Hard Concepts in Law · European Union
The hardest concepts in European Union law
20 ideas, 7 areas of law, one picture for each.
These are the ideas that students find hard, across 7 areas of law. Each one has its own page with an everyday picture of how the rule is built, the usual mistakes, a worked example and a trap question.
Step 1Institutional law
Conferral of powers and the categories of competence
The housekeeper with a signed errand list
The Union has only the powers the Member States have conferred on it in the Treaties, so every Union act needs a Treaty basis, and powers not conferred stay with the Member States. The Treaties sort the Union’s powers into categories, mainly exclusive, shared and supporting, and the category decides how much room the Member States keep.
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Step 2Institutional law
Subsidiarity and proportionality
The plumber and the right-sized wrench
In areas that are not exclusively its own, the Union may act only if the objective cannot be sufficiently achieved by the Member States and can be better achieved at Union level; that is subsidiarity. Proportionality requires that the content and form of any Union action go no further than is necessary to achieve the Treaty objectives.
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Step 3Institutional law
Implied external powers
The steward and the outside contractor
The Union may conclude international agreements not only where the Treaties expressly say so but also where this is necessary to achieve a Treaty objective, or where the matter is already covered by common rules that the agreement could affect. When the Union acquires such a power in an area, the Member States may lose their own right to commit themselves to third countries on that subject.
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Step 4Sources of law
Regulations, directives and decisions
The blueprint, the brief and the letter
A regulation applies directly in every Member State without national implementation, a directive binds the Member States as to the result and leaves them to choose how to achieve it, and a decision binds those to whom it is addressed. Recommendations and opinions have no binding force, although courts may take them into account.
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Step 5Internal market
Harmonisation and the internal market
The universal socket and the travel adapter
The internal market is an area without internal frontiers in which goods, persons, services and capital move freely, and the Union may approximate national laws to build it. Harmonisation is not a general power to regulate, and the Union may use it only where a measure genuinely helps the market function, by removing obstacles or appreciable distortions of competition.
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Step 6Union law in national courts
Direct effect
The cinema ticket in your own hand
A provision of Union law has direct effect when it gives individuals rights that they can invoke before their own national courts, without waiting for the Member State to pass a law. The Court of Justice established the idea in its case law, and the usual conditions are that the provision is clear, precise and unconditional.
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Step 7Union law in national courts
Vertical and horizontal effect of directives
The postcard addressed to the town hall
A directive that has direct effect can be relied on against the Member State and its public bodies, which is vertical effect, but the Court has held that a directive cannot of itself impose obligations on private parties, so it lacks horizontal effect. The reason is that a directive is addressed to the Member States, which alone are bound to transpose it.
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Step 8Union law in national courts
Supremacy and national constitutional courts
The league rulebook and the club charter
Where a rule of Union law conflicts with a rule of national law, the Court of Justice holds that the Union rule prevails and that national courts must set the national rule aside in the case before them. Some national constitutional courts accept this with reservations of their own, so supremacy is declared by the Court of Justice but its limits are still debated.
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Step 9Union law in national courts
Indirect effect and conforming interpretation
The tailor’s alterations
National courts must interpret national law, as far as they can, in the light of the wording and purpose of Union law, especially directives, so as to achieve the result the directive requires. The duty applies to all national law, whenever made, but it stops short of reading the national text in a way that contradicts it.
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Step 10Union law in national courts
State liability for breach of Union law
The warranty on a roof
A Member State must compensate individuals for loss caused by its serious breaches of Union law, whether by failing to implement a directive or by passing contrary legislation. The Court of Justice created the principle in its case law, and national courts decide the claims, using national rules on damages within limits set by Union law.
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Step 11Union courts and procedure
The preliminary reference procedure
The family doctor and the specialist’s opinion
A national court may, and a court of last instance generally must, ask the Court of Justice to rule on the interpretation of Union law or the validity of a Union act when that is necessary to decide the case before it. The Court of Justice answers the question of Union law, and the national court then applies the answer and decides the dispute.
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Step 12Union courts and procedure
Infringement proceedings
The warning letters before the fine
The Commission, as guardian of the Treaties, may bring a Member State before the Court of Justice for failing to fulfil its obligations under Union law, after a pre-litigation stage in which the State may respond. If the State does not comply with the Court’s judgment, a second round can end in a lump sum or penalty payment.
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Step 13Union courts and procedure
Annulment actions and standing
The guest list drawn before the party
Under the annulment action the Court reviews the legality of Union acts, and a person who is not the addressee of an act can challenge it directly only if it is of direct and individual concern to them. The usual formulation of individual concern, the Plaumann test, is demanding, so the route through national courts and preliminary references matters.
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Step 14Union law in national courts
Effectiveness, equivalence and national procedural autonomy
The lodger’s house rules
Where Union law does not lay down the procedure, each Member State decides the courts, time limits and rules for enforcing Union rights, but those rules must be no less favourable than for similar domestic claims and must not make enforcement practically impossible or excessively difficult. This is the case-law pair of equivalence and effectiveness.
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Step 15Fundamental rights
General principles of Union law and the Charter of Fundamental Rights
The foundations beneath the floorboards
Fundamental rights in the Union come from two linked sources: the general principles of Union law developed by the Court of Justice, and the Charter of Fundamental Rights, which has the same legal value as the Treaties. The Charter binds the Union’s institutions, and it binds the Member States only when they are implementing Union law.
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Step 16Fundamental rights
The EU and the European Convention on Human Rights
Two passports, two border posts
The European Convention on Human Rights belongs to the Council of Europe and is enforced by the European Court of Human Rights in Strasbourg, while the Union is a different organisation with its own Court of Justice in Luxembourg. The Treaties require the Union to accede to the Convention, and until it does so the Convention guides Union law without being formally part of it.
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Step 17Internal market
Free movement of goods
The baker’s van crossing the county line
Member States may not impose customs duties or charges of equivalent effect on trade between them, nor quantitative restrictions or measures having equivalent effect on imports and exports. Such a measure may be justified by an express public-interest ground in the Treaty, or by a mandatory requirement, if it is non-discriminatory and proportionate.
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Step 18Internal market
Free movement of workers and Union citizenship
The commuter’s pass that became a resident’s card
Workers who are nationals of a Member State have the right to take up work in another Member State on the same terms as its own nationals, and Union citizenship builds on that to give nationals of every Member State a right to move and reside, subject to limits. “Worker” is a Union concept, and the exceptions are read narrowly.
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Step 19Internal market
Freedom of establishment and freedom to provide services
The shopfront and the travelling stall
Freedom of establishment lets a person or company set up and carry on a business on a stable and continuous basis in another Member State, while freedom to provide services covers temporary cross-border activity. The line between them matters because different rules and different host-State conditions apply.
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Step 20Competition law
Competition law: agreements and dominant positions
The only well in the village
Union competition law prohibits agreements between undertakings that restrict competition and affect trade between Member States, and it prohibits the abuse of a dominant position. Being dominant is not unlawful in itself, and “undertaking” means any entity engaged in economic activity, whatever its legal form.
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Read this first
EU law is made by the Union’s institutions under powers that the Member States have conferred on it in the Treaties, and it is applied by national courts and the Court of Justice together. The national law of each Member State still governs most of private and criminal law. Each page says whether the idea comes from the Treaties, from regulations and directives, or from the Court of Justice’s case law. Each page states the usual formulation of the rule and names landmark decisions; check the primary sources, and the law of your own Member State, before relying on any rule.
These pages are educational overviews. They are not legal advice and not a substitute for the primary sources.