Introduction
The establishment of the single market is a cornerstone of the European Union, founded upon the principle of the free movement of goods, persons, services, and capital. This principle, however, is not absolute. The Treaty on the Functioning of the European Union (TFEU) and the jurisprudence of the Court of Justice of the European Union (CJEU) recognise that Member States must retain the ability to regulate in the pursuit of legitimate public interests. The central tension lies in balancing the objective of market integration against this national regulatory autonomy. This essay will critically evaluate the extent to which the CJEU's approach to justifications and proportionality gives Member States adequate room to regulate, focusing specifically on the free movement of goods under Article 34 TFEU. This essay will argue that while the Court has developed a framework that appears to grant Member States significant scope to justify restrictive measures, its stringent and often intrusive application of the proportionality principle, particularly the necessity test, prioritises market integration to such a degree that it often fails to provide adequate space for national policy-making.
The Scope of Article 34 and the Rise of Justifications
Article 34 TFEU prohibits ‘quantitative restrictions on imports and all measures having equivalent effect’ (MEQRs) between Member States. The CJEU gave this prohibition an exceptionally broad interpretation in Procureur du Roi v Dassonville (Case 8/74), defining an MEQR as any trading rule capable of hindering, directly or indirectly, actually or potentially, intra-Community trade. This expansive definition captures a vast array of national regulations which, although not designed to discriminate against imports, may nonetheless create barriers to trade. The turning point in the Court’s jurisprudence came in Rewe-Zentral AG v Bundesmonopolverwaltung für Branntwein (Cassis de Dijon) (Case 120/78). In this case, the CJEU established that even indistinctly applicable measures (those applying equally to domestic and imported goods) could be caught by Article 34 TFEU if they created a trade barrier. A German law imposing a minimum alcohol level for liqueurs was found to be an MEQR because it prevented the sale of a French liqueur that was lawfully produced and marketed in France.
Crucially, Cassis de Dijon also established the ‘rule of reason’, acknowledging that such indistinctly applicable measures could be justified if they were necessary to satisfy a set of judicially recognised 'mandatory requirements'. These include objectives such as the effectiveness of fiscal supervision, the protection of public health, the fairness of commercial transactions, and the defence of the consumer. This was a significant development, as it created a parallel, open-ended list of justifications alongside the exhaustive and narrowly interpreted list of public interest grounds in Article 36 TFEU (which includes public morality, public policy, and the protection of health). On the surface, the creation of mandatory requirements seems to provide Member States with considerable flexibility to pursue legitimate policy aims, even if their measures incidentally restrict trade. It signals a judicial acceptance that the creation of a single market does not require a complete deregulation at the national level.
Proportionality: The Real Test of Regulatory Autonomy
Despite the apparent latitude offered by the rule of reason, any justification invoked by a Member State, whether under Article 36 TFEU or the Cassis de Dijon mandatory requirements, is subject to a strict test of proportionality. It is through the application of this principle that the CJEU exercises control over national measures and, it is argued, significantly curtails Member State autonomy. A measure will only be deemed proportionate if it is both suitable to achieve the public interest objective and necessary to do so, meaning there is no less restrictive alternative available (Chalmers et al., 2019). While the suitability test is often straightforward for a Member State to satisfy, the necessity limb has proven to be a major hurdle.
The CJEU's exacting approach can be clearly seen in Commission v Germany (Beer Purity) (Case 178/84). Germany prohibited the marketing of beers containing additives, justifying the rule on grounds of public health and consumer protection. The Court dismissed both arguments as disproportionate. It found the public health argument unconvincing because the additives were permitted in other Member States, suggesting the health risk was not severe enough to warrant an import ban. More importantly, regarding consumer protection, the Court held that German consumers could be adequately protected from confusion by a less restrictive measure: mandatory labelling. By insisting on labelling as the proportionate solution, the Court effectively substituted its own policy judgment for that of the German government. This demonstrates a clear preference for a market access solution over a national standard, suggesting that the 'room to regulate' is conditional on adopting the least trade-restrictive policy imaginable. This approach has been criticised for promoting a negative form of integration, where national rules are dismantled in favour of market access, rather than a positive integration where common EU-wide standards are agreed upon (Weatherill, 2017).
