CITIZENSHIP of the EU is established in Article 20 of the Treaty on the Functioning of the European Union (TFEU). All citizens derive various rights from this status, although the scope of certain rights may vary depending on whether the citizen is engaged in economic activity. Paramount among the rights conferred by the status of citizenship is the right to move to and reside in any Member State (Art. 21 TFEU), under the conditions set out in the Treaty and in the secondary legislation (Directive 2004/38/EC OJ [2004] L 158/77, the Citizens' Rights Directive). Crucially, the right of residence granted by Article 21 TFEU brings with it other benefits, such as being able to secure derivative rights of residence for the citizen's spouse and dependents. In situations where the citizen is a dependent child, Article 21 TFEU may also grant a derivative right of residence to their caregiver when the latter is not an EU citizen (C-00/02 Chen [2004] E.C.R. I-9925). Traditionally, however, a cross-border element is necessary for all these rights to be triggered: in the typical scenario, the citizen moves first to a different Member State, and is then able to exercise the rights that derive from Article 21 TFEU. In the absence of a cross-border element that triggers the application of EU law, the orthodox approach would be to consider the situation a wholly internal one, to be regulated by national law.

The validity of this orthodox approach was questioned after the Court of Justice delivered its decision in Ruiz Zambrano (Case C-34/09, Judgment of 8 March 2011, not yet reported, noted [2011] C.L.J. 309). In this case, the Court considered that a situation lacking the necessary EU cross-border element was, all the same, within the scope of EU law. The decision concerned Belgian children that had never left their country. Despite this, the children were able to rely on the Treaties to derive a right of residence and a right to work for their Colombian father. The Court decided that this wholly internal situation fell nevertheless within the scope of EU law because Article 20 TFEU, the general provision that establishes citizenship, precludes any national measures that would threaten “the genuine enjoyment of the substance of the rights conferred by virtue of that status”, at [42].

It seemed, then, that certain wholly internal situations would be brought within the scope of EU law because the threat to citizenship was too great: they concerned the status of citizen itself (C-135/08 Rottmann [2010] E.C.R. I-1449) or the genuine enjoyment of the substance of the rights conferred by this status (Ruiz Zambrano). The question remained what exactly this “genuine enjoyment of the substance” of citizenship rights entailed; or, in other words, how broad the Ruiz Zambrano exception was. The Court of Justice has had occasion to consider this in two recent cases, McCarthy and Dereci.

In McCarthy (Case C-434/09, Judgment of 5 May 2011, not yet reported), a dual UK and Irish national who had not left the UK sought to rely on EU law in order to secure a right of residence for her Jamaican husband. The Court held that McCarthy was not within the scope of Article 21 TFEU (right of movement and residence) when residing in her own country, clarifying that this provision continues to require a cross-border element. The fact that McCarthy had recently acquired Irish nationality in addition to her UK one was not enough in this respect. The question was then whether she could be brought within the scope of Article 20 TFEU; this was dependent on whether it could be shown that, otherwise, the genuine enjoyment of the substance of her citizenship rights would be threatened. Ultimately, the Court decided that this was not the case since, unlike the Ruiz Zambrano children, McCarthy would not be forced to leave the territory of the Union if she were deemed outside the scope of EU law.

In Dereci (Case C-256/11, Judgment of 15 November 2011, not yet reported), the question was whether several Austrian citizens, who had not exercised their right to free movement, could rely on EU law in order to obtain a right of residence for their relatives. The Court adopted the same position as in McCarthy, further clarifying that the Ruiz Zambrano exception “refers to situations in which the Union citizen has, in fact, to leave not only the territory of the Member State of which he is a national but also the territory of the Union as a whole”, at [66]. Whether this would be the case in the particular situation at stake is, ultimately, for the national court to assess; but the fact that family reunification may appear “desirable to a national of a Member State, for economic reasons or in order to keep his family together in the territory of the Union”, at [68], is not enough in itself to bring an otherwise internal situation within the scope of EU law.

The Ruiz Zambrano exception, then, appears to be very narrow: the citizen needs to prove that he or she will be forced to leave the territory of the Union as a whole. “Being forced” to leave the Union is interpreted so strictly that, for the purposes of family reunification, it seems limited to cases of absolute dependence of the citizen on a third country national, the relationship between child and caregiver being the typical example. The need to leave the Union was indeed assumed by the Court in Ruiz Zambrano: some might argue that the children could have perhaps moved to another Member State instead, taking their family with them (relying on Article 21 TFEU and extending the scope of Chen by relying on Article 8 ECHR). The Court nevertheless chose a much more certain and immediate solution, perhaps because children were involved. By contrast, in McCarthy and Dereci, the Court seems to assume that the citizens involved, who are adults or have at least one parent who is also a citizen, can feasibly remain within their own Member State, and have the possibility to move to another Member State if they want to bring themselves within the scope of EU law in order to secure an EU right of residence for their relatives. Rightly or wrongly, their situation is thus considered not as dire, and this is where the Court chooses to draw the line.

Ultimately, the Court has made it clear that, significant as the Ruiz Zambrano judgment was, it is likely to remain an exception, at least for the moment. The Court reiterated in McCarthy that EU citizens do not derive a right to reside in their own country from Article 21 TFEU; this provision continues to require a cross-border element. Consequently, the default will be that, if a citizen has not exercised her freedom of movement, she is outside the scope of EU law for the purposes of this discussion—the label of “wholly internal situation” continues to apply. Because of Article 20 TFEU, that label will be scrapped in those extreme cases where there is a threat to the core of citizenship (“the genuine enjoyment of the substance” of the rights conferred by citizenship). This core is, however, very limited for the time being. Until now, the Court has interpreted it to include protection from losing the status of citizen itself (Rottmann) and from having to leave the territory of the Union (Ruiz Zambrano), as well as, possibly, protection from national rules governing surnames (Cases C-148/02 Garcia Avello [2003] E.C.R. I-11613; C-353/06 Grunkin and Paul [2008] E.C.R. I-7639, as interpreted in McCarthy).

Regardless of whether the distinction between Ruiz Zambrano, on the one hand, and McCarthy and Dereci, on the other, is justified and workable, it is not surprising that, at least for now, the Court has adopted a cautious approach in deciding what constitutes this core of citizenship that allows the Court to pierce the veil of a wholly internal situation. A wider interpretation would have dramatic effects on the equilibrium of powers between the Union and the Member States. This cautious approach is also apparent from the Court's efforts to avoid potential concerns as to the widening scope of EU fundamental rights standards by not using the latter to justify the existence of a special core of citizenship rights and its consequences, or in order to define its scope. Nonetheless, for all the Court's justified caution, the fact remains that a seed has been planted—and that its future is still uncertain.