SOLIDARITY IN THE LEGAL ORDER OF THE EUROPEAN UNION

PREFACE 

INTRODUCTORY NOTE 

LIST OF ABBREVIATIONS

INTRODUCTION 1

PART I

«STANDING BY»: SOLIDARITY AS A STRUCTURAL
CONCEPT OF THE EU LEGAL ORDER

CHAPTER A

SOLIDARITY AS AN EXISTENTIAL CONCEPT SHAPING
THE RELATIONS BETWEEN EU ACTORS

Paragraph 1. Solidarity as an unwritten concept and its recognition in the case law of the Court of Justice 17

a. The jurisprudential recognition of solidarity before
the Lisbon Treaty 18

b. The jurisprudential confirmation of solidarity after
the Lisbon Treaty 27

Paragraph 2. The relationship between solidarity and other structural concepts of the European Union legal order 34

a. Solidarity and loyalty 34

b. Solidarity and mutual trust 39

CHAPTER B

SOLIDARITY AS A SOURCE OF OBLIGATIONS FOR EU ACTORS

Paragraph 1. The horizontal dimension: general
solidarity obligations across the Union’s and the Member
States’ legal orders 46

a. Solidarity among the values and objectives
of the European Union 46

i. Solidarity among the values of the EU 46

ii. Solidarity among the objectives of the EU 50

b. Solidarity in the Charter of Fundamental Rights of the European Union 53

Paragraph 2. The vertical dimension: solidarity obligations in specific areas of EU law 56

a. Solidarity obligations in the field of the Common Foreign
and Security Policy 57

b. Solidarity obligations in the Area of Freedom,
Security and Justice 64

i. Solidarity in EU primary law 64

ii. Solidarity in EU secondary law 71

(a) The current legal framework 71

(b) The future legal framework 82

c. Solidarity obligations in the field of energy policy 92

d. Solidarity in the field of cohesion policy 104

Conclusions of Part I 113

PART II

«BEING THERE»: SOLIDARITY AS A RESPONSE
TO SITUATIONS OF CRISIS

CHAPTER A

SOLIDARITY MECHANISMS PROVIDED
FOR IN EU PRIMARY LAW FOR ADDRESSING CRISES

Paragraph 1. The emergency solidarity clauses
in the field of external action 118

a. The «Solidarity clause» of article 222 TFEU 118

b. The obligation of assistance in the field of the Common
Security and Defence Policy (article 42(7) TEU) 123

Paragraph 2. Solidarity measures addressing emergency
situations in the field of asylum and migration 126

a. Dealing with emergencies under article 78(3) TFEU 126

b. Dealing with emergencies under the New Pact:
The Crisis and Force Majeure Regulation 133

Paragraph 3. Solidarity between Member States
in the event of a crisis in the field of energy 136

Paragraph 4. The establishment of an emergency
support instrument 143

CHAPTER Β

NEW SOLIDARITY MECHANISMS SET UP IN RESPONSE
TO EXCEPTIONAL SITUATIONS

Paragraph 1. Solidarity responses to the crisis
in the EMU area 146

a. The institutional asymmetry of the EMU and the limited
role of solidarity 146

b. What is the role of solidarity in the EMU after
the financial crisis? 152

Paragraph 2. Solidarity responses to the Covid-19 pandemic 160

a. Unilateral responses to the pandemic as factors eroding
solidarity 162

b. Coordinated responses to the pandemic as factors enhancing solidarity 167

i. The expansion and activation of the rescEU mechanism 168

ii. The joint procurement of medical equipment and vaccines 169

iii. The emergence of genuine financial solidarity:
Next Generation EU 173

Conclusions of Part II 188

GENERAL CONCLUSIONS 189

BIBILIOGRAPHY 193

TABLE OF CASES (in chronological order) 207

INDEX 213

INTRODUCTION

What does the word «solidarity» mean in everyday language? Is there a common understanding of its content and main features in different fields such as philosophy, political science, social theory or law? How does it differ from similar concepts such as cooperation, altruism, benevolence, assistance or fellow-feeling? These initial questions are important when trying to approach the concept and role of solidarity within a legal order such as that of the European Union. Indeed, the use of this notion in different contexts and circumstances has eroded its normative content, transforming it into a rather fluid and elusive concept of a «multi- and cross-disciplinary» nature.