Evaluating the Balance: Market Integration vs. Public Interest
The central question is whether this jurisprudential framework provides an ‘adequate’ balance. It is clear that the CJEU’s primary objective is to police the internal market and prevent Member States from using public interest arguments as a disguised form of protectionism. A strict proportionality test is arguably essential for this task; without it, the prohibitions in Article 34 could be rendered meaningless by a wave of national exceptions. From this perspective, the CJEU is simply performing its function as the constitutional court of the EU, ensuring the primacy of Treaty objectives.
However, the level of scrutiny applied by the Court often appears to go beyond policing protectionism and into the realm of dictating domestic policy. The necessity test, in particular, empowers the Court to question the wisdom of national legislative choices. The Sunday trading cases illustrate this ambiguity. In Torfaen Borough Council v B&Q plc (Case C-145/88), the Court accepted that rules on Sunday opening hours could be justified by reference to socio-cultural objectives, but left the final decision on proportionality to the national court. This suggested a degree of deference, but in practice it resulted in legal uncertainty and further litigation. The jurisprudence implies that if a national objective can be achieved in a manner that is even marginally less restrictive of trade, the Member State is obliged to adopt that alternative, regardless of its domestic political, social, or economic preferences. This puts Member States in the difficult position of having to prove a negative: that no other conceivable policy could achieve their aim with a lesser impact on trade.
This integrationist logic is, however, not absolute. The CJEU has shown that it is willing to countenance significant restrictions on trade when fundamental rights are at stake. In Schmidberger v Austria (Case C-112/00), the Court held that the temporary closure of a major transit route for a political demonstration, which clearly obstructed the free movement of goods, was a justifiable restriction because it was necessary to protect the fundamental rights of freedom of expression and assembly. Similarly, in Omega Spielhallen (Case C-36/02), a German ban on a 'laser-tag' game simulating homicide was justified on the grounds of protecting human dignity, a fundamental principle of the German constitution. These cases suggest that the 'adequacy' of the regulatory space afforded to Member States is not uniform; it expands when core constitutional values or fundamental rights are invoked, as opposed to more general policy goals like consumer protection. However, these cases remain relatively exceptional. The default position of the Court remains one where economic freedoms are given significant weight, and national measures that deviate from a market-oriented logic face intense scrutiny.
Conclusion
In conclusion, the CJEU's framework for justifications and proportionality presents a paradox. On one hand, the development of 'mandatory requirements' in Cassis de Dijon created an open-ended and flexible system for Member States to justify national rules that restrict the free movement of goods. This formally provides a wide scope for regulation in the public interest. On the other hand, this scope is heavily constrained by the Court's rigorous application of the proportionality test. The insistence on the 'least restrictive means' often leads the CJEU to overrule national policy choices in favour of solutions that maximise market access, such as labelling, rather than allowing for different national standards. While this approach is effective at preventing protectionism and fostering a single market, it arguably fails to provide an ‘adequate’ degree of regulatory autonomy for Member States. The balance is tilted in favour of economic integration, and only when non-economic interests rise to the level of fundamental or constitutional rights does the Court consistently show a greater degree of deference. Therefore, while Member States are certainly entitled to regulate, the room provided for them to do so is often narrower than what a democratic government might reasonably require to pursue its legitimate public interests.
References
Chalmers, D., Davies, G. and Monti, G. (2019) European Union Law: Text and Materials. 4th edn. Cambridge: Cambridge University Press.
Commission v Germany (Beer Purity) (Case 178/84) ECLI:EU:C:1987:126.
Procureur du Roi v Dassonville (Case 8/74) ECLI:EU:C:1974:82.
Rewe-Zentral AG v Bundesmonopolverwaltung für Branntwein (Cassis de Dijon) (Case 120/78) ECLI:EU:C:1979:42.
Schmidberger v Austria (Case C-112/00) ECLI:EU:C:2003:333.
Omega Spielhallen- und Automatenaufstellungs-GmbH v Oberbürgermeisterin der Bundesstadt Bonn (Case C-36/02) ECLI:EU:C:2004:614.
Torfaen Borough Council v B&Q plc (Case C-145/88) ECLI:EU:C:1989:593.
Treaty on the Functioning of the European Union (TFEU).
Weatherill, S. (2017) The internal market as a legal concept. Oxford: Oxford University Press.
