–

Right to Know CLG, by D. Browne, Barrister-at-Law, F. Logue, Solicitor, and N.J. Travers, Senior Counsel,

–

An Taoiseach and Ireland, by M. Browne, E. O’Hanrahan and A. Joyce, acting as Agents, and by A. Carroll, Barrister-at-Law, and B. Kennedy, Senior Counsel,

–

the European Commission, by G. Gattinara and L. Haasbeek, acting as Agents,

1

This request for a preliminary ruling concerns (i) the interpretation of point (e) of the first subparagraph of Article 4(1) and of point (a) of the first subparagraph of Article 4(2) of Directive 2003/4/EC of the European Parliament and of the Council of 28 January 2003 on public access to environmental information and repealing Council Directive 90/313/EEC (OJ 2003 L 41, p. 26), and (ii) the principles of res judicata and effectiveness.

2

The request has been made in proceedings between Right to Know CLG, a not-for-profit organisation governed by Irish law, and An Taoiseach (Prime Minister, Ireland) concerning a request addressed to the Government of Ireland on 8 March 2016 seeking access to all documents relating to cabinet discussions regarding Ireland’s greenhouse gas emissions which took place during meetings held from 2002 to 2016 (‘the request for access to environmental information of 8 March 2016)’.

3

The Convention on access to information, public participation in decision-making and access to justice in environmental matters, signed in Aarhus on 25 June 1998 and approved on behalf of the European Community by Council Decision 2005/370/EC of 17 February 2005 (OJ 2005 L 124, p. 1; ‘the Aarhus Convention’), provides, in Article 4(3) and (4) thereof:

‘3.   A request for environmental information may be refused if:

…

4.   A request for environmental information may be refused if the disclosure would adversely affect:

…’

4

Recital 16 of Directive 2003/4 is worded as follows:

‘The right to information means that the disclosure of information should be the general rule and that public authorities should be permitted to refuse a request for environmental information in specific and clearly defined cases. Grounds for refusal should be interpreted in a restrictive way, whereby the public interest served by disclosure should be weighed against the interest served by the refusal. The reasons for a refusal should be provided to the applicant within the time limit laid down in this Directive.’

5

According to Article 1 of that directive, entitled ‘Objectives’:

‘The objectives of this Directive are:

6

Article 2 of Directive 2003/4, entitled ‘Definitions’, provides:

‘For the purposes of this Directive:

…

…

…’

7

Article 4 of that directive, entitled ‘Exceptions’, provides:

‘1.   Member States may provide for a request for environmental information to be refused if:

…

…

2.   Member States may provide for a request for environmental information to be refused if disclosure of the information would adversely affect:

…

The grounds for refusal mentioned in paragraphs 1 and 2 shall be interpreted in a restrictive way, taking into account for the particular case the public interest served by disclosure. In every particular case, the public interest served by disclosure shall be weighed against the interest served by the refusal. Member States may not, by virtue of paragraph 2(a), (d), (f), (g) and (h), provide for a request to be refused where the request relates to information on emissions into the environment.

…

4.   Environmental information held by or for public authorities which has been requested by an applicant shall be made available in part where it is possible to separate out any information falling within the scope of paragraphs 1(d) and (e) or 2 from the rest of the information requested.

…’

8

Article 6 of Directive 2003/4, entitled ‘Access to justice’, requires Member States to ensure that any applicant seeking environmental information who considers that his or her request has been ignored, wrongfully refused, inadequately answered or otherwise not dealt with in accordance with the provisions of that directive can seek administrative or judicial review of the acts or omissions of the public authority concerned.

9

Article 28(4) of the Bunreacht na hÉireann (Constitution of Ireland) provides:

‘…

2° The Government shall meet and act as a collective authority …

3° The confidentiality of discussions at meetings of the Government shall be respected in all circumstances save only where the High Court determines that disclosure should be made in respect of a particular matter:

…’

10

Directive 2003/4 was transposed into Irish law by the European Communities (Access to Information on the Environment) Regulations 2007 (S.I. No 133/2007) (‘the Regulations on access to information on the environment’).