Solidarity is defined in the Oxford Dictionary as «support by one person or group of people for another because they share feelings, opinions, aims etc.». The French Robert Dictionary describes solidarity as «relation entre personnes qui entraîne une obligation morale d'assistance mutuelle», and the Larousse Dictionary refers to a «rapport existant entre des personnes qui, ayant une communauté d’intérêts, sont liées les unes aux autres» or to a «sentiment d’un devoir moral envers les autres membres d’un groupe, fondé sur l’identité de

situation, d’intérêts». Similarly, according to the Italian Treccani dictionary the meaning of solidarity is «rapporto di fratellanza e di reciproco sostegno che collega i singoli componenti di una collettività nel sentimento appunto di questa loro appartenenza a una società medesima e nella coscienza dei comuni interessi e delle comuni finalità». In German, solidarity is defined as «unbedingtes Zusammenhalten mit jemandem aufgrund gleicher Anschauungen und Ziele».

These definitions are not identical, but they highlight several essential elements that characterise the notion of solidarity: firstly, they refer to the existence of common interests or objectives within a group of people, which create a special bond and a sense of belonging to a community. This seems to be a key point in the attempt to understand the content of this concept, all the more that solidarity has emerged as a key concept in social theory; for example, Durkheim identified it as an important component for the functioning of societies and described two types thereof: mechanical solidarity, which is based on the similarity of people in homogeneous societies, and organic solidarity, which prevails in more advanced societies where people have different roles and interact with each other. On the other hand, Weber approached solidarity as a type of social relationship established by the organising power of a polity,.

Moreover, the special bond resulting from the community of interests or aims entails a common willingness of the group members to support each other, in other words the «preparedness to share resources with others, readiness for collective action and will to institutionalise it through the

establishment of rights and citizenship». In this framework, mutual support must also be considered as inherent to the concept of solidarity, and its «institutionalisation» through citizenship implies that support mechanisms could (or even should) be set up by the State itself.

Furthermore, the bond created by the common interests or aims must be felt as essential by the members of the group, who are thus determined to preserve it. As Forst points out, «solidarity as a practical attitude exists as long as this bond is perceived to be important and binding and it materialises when corresponding action is felt to be required».

In a penetrating analysis in the field of philosophy, Sangiovanni defined solidarity as «a particular form of joint action characterised by a typical profile of commitments, intentions, and attitudes, and triggered by, inter alia, an identification with others on the basis of a shared cause, role, way of life, condition, or set of experiences». This definition includes the parameters already mentioned, namely the feeling of belonging to a community and the corresponding bond that urges the members of a group to commit themselves to the preservation of the common interests and goals. In this context, solidarity implies an action when needed, but also the commitment to act, the attitude of «being there», of «standing by».

It results from the above that solidarity can manifest itself in different ways, such as sharing resources and/or burdens in order to achieve an objective and promote a common goal, supporting each other in times of need, taking collective action to address a problem or to overcome an adversity. Furthermore, solidarity is usually conceived as based on the sameness of the members of the group, who are considered to be equal. However, this is not always the case: a group may consist of members who are equal and share common interests or objectives, but have different characteristics. In such cases, as Ross points out, solidarity «can re-evaluate the importance of differences and (re)discover similarities». The European Union, whose motto is «United in diversity», is perhaps the best example of this observation.

Another issue that is widely discussed in the literature is the relationship between solidarity and reciprocity. Sangiovanni affirms that «reciprocity lies at the heart of solidarity», in the sense that the relationships between the members of a given group are symmetrical and, therefore, they must all be committed to taking action to overcome adversity. Först takes a similar but more nuanced view; he argues that solidarity involves «a certain degree of reciprocity», which does not entail a strict do ut des situation but takes asymmetrical forms in the sense that a member of the group may undertake action, even if the other members are not in a position to reciprocate; this point is related to the differences that exist within the group. Hilpold notes

that solidarity, unlike altruism, is not unselfish and Garben presents the concepts of solidarity and reciprocity as communicating vases, emphasising that «the smaller the role of reciprocity, the higher the level of solidarity». It follows from the above that the notions of solidarity and reciprocity are not mutually exclusive, the latter being the element that distinguishes solidarity from charity or altruism. Reciprocity, however, should not be understood as a total equivalence between the respective actions, but rather as an expression of a mutual commitment stemming from a sense of belonging to the same group: the members of the group provide support to their peers when they are in need and they expect to receive support in return should they find themselves in a similar situation in the future. As Hilpold puts it, «solidarity expects solidarity».

