Opinion of Mr Advocate General Mengozzi delivered on 16 December 2010.

A — Directive 2009/12/EC

3. The directive in issue was adopted on the basis of Article 80(2) EC. Its purpose is to establish ‘common principles for the levying of airport charges at Community airports’ (Article 1(1)).

4. Recitals 2, 3 and 4 of the preamble to the Directive are worded as follows:

‘(2) It is necessary to establish a common framework regulating the essential features of airport charges and the way they are set, as in the absence of such a framework, basic requirements in the relationship between airport managing bodies and airport users may not be met....

(3) This Directive should apply to airports located in the Community that are above a minimum size as the management and the funding of small airports do not call for the application of a Community framework.

(4) In addition, in a Member State where no airport reaches the minimum size for the application of this Directive, the airport with the highest passenger movements enjoys such a privileged position as a point of entry to that Member State that it is necessary to apply this Directive to that airport in order to guarantee respect for certain basic principles in the relationship between the airport managing body and the airport users, in particular with regard to transparency of charges and non-discrimination among airport users.’

5. According to recital 19, the objective of the Directive ‘cannot be sufficiently achieved by the Member States as systems of airport charges cannot be put in place at national level in a uniform way throughout the Community and can therefore, by reason of its scale and effects, be better achieved at Community level’.

6. In accordance with Article 1(2), the Directive applies ‘to any airport located in a territory subject to the Treaty and open to commercial traffic whose annual traffic is over five million passenger movements and to the airport with the highest passenger movement in each Member State’.

7. Essentially, the Directive requires Member States to establish a procedure for regular consultation, at least once a year, between the airport managing body and airport users, on the operation of the system of charges for the use of infrastructure and services provided by the former to the latter (Article 6(1)). In that context, both parties are placed under a mutual duty to provide the information needed in order to set airport charges (Article 7).

8. Every Member State must establish an independent supervisory authority to ensure that the obligations laid down in the Directive are fulfilled (Article 11), whose intervention the parties may seek in the event of a disagreement over a decision on airport charges (Article 6(3)).

9. The Commission is to draw up, by 15 March 2013, a report assessing the application of the Directive, progress made in attaining its objectives, and the need for appropriate amendments (Article 12).

10. The deadline for transposition of the Directive into national law was set at 15 March 2011 (Article 13).

A — Breach of the principle of non-discrimination

16. Luxembourg argues breach of the principle of non-discrimination inasmuch as the Directive engenders both different treatment of similar situations and similar treatment of different situations.

17. As far as concerns the first aspect of this discrimination, Luxembourg complains that the inclusion within the Directive’s scope of airports such as that at Luxembourg-Findel (‘Findel Airport’) entails administrative burdens and costs for such airports that other airports in a comparable situation, that is to say, large regional airports with fewer than 5 million passenger movements a year, escape, without that difference in treatment being objectively justified.

18. Particular reference is made to the airports of Charleroi, in Belgium, and Hahn, in Germany, which, located within the same catchment area as Findel, are in direct competition with it. Findel Airport (which saw 1 642 848 passenger movements in 2007) falls within the Directive’s scope of application for the reason that it is Luxembourg’s main airport. By contrast, the two airports just mentioned, whilst serving more passengers (in 2008 they recorded 2.9 million and 4 million passenger movements respectively) do not fall within the scope of the Directive because they do not serve more than 5 million passengers a year and are not the main airports of their respective Member States.

19. As far as concerns the second aspect of this discrimination, however, Luxembourg complains that it is being treated in similar fashion to other Member States, such as Belgium and Germany, which nevertheless have airports that serve considerably more than 5 million passengers a year. The situation in which the main airports of those Member States find themselves is different and they should not, therefore, be subject to the same burdens.

20. It is Luxembourg’s opinion that the ‘privileged position’ enjoyed by the main airports does not confer on airports that have relatively few passengers, such as Findel Airport, an advantage of the same type as that gained by having a high passenger throughput. What is more, even from an economic point of view, Findel Airport is hardly comparable with the large international airports.

21. Luxembourg takes issue with the statement contained in recital 4 of the preamble to the Directive and disputes that the main airport of each Member State enjoys a privileged position as a ‘point of entry’ into that Member State. By inserting this fourth recital, the Council sought to provide an ex post facto justification for the inclusion within the Directive’s scope of at least one airport per Member State.