11

Article 8 of those regulations provides for certain mandatory grounds for refusal of a request for access to environmental information. The exception relating to ‘proceedings’ is transposed by Article 8(a)(iv) of those regulations.

12

Article 8(b) of the Regulations on access to information on the environment provides that a public authority is not to make available environmental information ‘to the extent that it would involve the disclosure of discussions at one or more meetings of the Government’.

13

Article 9 of the Regulations on access to information on the environment sets out the grounds on which a request for access to environmental information may be refused. The exception relating to ‘internal communications’ is transposed by Article 9(2)(d) of those regulations.

14

Article 10 of the Regulations on access to information on the environment provides:

‘(1)   Notwithstanding articles 8 and 9(1)(c), a request for environmental information shall not be refused where the request relates to information on emissions into the environment.

(2)   The reference in sub-article (1) to information on emissions into the environment does not include a reference to any discussions on the matter of such emissions at any meeting of the Government.

(3)   The public authority shall consider each request on an individual basis and weigh the public interest served by disclosure against the interest served by refusal.

(4)   The grounds for refusal of a request for environmental information shall be interpreted on a restrictive basis having regard to the public interest served by disclosure.

(5)   Nothing in article 8 or 9 shall authorise a public authority not to make available environmental information which, although held with information to which article 8 or 9 relates, may be separated from such information.

…’

15

The request for access to environmental information of 8 March 2016, submitted by Right to Know, sought, in essence, to obtain access to records of meetings of the Government of Ireland. On 27 June 2016, that request was refused, following an internal review procedure. Right to Know challenged that decision before the High Court (Ireland).

16

By a judgment of 1 June 2018, that court held that the exception to the right of access to environmental information laid down in point (e) of the first subparagraph of Article 4(1) of Directive 2003/4 in respect of ‘internal communications’ of a public authority was applicable since meetings of the Government of Ireland had to be characterised as such communications. It also found that the application of that exception required the public interest served by disclosure to be weighed against the interest served by refusal, and that the decision of 27 June 2016 did not do so. The High Court therefore quashed that decision and remitted Right to Know’s request to the Prime Minister for reconsideration.

17

By a decision of 16 August 2018, the Prime Minister granted Right to Know’s request, but only in part. Right to Know has challenged the legality of that decision before the High Court.

18

In the context of its action, Right to Know challenges the characterisation of the requested documents as adopted by the High Court in its judgment of 1 June 2018. According to Right to Know, it is necessary to disregard the exception laid down in point (e) of the first subparagraph of Article 4(1) of Directive 2003/4 in respect of ‘internal communications’ and apply another exception, namely the one laid down in point (a) of the first subparagraph of Article 4(2) of that directive in respect of the confidential ‘proceedings’ of a public authority.

19

In that regard, the High Court notes that, under the second subparagraph of Article 4(2) of Directive 2003/4, the disclosure of documents relating to ‘information on emissions into the environment’ may not be refused. It observes that that provision limits the applicability of a number of exceptions, as laid down in the first subparagraph of Article 4(2) of that directive, in the event of requests for access to environmental information, including the exception laid down in respect of the ‘proceedings of public authorities’. By contrast, it notes that that provision does not apply to the exception laid down in respect of ‘internal communications’.

20

Accordingly, the referring court takes the view that, if the documents whose disclosure is requested fell not within the latter exception, but within the one laid down in respect of ‘proceedings’, their disclosure would be mandatory at least in so far as they relate to ‘emissions into the environment’. It observes that, should that be the case, the Government of Ireland could not rely on the confidentiality of its meetings.

21

The referring court considers that meetings of the Government could constitute confidential ‘proceedings’. Thus, it notes that, in accordance with Article 28(4) of the Constitution of Ireland, the Government is to meet ‘as a collective authority’, and states that the purpose of those meetings, as identified by the Supreme Court of Ireland in the case of Attorney General v. Hamilton [1993] 2 I.R. 250, is to allow for full, free and frank discussion prior to the making of decisions.