It is not clear whether solidarity is limited to a state of mind that arises ipso facto from the existence of a special bond within a particular group, or whether it is a source of concrete obligations that must be assumed and respected by the members of the group. Först’s, Sangiovanni’s and Stjerno’s qualifications of solidarity as «the willingness to act», «joint action» and «readiness for collective action», respectively, do not refer to an obligation to show solidarity. However, if one attempts to go beyond the moral aspect of solidarity and to focus on its legal dimension, this question becomes crucial, as it requires reflection on its nature and role in a given legal order. Indeed, when solidarity is considered through a legal lens, the question of its legal effects and enforceability inevitably arises. In other words, it is important to identify the types of relationships that are established between the group members on the basis of solidarity, and the types of obligations, if any, that arise therefrom.

It is therefore necessary to move from the field of sociology, political theory or philosophy to the field of law; it should also be noted that, even within a given legal order, the meaning and role of solidarity varies across different areas of law.

There is no consensus in the legal scholarship on the role of solidarity in international law. Some authors link it to the concept of fraternity, which was one of the core values of the French Revolution and was later included in the 1948 Universal Declaration of Human Rights, which states that all human beings «should act towards one another in a spirit of brotherhood». This language reflects moral values rather than legal obligations for the subjects of international law. In 1996, Macdonald qualified solidarity as a principle of international law, which provides a context for meaningful cooperation among States and «reinforces the broader idea of a world community of interdependent States». Former ICJ judge Koroma has noted that solidarity guides States towards common good actions and, more recently, ICJ judge Tladi stressed that solidarity is «a sexy catchphrase» which, however, merely reflects an obligation to cooperate bilaterally or multilaterally under general international law. Eggett, on the other hand, identifies solidarity as a value of international law and calls for its further elaboration in the form of obligations of assistance and cooperation in specific areas.

The discussion on the value and place of solidarity in international law, with a particular focus on the individual, is also reflected in the effort to recognise it as part of «third-generation» human rights, which was expressed in a Resolution

of the UN Commission on Human Rights and the attempt to adopt a Declaration «on human rights and international solidarity», within the framework of the United Nations General Assembly. A Draft Declaration was submitted to the Human Rights Council in 2017, but it was received with scepticism, mainly reading the nature of solidarity as a human right. A revised Draft Declaration was elaborated in 2023, which defines international solidarity as «an expression of unity by which peoples and individuals enjoy the benefits of a peaceful, just and equitable international order, secure their human rights and ensure sustainable development» (article 1.1) and distinguishes between «preventive solidarity, reactive solidarity and international cooperation to solve global challenges» (article 2). It remains to be seen whether this document will be endorsed by the Human Rights Council.

It follows from the above that the field of international law, by its nature and function, is not best suited to the development of solidarity as a principle imposing binding obligations on States, either towards each other or towards individuals. It can be argued that the level of «common interests or aims», which is an inherent feature of solidarity, is too low and thus the bond among the members of the «group» better known as the international community, is too loose to generate a common willingness or readiness for collective action, i.e. an attitude of «standing by».

The situation is considerably different within the European Union legal order. Since its creation, the Union has introduced a new -or at least a renewed- concept of solidarity. In his famous Declaration of 9 May 1950, Robert Schuman stressed that «Europe will not be made all at once, or according to a single plan. It will be built through concrete achievements which will first create a de facto solidarity».

This phrase encapsulates an approach that differs from the classical sociological or philosophical understanding of the concept of solidarity, as mentioned

above. In the latter case, solidarity is derived, almost mechanically, from a pre-existing bond between the members of a group; this bond is based on their identification according to pre-existing common features, such as a role, a way of life, a set of shared experiences or a common cause. By contrast, the EU was founded by States which had fought each other in two successive world wars. In this case, solidarity was a deliberate choice and an objective to be achieved in order to guarantee peace on the European continent and thus, the creation of a community of European states (first the ECSC, then the EEC and Euratom) was seen as a means to achieve this objective. In other words, it was the vision of solidarity that led to the creation of a bond of common interests and objectives, and not vice versa. It should also be noted that, according to the Declaration, the realisation of concrete steps would gradually lead to a de facto solidarity, i.e. a solidarity based on the achievements of the Union. Solidarity can thus be qualified as the initial raison d’être and at the same time the ultimate «deliverable» of the European project.

