Constitutional Control of International Treaties in Spain

Constitutional Control of International Treaties

The Spanish Constitution (EC) is our basic internal standard. Treaties are subject to the control of constitutionality, just as all major sources of our domestic law are.

Procedures and Consequences of Legal Challenges

Who can impugn these treaties, and what are the consequences? Control is prospective; if the sentence confirms constitutionality, there is no issue. However, if it is found unconstitutional, specific measures must be taken. The control must be:

Prior Constitutional Control Under Article 95

• Previous Control: This occurs before the treaty can produce legal effects. Article 95 of the EC states: "1. The conclusion of an international treaty containing stipulations contrary to the Constitution shall require a prior constitutional amendment. 2. The Government or either House may request the Constitutional Court to declare whether or not such a contradiction exists."

This particular prior checking serves as a verification within our legal system. It results in a formal statement from the Court. The treaty in question is taken to the Constitutional Court (TC) upon request by the Government or either House. Legitimation is exclusive to these organs. If there are any doubts regarding constitutionality during the conduct of the treaty, the matter must be referred to the Court.

Timing and Validity of the Constitutional Query

The timing of the trial is important. When is the query adequate to address the Court? It should not be at an early stage, nor at the very final moment. The TC advises performing this once the text is finalized but still without formal consent, as it has not yet been ratified. The request must be made by legitimate constitutional bodies.

Legal Effects of the Court's Declaration

The Court's statement does not dictate a standard sentence because the treaty is not yet a legal rule; since the State has not yet given consent, we are dealing with a project or text that has been set but lacks formal ratification. Is this declaration binding? Yes, it obliges the State.

State Options Following Unconstitutionality

What can the State do following a declaration of unconstitutionality regarding an international treaty?

• Change the EC: Amend the Constitution to accommodate the treaty.
• Modification of the treaty: Adapt the text to the Constitution, which requires entering a new negotiation phase.
• Withdrawal: Resignation from concluding the treaty under the proposed terms.
• Partial approval: The introduction of reservations. We conclude the treaty while excluding parts that contradict the EC. Note that not all treaties allow for reservations.

Modifying the EC poses significant domestic problems. To avoid this, constitutional reform should be the last resort; one must first try to negotiate the text, enter reservations, or withdraw.

Posterior Control and International Responsibility

• Posterior Control: This refers to future control once a treaty is filed with the Court via constitutional challenges. The procedure ends in a binding ruling. If no problem is found, the effects are dismissed. However, if the sentence is estimatory and finds the treaty unconstitutional, it poses a difficult dilemma: What effects should the Court's decision have? The treaty is contrary to the EC, but it is already ratified and binding upon the Spanish State. The alternatives are:
  • Ignoring the internal decision (which is not possible).
  • Ignoring the treaty, which leads to international responsibility.