22

However, it takes the view that Article 4 of Directive 2003/4 does not clearly indicate the dividing line between ‘internal communications’ and confidential ‘proceedings’.

23

In addition, the referring court observes that it is not certain, in the light of national law, that, in the context of the dispute in the main proceedings, Right to Know is entitled to challenge the characterisation of the documents in question as ‘internal communications’, as adopted in the judgment of 1 June 2018.

24

According to the referring court, this relates to an issue of law that was finally settled by the judgment of 1 June 2018, which, moreover, was not appealed. Furthermore, it observes that the dispute in the main proceedings is between the same parties, namely Right to Know and the Prime Minister, and has the same subject matter as the dispute which gave rise to that judgment, namely the handling of the request for access to environmental information of 8 March 2016. It considers that, accordingly, the res judicata in principle acquired by the judgment of 1 June 2018 would normally preclude Right to Know from being entitled to claim that the documents sought do not fall within the ground for refusal of access provided for in respect of ‘internal communications’.

25

The referring court states that that form of res judicata, known in Irish law as ‘issue estoppel’, extends beyond the operative part of the earlier judgment to include the grounds of that judgment which dealt with issues of fact and of law.

26

In its view, however, the courts retain a discretion to allow an issue to be reagitated where it is in the interests of justice to do so. It states that, in that context, the courts must seek to strike a balance between the competing rights of the parties, and, more generally, between the right of access to the courts and the public interest in the finality of litigation. In the present case, the referring court takes the view that an appropriate balance may be achieved if Right to Know were allowed to put forward its arguments relating to the characterisation of the documents which it seeks. It observes, moreover, that it would be in the public interest to address that particularly significant issue of law.

27

However, the referring court considers that a strict application of the principle of issue estoppel, which the respondent in the main proceedings seeks, also cannot be precluded. It states that such application could be compatible with EU law, even if it turns out that the judgment of 1 June 2018 is based on a misinterpretation of Article 4 of Directive 2003/4.

28

In its view, it is apparent, inter alia, from the judgment of 16 March 2006, Kapferer (C‑234/04, EU:C:2006:178), that, subject to the principles of equivalence and effectiveness, EU law does not require a national court to disapply domestic rules of procedure conferring finality on a decision, even if to do so would enable it to remedy an infringement of EU law. It notes that the rationale for that approach is to ensure both the stability of legal relations and the sound administration of justice.

29

According to the referring court, in this instance, the stability of legal relations is not a particularly valid justification, since the judgment of 1 June 2018 reserved the decision on Right to Know’s request, while at the same time quashing the decision of 27 June 2016 refusing access. Furthermore, it observes that, in those circumstances, Right to Know cannot be criticised for not appealing that judgment and for having raised a ground of challenge alleging misapplication of Article 4 of Directive 2003/4 solely in the context of the dispute in the main proceedings, namely the incorrect characterisation of the requested documents as internal communications within the meaning of point (e) of the first subparagraph of Article 4(1) of that directive.

30

In the light of those considerations, the referring court seeks to ascertain whether the principle of issue estoppel constitutes a form of res judicata which is permitted under EU law. In addition, it asks whether the strict application of that principle may be contrary to the principle of effectiveness where it leads to a situation in which an infringement of EU law can no longer be pleaded.

31

In those circumstances, the High Court decided to stay the proceedings and to refer the following questions to the Court of Justice for a preliminary ruling:

32

By its first question, the referring court asks, in essence, whether Article 4 of Directive 2003/4 is to be interpreted as meaning that records of formal meetings of the government of a Member State fall within the exception to the right of access to environmental information laid down in point (e) of the first subparagraph of Article 4(1) of that directive in respect of ‘internal communications’, or within the exception laid down in point (a) of the first subparagraph of Article 4(2) of that directive in respect of the ‘proceedings of public authorities’.