22. According to Luxembourg, the risk of a dominant position’s being taken is much greater in the case of regional airports that are significantly larger than Findel Airport and, whilst being located close to large urban centres, are not the main airports of their respective Member States and are thus excluded from the scope of the Directive. Findel is being discriminated against by comparison with such airports because of a difference in treatment based on the mere difference in the nationality of the airport.

23. Lastly, Luxembourg finds no justification for the legislature having imposed burdens on Findel Airport that, in its view, are discriminatory. Any complex assessments that had to be carried out during the drafting of the Directive could not, in its opinion, have related to such an obviously simple situation as that of Findel Airport.

24. Slovakia joins Luxembourg in the objections which it puts forward in connection with costs and administrative burdens, adding, in particular, that the administrative and supervisory procedures laid down by the Directive (such as the right of airport users to have recourse to an independent authority in the event of a dispute over a decision taken by the airport managing body) might impede the decision-making process and thus make airports less competitive.

25. For its part, the Council submits that, in creating a context of transparency for airport charges for the benefit of the aviation sector, the legislature could not ignore the privileged position of the main airports of the various Member States, whose position makes them comparable to airports registering more than 5 million passenger movements a year. In this connection, the Council denies that extending the scope of the Directive to airports serving the greatest number of passengers in each Member State was an ex post facto addition. In any event, even if the scope of the Directive as originally proposed (which covered airports serving more than a million passengers a year or handling more than 25 000 tonnes of cargo a year) had not been altered, Findel Airport, which in 2008 recorded annual cargo of over 700 000 tonnes, would still have been subject to the provisions of the Directive.

26. The Council also submits that Luxembourg has failed to prove the difference in treatment of which it complains. There is no evidence to prove as a fact that the airports of Charleroi and Hahn enjoy a privileged position similar to that enjoyed by the main airports of the Member States, nor to prove as a fact that the airlines normally active at Findel Airport would be induced to abandon it and move to Charleroi or Hahn.

27. According to the Parliament, only by making the Directive applicable to all Member States was it possible to improve transparency and reduce discrimination in the fixing of airport charges by the managing bodies. Moreover, in this way, the airlines were left with a choice, in every Member State, of at least one airport that is subject to the Community rules on airport charges.

28. Secondly, the Parliament maintains that the obligations arising under the Directive do not entail such costs as would put Findel Airport at a disadvantage by comparison with airports not subject to its rules.

29. The Parliament further insists, with the Council in agreement, on the necessity of the Directive’s being applied in every Member State. Seen from that perspective, the provision with which Luxembourg takes issue is an essential element of the general structure of the Directive, since it ensures that, in every Member State, there is at least one airport that is required to comply with the rules of transparency in the field of airport charges.

30. The Commission, for its part, supports the interpretation which the Parliament and the Council give to the Directive. In particular, in connection with the justification contained in recital 4, it states that only two categories of airport might find themselves in a position of strength vis-à-vis the airlines: the main airports of each Member State, since they are the principal ‘point of entry’ into that country, and airports exceeding the threshold of 5 million passenger movements a year.

31. As far as the Commission is concerned, the criterion of ‘main’ airport in each Member State is, in light of the Directive’s purpose, the mainstay of the system of rules governing airport charges. The criterion of more than 5 million passenger movements a year, on the other hand, serves merely to complement the first criterion.

B — Breach of the principles of proportionality and subsidiarity

32. In so far as concerns the principle of proportionality, Luxembourg submits that the procedures and administrative burdens flowing from the Directive are excessive and out of proportion with the reality of Findel Airport’s situation.

33. As regards the principle of subsidiarity, the plaintiff Member State argues that it is unnecessary, in the management and financing of airports serving fewer than 5 million passengers a year, to apply a Community framework. Proof of that assertion lies in the fact that many airports larger than Findel Airport are exempt from the obligations arising under the Directive.

34. The Council disputes that argument, on the presumption that the regulation of airport charges calls for complex assessments which leave the legislature with a broad discretion that will be open to criticism only in the event of obvious error. In accordance with that presumption, it submits that the action should be dismissed since it has not been demonstrated that the measure in question is manifestly inappropriate to the objectives pursued by the Community legislature.

35. The Council also submits that the fundamental principles underlying the Directive, that is to say, transparency, non-discrimination and consultation, make it easier not only for airlines but also for airports to conduct their business. In its opinion, given that the definition of such common principles may be better carried out by the European Union, Luxembourg has failed to demonstrate in what way the principle of subsidiarity has been breached.