The reference to solidarity in the Schuman Declaration was not just rhetoric: it was reaffirmed in the Preamble to the European Coal and Steel Community Treaty of 1951, which provided that «Europe can be built only through practical achievements, which will first of all create real solidarity, and through the establishment of common bases for economic development». In this phrase, solidarity is mentioned as a distinct parameter and placed on an equal footing with economic achievements, suggesting that it was perceived as a global objective that went beyond the strict limits of the market and encompassed all aspects of the European construction. Also, article 1 of the 1992 Treaty establishing the European Union (known as the Maastricht Treaty) provided that the said treaty «mark[ed] a new stage in the process of creating an ever closer union among the peoples of Europe and that the task of the Union, which is founded on the European Communities, supplemented by the policies and forms of cooperation established by that treaty, shall be to organise, in a manner demonstrating consistency and solidarity, relations between the Member States and between their peoples».

Today, EU primary law, as it stands after the Lisbon Treaty, contains numerous references to solidarity, which are worth mentioning here because they reflect the presence of this concept in all areas of the Union’s action. More specifically:

The Preamble of the Treaty on the European Union (hereafter: TEU) proclaims that the Member States desire «to deepen the solidarity between their

peoples while respecting their history, their culture and their traditions». This wording confirms that «sameness» among the members of a group is not always a prerequisite for the pursuit of solidarity or for the establishment of a system where solidarity prevails. Moreover, the reference to the «deepening» of solidarity implies that it is considered as an acquis of the Union, which must be further developed.

Article 2 TEU also proclaims the values on which the Union is founded, i.e. respect for human dignity, freedom, democracy, equality, the rule of law and respect for human rights, including the rights of persons belonging to minorities. It then recognises that these values are common to the Member States «in a society in which pluralism, non-discrimination, tolerance, justice, solidarity and equality between women and men prevail». Article 3(3) TEU provides that the Union shall promote, inter alia, solidarity between generations, as well as economic, social and territorial cohesion and solidarity among Member States. In addition, several provisions relating to the Union’s external action refer to solidarity: article 3(5) TEU provides that, in its relations with the wider world, the Union «shall contribute to peace, security, the sustainable development of the Earth, solidarity and mutual respect among peoples…». Respect for the principles of equality and solidarity is also mentioned among the principles that guide the Union’s action on the international scene (art. 21(1) TEU), and the Common Foreign and Security Policy (CFSP) is «based on the development of mutual political solidarity among Member States», which shall support that policy «in a spirit of loyalty and mutual solidarity» (article 23(2) and (3), articles 31(2), and 32 TEU).

The Preamble of the Treaty on the Functioning of the European Union (hereafter: TFEU) refers to the intention of Member States «to confirm the solidarity which binds Europe and the overseas countries». Also, article 67(2) TFEU provides that the functioning of the Area of Freedom, Security and Justice is «based on solidarity between Member States» and article 80 TFEU affirms that the policies of the Union in this field and their implementation «shall be governed by the principle of solidarity and fair sharing of responsibility between Member States». Furthermore, solidarity is mentioned in articles 122 TFEU concerning the adoption of measures dealing with emergencies and economic crises, 194 TFEU on energy policy, as well as in article 222 TFEU entitled «Solidarity clause», which provides for the taking of joint action in case a Member State is the object of a terrorist attack or a victim of a disaster.

Finally, the Preamble of the Charter of Fundamental Rights of the European Union recognises solidarity as a «universal value» along with human dignity, freedom and equality. The Title IV of the Charter is entitled «Solidarity» and it includes several social rights, such as the right to fair working conditions, social security and assistance, health care, etc.