33

In that regard, it should be noted that, in adopting Directive 2003/4, the EU legislature intended to ensure the compatibility of EU law with the Aarhus Convention by providing for a general scheme to ensure that any applicant within the meaning of Article 2(5) of that directive has a right of access to environmental information held by or on behalf of the public authorities, without having to state an interest (judgment of 20 January 2021, Land Baden-Württemberg (Internal communications), C‑619/19, EU:C:2021:35, paragraph 28 and the case-law cited).

34

According to settled case-law, the right of access to environmental information provided for under Directive 2003/4 means that the disclosure of such information should be the general rule and that public authorities should be permitted to refuse a request for environmental information only in specific and clearly defined cases. The exceptions to the right of access should, consequently, be interpreted in a restrictive way, whereby the public interest served by disclosure should be weighed against the interest served by the refusal (see, to that effect, judgment of 20 January 2021, Land Baden-Württemberg (Internal communications), C‑619/19, EU:C:2021:35, paragraph 33 and the case-law cited).

35

Article 4 of that directive specifically sets out the exceptions which Member States may establish to the right of access to environmental information. In so far as such exceptions have in fact been transposed into national law, it is permissible for the public authorities to rely upon them in order to oppose requests for information that they receive (judgment of 20 January 2021, Land Baden-Württemberg (Internal communications), C‑619/19, EU:C:2021:35, paragraph 31).

36

Thus, Member States may, pursuant to point (e) of the first subparagraph of Article 4(1) of Directive 2003/4, provide for a request for environmental information to be refused if it concerns ‘internal communications’, taking into account, however, the public interest served by disclosure.

37

As regards the concept of ‘internal communications’, the Court has held that the word ‘communication’ relates to information addressed by an author to someone, an addressee who or which may be an abstract entity – such as ‘members’ of an administration or the ‘executive board’ of a legal person – or a specific person belonging to that entity, such as a member of staff or an official (judgment of 20 January 2021, Land Baden-Württemberg (Internal communications), C‑619/19, EU:C:2021:35, paragraph 37).

38

As regards the word ‘internal’, it relates to information which does not leave the internal sphere of a public authority, in particular when it has not been disclosed to a third party or been made available to the public (judgment of 20 January 2021, Land Baden-Württemberg (Internal communications), C‑619/19, EU:C:2021:35, paragraph 42).

39

Where a public authority holds environmental information that it has received from an external source, that information may also be ‘internal’ if it was not or should not have been made available to the public before that authority received it and it does not leave that authority’s internal sphere after it received it (judgment of 20 January 2021, Land Baden-Württemberg (Internal communications), C‑619/19, EU:C:2021:35, paragraph 43).

40

The concept of a ‘public authority’ is defined in Article 2(2) of Directive 2003/4. It means, inter alia, ‘government’ and ‘other public administration’.

41

In the present case, the request for access relates to records of government discussions which, according to the information available to the Court, are, in principle, capable of falling within the concept of ‘internal communications’. Subject to matters to be determined by the referring court, in the first place, such records reflect information exchanged between members of an administration and therefore of a ‘public authority’; in the second place, in so far as they are distributed within that administration, they involve ‘communications’; and, in the third and last place, in view of their confidential nature as provided for under point 3 of Article 28(4) of the Constitution of Ireland, those records are not intended to be disclosed to the public and therefore retain their ‘internal’ character.

42

In addition, pursuant to point (a) of the first subparagraph of Article 4(2) of Directive 2003/4, Member States may provide for a request for environmental information to be refused if disclosure of that information would adversely affect the confidentiality of the ‘proceedings of public authorities’, where such confidentiality is provided for by law.

43

As regards the concept of ‘proceedings of public authorities’, the Court has held that the term ‘proceedings’ refers to the final stages of the decision-making process of public authorities which are clearly defined as proceedings under national law and the confidentiality of which must be provided for by law (see, to that effect, judgment of 14 February 2012, Flachglas Torgau, C‑204/09, EU:C:2012:71, paragraphs 63 and 64).