36. The Parliament adopts largely the same position as the Council, adding that the proportional nature of the Directive is self-evident given the very low level of obligations laid down in it.

37. The Commission, for its part, points out that the principles of compulsory consultation and non-discrimination have already been adopted in the majority of the Member States, a situation which, in terms of administrative burdens, attenuates the effect of the Directive on the airport systems in those Member States.

A — Preliminary observations

B — The limits of the review of the validity of the Directive

55. The directive in issue in the present action was adopted on the basis of Article 80(2) EC. It is settled case-law that, in the transport sector, as in all sectors in which assessments of a political, economic and social nature must be made, the legislature enjoys a broad margin of discretion.⁽¹⁰⁾ In such situations the Court speaks of ‘complex assessments’.⁽¹¹⁾ Complex, that is, because of the difficulties which arise on attempting to reconcile divergent interests or because of the political responsibilities involved in economic and social regulation. When reviewing the lawfulness of legislative acts relating to such sectors, the Court is not asked to give its opinion on the appropriateness of the choices made by the legislature, but to penalise legislative choices that are vitiated by a manifest error of assessment.⁽¹²⁾

56. Furthermore, the discretion allowed by the Community legislature includes the possibility of establishing, in overall terms, which facts it must take into account when making its choices. Indeed, as the Court has already had occasion to clarify, when the implementation of a common policy, such as that for transport, requires the assessment of a complex situation, the institutions’ discretion is exercisable not only in relation to the nature and scope of the provisions to be adopted but also, to a certain extent, to checking the essential facts, which it may do on the basis of findings of a general nature.⁽¹³⁾

C — Breach of the principle of non-discrimination

57. According to settled case-law, the principle of non-discrimination requires similar situations not to be treated differently and different situations not to be treated in the same way, unless that is objectively justified.⁽¹⁴⁾

58. I shall now deal separately with the distinct aspects of the discrimination of which Luxembourg complains in order to determine, first and foremost, whether the situations which that Member State uses in its comparison are indeed similar to its own and, if they are, whether the treatment of which it complains is actually discriminatory.

59. In the light of the considerations just mentioned in connection with the legislature’s discretion, the question that must be asked, for the purposes of the comparison, is whether the decision to treat the ‘main’ airports of each Member State in the same way as airports with more than 5 million passenger movements, and differently from ‘secondary’ airports that have a similar volume of passenger traffic to ‘main’ airports, amounts to a difference in treatment arising from a manifest error of assessment. That point must be assessed in the light of the object pursued by the legislature, which, as we have seen, is to prevent abusive conduct on the part of airport managing bodies with regard to airlines.

D — Breach of the principle of proportionality

97. An assessment of proportionality is logically connected with an assessment relating to non-discrimination.⁽²³⁾ It is clear from the considerations developed above in relation to the principle of non-discrimination that the dual criteria chosen by the legislature in order to establish the scope of Directive may be explained by reference to the objective of ensuring that airports do not abuse their dominant position to the detriment of the airlines. I shall now proceed to assess this connection between the provision in issue and the objective pursued from the point of view of proportionality.

98. According to settled case-law, the principle of proportionality requires the choices made by the legislature to be suited to achieving the desired objective and must not go beyond what is necessary to achieve it.⁽²⁴⁾ Given the discretion allowed the Community legislature in regulating airport charges, it is not a question of establishing whether the measure adopted by the legislature was the only one or the best one possible,⁽²⁵⁾ but of ensuring that the choice made by the legislature was not manifestly unnecessary or inappropriate having regard to the objective pursued by the Directive.⁽²⁶⁾

99. In the present case, main airports were included within the scope of the Directive on the assumption that there was a risk of abusive conduct because of the strategic advantages which that category of airport generally enjoys. The applicant has failed to prove that that assumption was manifestly incorrect.⁽²⁷⁾ Against that background, and on the basis of an overall assessment of the state of the airport sector, the legislature thus decided that it was necessary to establish a supervisory authority in every Member State, in order to promote more transparent regulation of airport charges, with reference to the situation of the air transport sector in the Union. It does not seem to me that, in and of itself, making provision for such a body may be considered arbitrary or manifestly unnecessary, especially if account is taken of possible changes in the regulation of airport charges arising from the results obtained.⁽²⁸⁾

100. More particularly, as regards, the specific impact of the obligations imposed by the Directive on the actual situation obtaining within airports, it is necessary to establish whether, by the introduction of the ‘main airport’ criterion, the legislature did not impose on that category of airport greater burdens than were necessary in order to counter the risk of abusive conduct.