It is clear from the above that the notion of solidarity is ubiquitous in the EU legal order and it is used in different contexts and fields of action. Such dispersion inevitably leads to uncertainty as to its legal nature, role and legal effects. In this respect, it is interesting to note that scholars have proposed different typologies of solidarity based on various criteria, such as the nature of the concept, its role or the actors involved with its realisation. Blanquet has qualified the Union as a «crossroads of solidarities» and has identified three dimensions of solidarity in the Treaties based on the actors involved, i.e. solidarity between the peoples of Member States, between Member States, and between the Union and the Member States. In a similar approach, Sangiovanni considers that the concept of solidarity in the EU is threefold and consists of national solidarity, which concerns the relations between citizens and residents at the level of the Member States, Member State solidarity, which governs the relations between the Member States, and transnational solidarity, which applies between EU citizens qua citizens. Similarly, Domurath identifies three dimensions of solidarity in the EU Treaties: solidarity between Member States, between Member States and individuals, and between generations. Furthermore, Van Cleynenbreugel refers to four conceptions thereof, i.e. liberalising, redistributive, constitutive and administrative, noting that the first two conceptions promote substantive economic and social solidarity among Member States and the other two bring forward transnational solidarity governing their interactions.

Ruccia’s attempt at a typology focuses on the different functions of solidarity in the EU legal order and identifies four types of it: preventive solidarity, which is meant to prevent breaches of EU law and shape Member States’ actions mainly in the field of the CFSP; corrective solidarity, which provides assistance to Member States in case of hardship; redistributive solidarity, which aims to ensure cohesion and eliminate inequalities between Member States; and emergency solidarity, which is activated in times of crisis.

Last but not least, Schiek has proposed an interesting taxonomy of solidarity using as a database the EU Court’s case law mentioning this concept (122 cases until September 2019). Based on an analysis of the Court’s approach, she distinguished between several dimensions and types of solidarity: the dimensions concern solidarity (a) between Member States and citizens of other Member States, (b) between citizens, (c) between the Union and its Members (towards each other) and (d) external solidarity. Furthermore, she identified three categorial types of solidarity, i.e. solidarity as charity, as mutual obligation and as risk mitigation, which in turn imply three functional types of solidarity depending on its purpose, i.e. solidarity as charity on a voluntary basis, as a legally enforceable mutual obligation, as a tool to embed individual rights as, lastly, as a tool to embed economic integration.

The attempt to distinguish between the different types of solidarity is coupled with a discussion concerning its nature, which is also linked to its role and legal effects in the EU legal order. Several views have been expressed in this regard. It has been argued that solidarity constitutes a value with no legally binding force, an «emerging constitutional value shaping or directing other core values of legal institutions», an objective, a general principle, a fundamental

principle, an institutional principle or even a legal obligation,. It has also been argued that the nature of solidarity is threefold, i.e. a value, a principle and a rule. In this regard, scholars explore and build on the references to solidarity as contained in EU law provisions as well as in the case law, both in the Court’s judgments and in the Opinions of Advocates General.

It follows from all of the above that the concept of solidarity, while undeniably central to the EU legal order, is complex and challenging as regards the definition of its context and its nature.

Almost 30 years ago, in my doctoral thesis concerning the origin, the status and the materialisation of the general principles of law in the case law of the European Court of Justice, I included solidarity among the «structural» principles of the -then- European Community legal order, and argued in favour of its nature as an inherent element thereof.

The purpose of this study is to revisit solidarity and attempt to further explore its role and its dynamics taking into account the evolution of the Union’s legal order and the institutional framework introduced by the Lisbon Treaty. Indeed, as mentioned above, primary EU law now contains several explicit references to solidarity in different legal contexts and areas of EU competence.

In this respect, the study will build on the writings of scholars who have approached the concept of solidarity through different epistemological lenses. I will also examine the case law of the Court of Justice of the European Union,

which has always been a source of inspiration and a constant driving force of European integration.

The present study follows a binary logic that seeks to identify the context and circumstances in which the concept of solidarity is intended to produce its effects. The first part analyses solidarity as a concept that permanently governs (or should govern) the relations between the subjects of the Union’s legal order, i.e. EU institutions, Member States and individuals. The second part examines the role and effects of solidarity as a mechanism activated to respond to emergency situations. On the basis of this approach, the study seeks to identify the nature of the concept of solidarity in each type of situation and, finally, to draw conclusions on its overall role and place in the EU legal order.