44

In the present case, as regards records of government discussions, it is established that they fall within the rules on confidentiality provided for in point 3 of Article 28(4) of the Constitution of Ireland. By contrast, the request for a preliminary ruling does not enable the Court to determine whether the records which are the subject of Right to Know’s request for access reflect discussions that took place in the course of the final stage of a decision-making process which has been defined as proceedings under Irish law. If that were the case, which is a matter for the referring court to ascertain, such records would fall within the concept of ‘proceedings of public authorities’.

45

Accordingly, subject to matters to be determined by the referring court, it cannot be ruled out that, in this instance, both the conditions for applying the exception to the right of access laid down in point (e) of the first subparagraph of Article 4(1) of Directive 2003/4 and the conditions for applying the exception laid down in point (a) of the first subparagraph of Article 4(2) of that directive are satisfied.

46

In that regard, it should be noted that a cumulative application of those two exceptions is not possible.

47

Indeed, point (a) of the first subparagraph of Article 4(2) of Directive 2003/4 must be regarded as constituting a lex specialis in relation to point (e) of the first subparagraph of Article 4(1) of that directive. Thus, if the conditions for applying the more specific exception laid down in respect of the ‘proceedings of public authorities’ are in fact satisfied, the application of that exception takes precedence over that of the exception relating to internal communications, which is more general in scope.

48

Specifically, in addition to the conditions for applying the latter exception, namely, in essence, the transmission of information exclusively within the internal sphere of a public authority, the exception in respect of the ‘proceedings of public authorities’ applies only where the exchange of information takes place in the course of the final stage of a decision-making process which is clearly defined as ‘proceedings’ and the confidentiality of which is provided for by law.

49

Moreover, the two exceptions correspond to two separate legal regimes.

50

The protection of ‘internal communications’ allows a protected space to be created for public authorities in order to engage in reflection and to pursue internal discussions. That exception has a particularly broad scope, and it is capable of applying at each stage throughout the work carried out by those authorities. It follows that, in order to determine whether the refusal to grant access to information falling within that exception is justified, the weighing of the interests involved, namely those which oppose disclosing that information and those which justify disclosing it, must be tightly controlled (see, to that effect, judgment of 20 January 2021, Land Baden-Württemberg (Internal communications), C‑619/19, EU:C:2021:35, paragraphs 50, 58 and 60).

51

By contrast, the exception relating to the ‘proceedings of public authorities’ applies only to information exchanged in a very specific context. It allows Member States to protect solely information relating to the final stages of the decision-making process of public authorities and in respect of which they consider that such information, by virtue of its particularly sensitive nature, must be confidential. Therefore, the scope of that exception is precise and limited.

52

Furthermore, the EU legislature established a derogation from the exception laid down in point (a) of the first subparagraph of Article 4(2) of Directive 2003/4, in order to exclude expressly from that exception certain information of particular importance to the public. Thus, in accordance with the last sentence of the second subparagraph of Article 4(2) of that directive, the exception provided for in respect of the ‘proceedings of public authorities’ does not allow a request for access to environmental information concerning ‘information on emissions into the environment’ to be refused.

53

Accordingly, where a Member State has transposed point (a) of the first subparagraph of Article 4(2) of that directive and where the information whose disclosure is requested has actually been exchanged in the course of confidential proceedings, in such a manner that that information falls within the scope of that provision, it is for the competent national authorities to ascertain whether such information relates to emissions into the environment. Should that be the case, even if the abovementioned information is, in principle, regarded as confidential under national law, access to it cannot be refused, unless it is impossible to separate it out from the rest of the information exchanged in the same context (see, to that effect, judgment of 23 November 2016, Bayer CropScience and Stichting De Bijenstichting, C‑442/14, EU:C:2016:890, paragraph 105).

54

Where it appears that the information sought does not relate to emissions into the environment, the competent national authorities must, in accordance with the second sentence of the second subparagraph of Article 4(2) of Directive 2003/4, weigh the public interest served by disclosure of that information against the interest served by the refusal to disclose it.

