useful. If a request concerns you, you can call us on +34 91 078 65 74 or read our extradition and European Arrest Warrant defence page.