PART I

«STANDING BY»: SOLIDARITY AS A STRUCTURAL
CONCEPT OF THE EU LEGAL ORDER

This Part examines solidarity as a concept inherent to the European Union, in the sense of the vision described in the Schuman Declaration, i.e. as a permanent element that should underpin the integration project as a whole. It aims to identify the nature and intensity of the commitments that it entails for the Member States and the EU institutions, . Within this framework, Chapter A focuses on solidarity as an existential concept for the functioning of the Union, which shapes and dictates the general framework of the relationships that must bind the EU actors together. Chapter B examines solidarity as a source of specific obligations for EU actors, and explores the nature of such obligations, both horizontally and in different policy areas of the Union.

Chapter A

SOLIDARITY AS AN EXISTENTIAL CONCEPT SHAPING THE
RELATIONS BETWEEN EU ACTORS

As mentioned above, solidarity was both the starting point and the ultimate goal of the European Union. In this context, it is referred to as a «constitutional» concept; this means that it sets the framework, within which Member States and EU institutions must interact as well as the way in which they must treat EU citizens. As Lenaerts and Adam note, «legal and institutional solidarity or systemic solidarity has been the cement of European integration from the outset».

The constitutional nature of the concept of solidarity means that it is an integral part of the European project and must be safeguarded, irrespective of any explicit reference to it in the Treaty provisions. Thus, the Court of Justice has already recognised solidarity in its early case law as an unwritten principle which underpins the EU legal order as a whole; both the judgments of the Court and the opinions of its Advocates General have consistently emphasised the importance of solidarity in various areas of EU law (Paragraph 1). Moreover, since the essence of solidarity is to shape the behaviour of EU actors, both scholars and case law have explored its relationship, direct or indirect, with other similar concepts, such as the duty of sincere cooperation, also known as the principle of loyalty, or the principle of mutual trust (Paragraph 2).

Paragraph 1. Solidarity as an unwritten concept and its
recognition in the case law of the Court of Justice

The Court of Justice is the institution that is entrusted with the mission to «ensure that in the interpretation and application of the Treaties the law is observed» (article 19(1) TEU). The Union judge has perceived its role in a dynamic way, mainly adopting a teleological approach in order to safeguard and serve the objective of integration. As Craig and De Burca point out, its case law «[gave] substance to an “outline” Treaty, thereby enhancing the effectiveness of EU law and promoting its integration into national legal systems». In this context, it has developed a number of principles which, although not provided for in the Treaties are nonetheless inherent in the Union’s legal order, such as primacy, direct effect, or non-contractual liability of the Member States for infringements of EU law. It has also recognised the role of general principles such as proportionality, legal certainty, good administration, etc.

Solidarity has largely been mentioned in the case law as an unwritten concept of EU law. In this Paragraph I will analyse the case law which proclaimed the concept of solidarity before (a) and after (b) its inclusion in the Treaty of Lisbon.

a. The jurisprudential recognition of solidarity before the Lisbon Treaty

So far, the absence of express written provisions has hardly prevented the Court from recognising a concept as being part of the EU legal order. It thus stressed the importance of solidarity even under the original institutional

framework where this concept was mentioned only in the Preamble of the ECSC and EEC Treaties -the latter referring to solidarity only in relation to overseas countries. The case law issued prior to the Lisbon Treaty clearly demonstrates the central role of solidarity in the European project.

The first direct reference to solidarity came in 1969, in an infringement procedure against France which maintained an advantage in favour of French exporters in the form of a preferential discount rate for credits given for exports. In its judgment the Court referred to «solidarity, which is at the basis […] of the whole of the Community system». Although the Court linked solidarity to the duty of loyalty of article 5 CEE (now 4(3) TEU) as well as with the mutual assistance obligation of article 108 EEC (now 122 TFEU), the fact that it recognised it as underpinning the whole system means that the Treaty provisions can be seen as a specific expression of the pre-existing concept of solidarity.

Similarly, in the field of the common agricultural policy, the Court held that Italy’s failure to adopt measures for the application of a Regulation providing for a premium for the slaughter of cows constituted «a failure in the duty of solidarity accepted by Member States by the fact of their adherence to the Community [which] strikes at the fundamental basis of the Community legal order». Given that, as provided for in the Treaty (article 189 EEC, now 288 TFEU), regulations are binding in all their features and create obligations for Member States, the Court could have limited its judgment to stating that Italy had failed to fulfil its obligations under the specific Regulation and article 189 EEC. Instead, it took the opportunity to stress that the participation in the Community ipso facto creates a bond, which cannot be dissociated from the concept of solidarity. What is more, this judgment clearly showed that the obligation of the Member States to implement and respect EU law must be considered as an expression of solidarity.

