the immediately subsequent paragraph that the Member States have limited their
sovereign rights.
Under (2) follows the decision for which the case has become famous: states
cannot override the law of the treaty by means of later national legislation. If they
could, the resulting law might vary from Member State to Member State and the
obligations undertaken through the treaty would become conditional on not being
derogated from by a later national law.
10.6.5 Subsidiarity and the Requirement of Legal Basis
In theVan Gend & LoosandCosta/ENELcases, the CJEU claimed solid ground for
EU law as a legal order in itself, the rules of which apply directly in the Member
States and override the national rules. This went together with strong claims
concerning the sovereignty that the Member States would have transferred to the
EU (the EEC).
Where the CJEU strongly pulled the Union into the direction of supranationality,
the Member States have sometimes been reluctant to follow. The EU may have
powers that prevail over those of the Member States but only in those fields in
which the Member States have transferred those powers to the EU. If the EU is to
perform juridical acts and change the legal positions of the Member States and their
nationals, it must, like all other legal agents, have received the appropriate compe-
tence. By limiting this competence, the Member States can limit the powers of the
EU institutions and try to control the transfer of sovereignty from the Member
States to the EU.
The limitations of the powers of EU institutions take the shape of two demands
on the exercise of these powers that were imposed on the EU in the treaties:
- powers can only be exercised within the limits of the competences conferred
upon the Union (Article 3, Section 6 TEU), - the use of these competences is governed by the principles of subsidiarity and
proportionality (Article 5, Section 1 TEU).
Legality This means that the EU has only those competences that were attributed
to it, and no other. This is essentially the principle oflegality, which holds in
general in public law. In its application to the EU, it is sometimes called the demand
of a legal basis.
Subsidiarity Moreover, the EU should only use its powers where it can perform a
task better than the Member States could do themselves. For example, the EU
should only limit the use of alcohol if a central regulation is better than national
regulations. This is the principle of subsidiarity.
Proportionality Moreover, the EU should only act if the
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