101. Luxembourg and Slovakia complain that applying the Directive to their own main airports would entail burdens which, proportionally speaking, would have a greater adverse effect on them than on airports recording more than 5 million passenger movements a year.

102. However, it must be noted that, in assessing whether or not the measure is manifestly inappropriate, the simple fact that the solution adopted by the legislature puts one group at a greater disadvantage than another is irrelevant.⁽²⁹⁾ The importance of the objectives pursued might even justify substantial negative economic consequences for certain operators,⁽³⁰⁾ and the Court may intervene only when such legislative choices appear to be manifestly incorrect or when the resultant disadvantages for certain economic operators are wholly disproportionate to the advantages otherwise offered.⁽³¹⁾ To be more specific then, fault could be found with the ‘main airport’ criterion only if it were proved that the administrative burdens generally imposed on airports recording fewer than 5 million passenger movements outweighed the benefits flowing from application of the Directive and increased their operating costs to the point of permanently compromising their competitiveness.⁽³²⁾

103. I do not think that Luxembourg has furnished such proof. As I observed earlier,⁽³³⁾ the costs which, according to Luxembourg, would ensue from the establishment of the supervisory body would not result in any increase in airport charges such as to cause airlines to decide to abandon it in favour of other competing airports. Moreover, I do not believe that the minimum level of harmonisation required by the Directive can have any significant effect on the situation of airports which, in many cases, have already begun to align themselves with the guarantees of transparency and non-discrimination suggested in the past by the Council of the International Civil Aviation Organization.⁽³⁴⁾ It does not, therefore, seem to me that the theoretical costs put forward by Luxembourg are disproportionate to the interest in implementing the Directive in all the Member States.

104. I therefore take the view that including the main airport of each Member State within the scope of the Directive does not go beyond what was necessary to counter the risk of abusive conduct on the part of airport managing bodies to the detriment of airlines. In conclusion, I do not consider that the Community legislature can be charged with any breach of the principle of proportionality.

E — Breach of the principle of subsidiarity

105. The principle of subsidiarity, as is well-known, requires that, in areas which do not fall within its exclusive competence, the Union is to take action only if and in so far as the objectives of the proposed action cannot be sufficiently achieved by the Member States and can therefore, by reason of the scale or effects of the proposed action, be better achieved at Union level.⁽³⁵⁾

106. In so far as concerns the directive in issue in the present case, I have already pointed out⁽³⁶⁾ that, on the basis of Article 80(2) EC, it establishes common principles for the levying of airport charges in the airports of the Community in order to prevent abusive conduct on the part of airport managing bodies with regard to airline companies. According to the Community legislature, that objective ‘cannot be sufficiently achieved by the Member States as systems of airport charges cannot be put in place at national level in a uniform way throughout the Community and can therefore, by reason of its scale and effects, be better achieved at Community level’.⁽³⁷⁾

107. Luxembourg disputes that a Community framework is necessary for airports having fewer than 5 million passenger movements, relying on the fact that the Directive excludes from its own scope many airports of that size.

108. Given the considerations I have expressed in relation to the dual criteria selected by the legislature in the exercise of the discretion allowed it in the sector, I find Luxembourg’s observation lacking in pertinence. Indeed, airports having fewer than 5 million passenger movements which do fall within the scope of the Directive, such as Findel Airport, are included because they are main airports, irrespective of the number of their passenger movements.

109. To leave it up to Member States to regulate airport charges in their own main airports having fewer passenger movements than the 5 million a year threshold would give rise to the divergent development of national rules. Such divergence could, in the long term, lead to inefficiency, and in the immediate present also make it easier for airports to adopt abusive conduct to the detriment of the airlines. Lastly, the fact should not be forgotten that air traffic is, by its very nature, a largely international matter and is therefore generally ill suited to being regulated at the level of the individual Member States.

110. It follows that the Directive’s objective could not be achieved sufficiently well by means of action taken at national level.

111. In conclusion, by defining the scope of the Directive by reference to the dual criteria set out in Article 1(2), the Community legislature did not, in my opinion, breach the principle of subsidiarity.