55

Such weighing of the interests involved is also required where, if the exception in respect of the ‘proceedings of public authorities’ is not applicable, the exception in respect of internal communications, as laid down in point (e) of the first subparagraph of Article 4(1) of Directive 2003/4, applies (see, to that effect, judgment of 20 January 2021, Land Baden-Württemberg (Internal communications), C‑619/19, EU:C:2021:35, paragraph 58).

56

Lastly, it should be recalled that, in accordance with Article 4(4) of Directive 2003/4, the competent national authority must always establish whether some of the information sought may be separated out from the information covered by the applicable exception to the right of access, with the result that it may make partial disclosure (see, to that effect, judgment of 20 January 2021, Land Baden-Württemberg (Internal communications), C‑619/19, EU:C:2021:35, paragraph 66).

57

Having regard to all the foregoing considerations, the answer to the first question is that Article 4 of Directive 2003/4 must be interpreted as meaning that:

58

As a preliminary point, it should be noted that the dispute in the main proceedings concerns a request for access to environmental information which falls within the scope of Directive 2003/4. Hearing an action brought against the decision of 27 June 2016 by which that request was refused, the High Court held, by judgment of 1 June 2018, that the exception to the right of access laid down in point (e) of the first subparagraph of Article 4(1) of Directive 2003/4 in respect of internal communications of a public authority was applicable, and then remitted the case to the Prime Minister so that the latter could weigh the public interest served by disclosure against the interest served by the refusal to disclose.

59

A new decision, adopted on 16 August 2018, granted in part the request for access. That decision is the subject of the dispute in the main proceedings in which Right to Know submits that it was necessary to apply not the exception to the right of access laid down in respect of ‘internal communications’, but rather the exception laid down in point (a) of the first subparagraph of Article 4(2) of Directive 2003/4 in respect of the ‘proceedings of public authorities’.

60

In the referring court’s view, the latter exception may indeed be applicable. If so, it considers that the exception laid down in respect of internal communications would have to be disregarded.

61

However, the referring court explains that the res judicata acquired by the grounds of the High Court judgment of 1 June 2018 could preclude such an approach, in so far as, in that judgment, that court found that the exception laid down in respect of ‘internal communications’ was applicable. It takes the view that that issue would normally have to be regarded as having been finally settled between the parties and therefore could no longer be called into question. Consequently, the referring court considers that, in order to settle the dispute in the main proceedings, it must rule on whether the scope afforded to the principle of res judicata under Irish law is compatible with EU law.

62

In that regard, attention should be drawn to the importance, both in the legal order of the European Union and in national legal systems, of the principle of res judicata. In order to ensure stability of the law and legal relations, as well as the sound administration of justice, it is important that judicial decisions which have become final after all rights of appeal have been exhausted or after expiry of the time limits provided for in that regard can no longer be called into question (judgment of 7 April 2022, Avio Lucos, C‑116/20, EU:C:2022:273, paragraph 92 and the case-law cited).

63

Therefore, EU law does not require a national court to disapply domestic rules of procedure conferring the authority of res judicata on a judgment, even if to do so would make it possible to remedy a domestic situation which is incompatible with EU law (judgment of 7 April 2022, Avio Lucos, C‑116/20, EU:C:2022:273, paragraph 93 and the case-law cited).

64

Thus, EU law also does not require a national judicial body automatically to go back on a judgment having the force of res judicata in order to take into account the interpretation of a relevant provision of EU law adopted by the Court (judgment of 7 April 2022, Avio Lucos, C‑116/20, EU:C:2022:273, paragraph 94 and the case-law cited).

65

In addition, it is apparent from the Court’s case-law that, in the absence of EU legislation in this area, the rules implementing the principle of res judicata are a matter for the national legal order, in accordance with the principle of the procedural autonomy of the Member States. Those rules must not, however, be less favourable than those governing similar domestic situations (the principle of equivalence) nor may they be framed in such a way as to make it in practice impossible or excessively difficult to exercise the rights conferred by the EU legal order (the principle of effectiveness) (judgment of 7 April 2022, Avio Lucos, C‑116/20, EU:C:2022:273, paragraph 100 and the case-law cited).

