## Facts

- The President of the Republic referred the Treaty on European Union (signed Feb. 7, 1992) to the French Constitutional Council for preventive constitutional review before ratification.
- The referral asked whether, given France’s commitments and implementation conditions, ratification required a prior constitutional revision.
- The treaty established the European Union and provided for, among other changes, Economic and Monetary Union (including an independent European Central Bank), Union citizenship, and voting/eligibility rights for EU citizens residing in another Member State.
- The Council reviewed treaty provisions affecting sovereign competences (especially monetary policy), the status and rights of citizens, and the relationship between French constitutional authorities and EU institutions.
- The proceeding was not a dispute between private parties; it was an institutional review of an international agreement’s constitutionality.

## Issues

1. Whether treaty-based transfers of competences—particularly monetary policy—were compatible with constitutional limits protecting the essential conditions for exercising national sovereignty.
2. Whether Union citizenship provisions granting non-nationals voting and candidacy rights in municipal (and related European Parliament) elections in France were compatible with constitutional rules tying the electorate to French nationality.
3. Whether the treaty could be ratified under the existing Constitution or instead required a constitutional amendment as a precondition to ratification.

## Decision

- The Council held the treaty partially incompatible with the Constitution and ruled that constitutional revision was required before ratification could be authorized.
- It found that the Economic and Monetary Union provisions entailed a transfer of powers in an area constituting an essential attribute of national sovereignty (monetary sovereignty), exceeding what the Constitution then allowed without amendment.
- It held that granting EU citizens who were not French nationals the right to vote and stand in municipal elections in France conflicted with constitutional provisions defining the electorate by nationality, thereby affecting essential conditions of national sovereignty.
- It concluded that other cooperation mechanisms, including aspects of foreign and security policy framed as intergovernmental cooperation subject to Member State control, did not by themselves compel constitutional revision on the same basis as the monetary and municipal voting provisions.

## Legal Principles

- A constitution may permit participation in a permanent international organization with decision-making powers and agreed transfers of competences, but only within limits that preserve the essential conditions for exercising national sovereignty.
- When an international agreement affects essential attributes of sovereignty (including core sovereign competences such as monetary policy), ratification authorization must be preceded by constitutional amendment.
- Constitutional rules defining the “people” and the electorate may bar extending local electoral rights to non-nationals absent explicit constitutional authorization.
- Preventive constitutional review of treaties functions as an ex ante control: incompatibility triggers an obligation to amend the Constitution before ratification can proceed.

## Conclusion

The Council permitted European integration in principle but ruled that the Maastricht Treaty could not be ratified under the Constitution as then written because key provisions—especially monetary union and municipal voting rights for EU non-nationals—required prior constitutional authorization through amendment.


Maastricht I Decision, No. 92-308 DC (Fr. Const. Council Apr. 9, 1992)