The Court reiterated this position in the Benzine Petroleum case, which concerned an action for the annulment of a Commission decision accusing oil companies of abusing of their dominant position during the 1973 oil crisis.

This judgment is very interesting in that it emphasised that the absence of appropriate rules at the Community level, which would allow the adoption of suitable conjunctural measures, revealed «a neglect of the principle of Community solidarity [which] is one of the foundations of the Community». Once again, solidarity seems to serve as a substructure on which all the specific principles and commitments of EU actors are based. At the same time, solidarity is implicitly recognised as an obligation also for the Union; failure to adopt rules in this case would jeopardise solidarity.

Similarly, in an action for failure to fulfil obligations brought by the Commission against the United Kingdom for refusing to take measures to implement a regulation requiring the introduction of recording equipment in road transport, the Court stated that «for a State unilaterally to break, according to its own conception of national interest, the equilibrium between the advantages and obligations flowing from its adherence to the Community brings into question the equality of Member States and creates discrimination at the expense of their nationals. This failure of the duty of solidarity accepted by Member States by the fact of their adherence to the Community strikes at the very root of the Community legal order». The Court of First Instance (now the General Court) also emphasised, in an action for annulment of a Commission decision in the field of State aid, that derogations from the principle of free competition in favour of regional aid are based «on the aim of Community solidarity, a fundamental objective of the Treaty, as may be seen from the Preamble». As pointed out by Blanquet, the reference to the Preamble in this case must be considered as concerning solidarity only indirectly through the stated objective of reducing the gap between regions of the EU (since solidarity was mentioned in the Preamble of the EEC Treaty only in relation to the overseas countries).

Therefore, solidarity is perceived by the Court as the central idea that binds the Member States to the Union and requires them to comply with the obligations laid down in EU primary and secondary law. Participation in the Union implies the acceptance of solidarity as an essential feature thereof. If a Member State fails to comply with an obligation laid down in the Treaties or in a regulation or directive, it is not only in breach of those specific rules but also of its solidarity obligations. The latter are associated to the balance

between benefits and obligations entailed by the participation in the EU; in this respect, solidarity also implies a strong aspect of reciprocity, in the sense that EU actors enter into mutually binding commitments. On several occasions the Court has pointed out that solidarity is at the heart of Community aid schemes to producers or of common market organisations under the Common Agricultural Policy, which establish a balance between the rights and obligations of economic operators. In this context, it is interesting to note that the Court of Justice ruled on an action for annulment brought by Spain against a Regulation, which provided for a reduction in guaranteed quantities in the milk sector in order to deal with surpluses. Spain pleaded, inter alia, breach of the principle of non-discrimination, arguing that the specific situation of the Spanish milk production had not been duly taken into account and that, after all, Spain had not contributed to the creation of Community surpluses in the milk sector. The Council held that this argument was contrary to the principle of solidarity and the Court ruled that «the reduction of total guaranteed quantities is a measure intended to deal with the imbalance between the supply of and demand for milk products and requires […] a concerted effort by all the Community producers in equal measure». Although this judgment does not refer directly to solidarity, it highlights its importance in a community where benefits and burdens are shared in a balanced way. In other words, this case law has used solidarity as

part of a balancing exercise that must be carried out among various objectives and interests, in order to assess the legality and validity of EU acts.

While it is true that solidarity is by its nature well suited to the field of agricultural policy, it has also been mentioned by the Court in other areas. For example, solidarity was identified as one of the main driving forces behind the Framework Decision on the European Arrest Warrant: when the Court was called to judge upon an action for annulment brought against that act, it stressed that the European Arrest Warrant is «based on the principle of mutual recognition and [operates] in the light of the high degree of trust and solidarity between the Member States». This aspect of solidarity focuses on both bilateral and multilateral relations among the Member States and implies a high degree of mutual trust, .

Furthermore, in the case of Member States which have exempted the import of military equipment from customs duties on the grounds of their essential security interests under article 296 EC (now article 346 TFEU), the Court of Justice ruled that «a Member State cannot be allowed to plead the increased cost of military material because of the application of customs duties on imports of such material from third countries in order to avoid, at the expense of other Member States who collect and pay the customs duties on such imports, the obligations which the principle of joint financing of the Community budget imposes on it».