66

As regards the latter principle, it should be recalled that Article 47 of the Charter of Fundamental Rights of the European Union enshrines the right to an effective remedy before an impartial tribunal (judgment of 6 October 2015, East Sussex County Council, C‑71/14, EU:C:2015:656, paragraph 52 and the case-law cited).

67

That right is also reflected in Article 6 of Directive 2003/4. By contrast, neither that article nor the other provisions of that directive contain rules relating to the implementation of the principle of res judicata.

68

Therefore, it must be held that, by its second, third and fourth questions, which it is appropriate to examine together, the referring court asks, in essence, whether Article 6 of Directive 2003/4, read in the light of the principles of equivalence and effectiveness, is to be interpreted as precluding a national rule according to which the principle of res judicata prevents a person, who, in a first judgment, obtained the quashing of a decision which had refused his or her request for access to environmental information, from raising, in the context of a dispute between the same parties concerning the legality of a second decision which relates to the same request for access and was adopted in order to give effect to the first judgment, a ground of challenge alleging an infringement of Article 4 of Directive 2003/4, where that ground of challenge was rejected in the first judgment but such a rejection is not referred to in the operative part of that judgment, and where that judgment became final in the absence of any appeal brought by the applicant seeking access.

69

It should be recalled at the outset that, with regard to the principle of effectiveness, the Court has held that every case in which the question arises as to whether a national procedural provision makes the application of EU law impossible or excessively difficult must be analysed by reference to the role of that provision in the procedure, its operation and its particular features, viewed as a whole, before the various national bodies. For those purposes, account must be taken of the basic principles of the domestic judicial system, such as protection of the rights of the defence, the principle of legal certainty and the proper conduct of procedure (see, to that effect, judgment of 7 April 2022, Avio Lucos, C‑116/20, EU:C:2022:273, paragraph 101 and the case-law cited).

70

In the present case, no information in the file before the Court leads to the conclusion that there are no legal remedies in the Irish legal order which effectively guarantee the protection of the rights that individuals derive from Directive 2003/4.

71

On the contrary, as is apparent from the wording of the third question, read in the light of the information contained in the order for reference, in the proceedings before the High Court, as a result of which that court delivered the judgment of 1 June 2018, Right to Know was able to plead an infringement of Article 4 of Directive 2003/4, and the High Court examined that ground of challenge. In particular, that court rejected the argument put forward by Right to Know seeking a declaration that the information sought fell within the exception to the right of access to environmental information laid down in point (a) of the first subparagraph of Article 4(2) of Directive 2003/4, a fact which Right to Know and the Prime Minister confirmed in their written observations submitted to the Court.

72

In those circumstances, it must be held that, in so far as the grounds of the High Court judgment of 1 June 2018 relating to the inapplicability of the latter provision have the force of res judicata under Irish law, that law did not undermine the effectiveness of EU law (see, by analogy, judgment of 24 October 2018, XC and Others, C‑234/17, EU:C:2018:853, paragraphs 55 to 57).

73

That finding cannot be invalidated by the fact that, in the proceedings as a result of which the judgment of 1 June 2018 was delivered, the High Court did not make a reference for a preliminary ruling to the Court of Justice on the basis of Article 267 TFEU.

74

In that regard, Article 267 TFEU gives national courts the widest discretion in referring matters to the Court if they consider that a case pending before them raises questions involving the interpretation of provisions of EU law, or consideration of their validity, which are necessary for the resolution of the case before them. National courts thus have the power and, in certain cases, an obligation, to make a reference for a preliminary ruling once they find, either of their own motion or at the request of the parties, that the substance of the dispute involves a question to be resolved which falls within the scope of the first paragraph of that article (judgment of 30 April 2020, Blue Air – Airline Management Solutions, C‑584/18, EU:C:2020:324, paragraph 38 and the case-law cited).

75

Furthermore, individuals who, due to a decision of a court adjudicating at last instance, have suffered damage as a result of an infringement of rights which are conferred on them by EU law, may hold that Member State liable, provided that the conditions relating to the sufficiently serious nature of the breach and to the existence of a direct causal link between that breach and the loss or damage sustained by those individuals are satisfied (judgment of 7 July 2022, F. Hoffmann-La Roche and Others, C‑261/21, EU:C:2022:534, paragraph 58 and the case-law cited).

76

By contrast, recognition of the principle of State liability for a decision of a court adjudicating at last instance does not in itself have the consequence of calling into question that decision as res judicata. In any event, the principle of State liability inherent in the EU legal order requires reparation of the damage incurred, but not revision of the judicial decision which was responsible for the damage (see, to that effect, judgments of 30 September 2003, Köbler, C‑224/01, EU:C:2003:513, paragraph 39, and of 9 September 2015, Ferreira da Silva e Brito and Others, C‑160/14, EU:C:2015:565, paragraph 55).

77

Therefore, the failure of a court adjudicating at last instance to fulfil its obligation to make a reference for a preliminary ruling and, a fortiori, the absence of such a reference in proceedings before a court that does not adjudicate at last instance cannot entail an obligation to disregard the res judicata of court decisions.

78

That said, if the applicable domestic rules of procedure provide for the possibility, under certain conditions, for a national court to go back on a decision having the force of res judicata in order to render the situation compatible with national law, that possibility must prevail if those conditions are satisfied, in accordance with the principles of equivalence and effectiveness, so that the situation at issue in the main proceedings is brought back into line with EU law (see, to that effect, judgment of 10 July 2014, Impresa Pizzarotti, C‑213/13, EU:C:2014:2067, paragraph 62).

79

In that regard, it is apparent from point 54 of the Advocate General’s Opinion that, in special circumstances, Irish courts in fact have discretion to allow a party to a dispute to pursue an issue that has already been decided against that party in earlier proceedings, which is a matter for the referring court to ascertain.

80

Where appropriate, and in so far as, in the present case, the conditions stipulated under Irish law for the exercise of such discretion are satisfied, the referring court is required to exercise that discretion if it finds that, contrary to what is stated in the High Court judgment of 1 June 2018, the information sought does not fall within the exception to the right of access to environmental information laid down in respect of ‘internal communications’.

81

Moreover, as the Advocate General noted, in essence, in points 56 to 58 of her Opinion, it appears that, under the Irish legal system, the fact that a party did not have the possibility to appeal a judgment containing a finding which has the force of res judicata may prove to be relevant for the purposes of exercising the abovementioned discretion. It is therefore for the referring court to ascertain whether Right to Know in fact had the possibility to appeal the finding made in the High Court judgment of 1 June 2018 according to which the request for access to environmental information of 8 March 2016 was covered by the exception relating to ‘internal communications’. If that is not the case, the principles of equivalence and effectiveness require the referring court to exercise its discretion.

82

Having regard to all the foregoing considerations, the answer to the second, third and fourth questions is that Article 6 of Directive 2003/4, read in the light of the principles of equivalence and effectiveness, must be interpreted as not precluding a national rule according to which the principle of res judicata prevents a person, who, in a first judgment, obtained the quashing of a decision which had refused his or her request for access to environmental information, from raising, in the context of a dispute between the same parties concerning the legality of a second decision which relates to the same request for access and was adopted in order to give effect to the first judgment, a ground of challenge alleging an infringement of Article 4 of Directive 2003/4, where that ground of challenge was rejected in the first judgment but such a rejection is not referred to in the operative part of that judgment, and where that judgment became final in the absence of any appeal which could have been brought by the applicant seeking access. However, to the extent that it is authorised to do so by the applicable domestic rules of procedure, a national court must allow that person to raise the abovementioned ground of challenge so that, if necessary, the situation at issue in the main proceedings is brought back into line with EU legislation.

83

Since these proceedings are, for the parties to the main proceedings, a step in the action pending before the referring court, the decision on costs is a matter for that court. Costs incurred in submitting observations to the Court, other than the costs of those parties, are not recoverable.

On those grounds, the Court (Fourth Chamber) hereby rules: