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22 March 2023

Constitutional Identity, Ireland and the EU

The Irish Supreme Court Ruling Costello v. Government of Ireland

Costello v. Government of Ireland and others is one of the most significant recent Irish Supreme Court rulings concerning EU law. The case involved a member of parliament seeking to restrain the Irish government from ratifying the 2014 EU-Canada Comprehensive Economic and Trade Agreement (CETA) on grounds of alleged unconstitutionality. Costello’s claim failed in the High Court in September 2021. However, the Supreme Court granted leave for an appeal (leapfrogging the Court of Appeal) because the case raised important domestic and EU law issues. It ruled 4-3 in favour of Costello on 11 November. Costello is a lengthy ruling: the original texts amounted to an impressive 474 pages, with all seven judges producing his/her own judgment

Costello’s most long-lasting impact is likely to be its introduction of the concept of constitutional identity into Irish constitutional jurisprudence. As is well known, this began life in Karlsruhe: with the doctrine gathering pace in the Bundesverfassungsgericht’s 2009 Lisbon ruling, in which it produced a lengthy list of Staatsaufgaben that it deemed necessary the State not transfer to EU level. Prior to the Supreme Court ruling in Costello, constitutional identity was not a concept that had featured in Irish jurisprudence at all. This blog concerns the implications of its introduction in Costello.

The seven Supreme Court judgments fall into three categories. The first clearly recognised constitutional identity as a new concept. Thus Hogan J. (a former Advocate General in the Court of Justice) clearly regard constitutional identity as a concept going beyond mere sovereignty, discussing measures “which ensured that the constitutional identity of the State and its sovereignty [were] thereby safeguarded.” His judgment identified democracy as a facet of constitutional identity, noting that by the declaration in Article 5 of the Irish Constitution (Bunreacht) that the State is sovereign and democratic, democracy was “made an indispensable feature of the very constitutional identity of the state.”

For Hogan J. – although his views in this regard did not secure the support of the majority of the Court – any amendments to CETA, which included for him CETA Joint Committee interpretive decisions, thus required the approval of the Dáil (lower House) under Article 29.5.2 of the Bunreacht, even though once adopted CETA would form part of EU law. They would not seemingly benefit from the Bunreacht’s Article 29.4.6° immunity clause for EU measures. For Hogan J. therefore, both conceptually and in terms of its legal significance, constitutional identity appeared novel.

He viewed constitutional identity as encompassing “the legislative and juridical autonomy of the State” and moreover viewed constitutional identity as open-ended, “a category…perhaps, never closed”.

Interestingly, the lead minority opinion, that of Chief Justice O’Donnell CJ, was very similar in many regards. Thus, for example, according to O’Donnell J., “no judgment could be enforceable in this jurisdiction where such enforcement was contrary to the constitutional identity of the State”.

Other judges however, deployed the concept without stipulating unambiguously that constitutional identity had implications going beyond those of sovereignty as traditionally understood. In these judgments, ‘sovereignty’ and ‘constitutional identity’ seemed to be used more or less interchangeably. Hence, Dunne J. (in the majority) hardly referred to constitutional identity. McMenamin J. (in dissent) asserted that (apparently all of) what is provided in both Article 5 and Article 6 of the Bunreacht is “part of the Constitutional identity of the State”. These articles stipulate that Ireland is a sovereign, independent, democratic state, that powers of Government derive from the People and that these powers are exercisable only by, or by the authority of the organs of the Irish State. This seems an extraordinarily broad definition to give to constitutional identity. McMenamin J. asserted that “were it to be found that some action or actions, or decisions on foot of CETA did offend against fundamental constitutional values or the constitutional identity of the State… a court… would have no alternative but to refuse such an award” and that “were it to be shown that there was an alienation of sovereignty, without specific constitutional amendment…then Article 29.4.6° (the Bunreacht’s EU immunity clause) could provide no answer. Overall, McMenamin’s judgment is striking for the absence of any dividing line between sovereignty and constitutional identity issues.

Power J.’s judgment (in dissent) also showed ambivalence, although she did search in her judgment for the parameters of constitutional identity in a way indicative of a desire to define a new concept.

Two judges, both in the majority, made no explicit reliance on constitutional identity. Baker J. neither referred to nor relied on it. Charleton J.’s judgment admitted of no exception to the duty to enforce EU law. For him, when CETA was “ratified and brought into law…the Treaty will be a necessary part of Ireland’s duty of fidelity and cooperation.” As far as Charleton J. was concerned, “in Ireland the discretion, on constitutional grounds, for refusing to enforce what are likely to be gigantic [CETA tribunal] awards is so vanishingly small as to be reduced to nothing.” Reliance on “any grounds as to our constitutional tradition” as grounds to deny enforcement of an award by a CETA investment tribunal was consonant neither with EU law nor with Art. 29.4 (the Bunreacht’s Europe clause).

Some Observations

Constitutional identity as seen in Costello originated differently to constitutional identity in German law (where constitutional identity was conceived as a limit to European integration). In Costello, it was instead conceived of as a limit to an international treaty regime which in turn was seen as carrying risks for national legal systems and the EU legal system alike. The Court in Costello responded in particular to the potential danger of perverse CETA tribunal decisions and the existence of a legal requirement to enforce these. Hogan J. expressed concerns not merely for Irish constitutional identity but also for the EU legal order (citing the risk of a CETA Tribunal refusing to follow a material decision of the ECJ). O’Donnell CJ’s opinion was very similar. Neither judgment evinced hostility to European integration. This does not guarantee that constitutional identity, in Irish law will always be deployed in a way favourable to European integration, however. As in German law, it could develop into a potentially formidable legal obstacle. All depends on the course of future Irish case law in this regard, which is not predictable.

Striking in Costello was the wide agreement, in both majority and minority judgments, regarding the existence of the constitutional identity doctrine of in Irish law, notwithstanding the lack of any mention of such a concept either in the Bunreacht’s text or earlier case-law. On one level, it is surprising to see a heretofore unknown doctrine such as constitutional identity simply appear in the Irish legal landscape. The willingness of the Court to imply such a significant concept into the Constitution contrasts strikingly with its long-standing reluctance to expand the gamut of implied constitutional rights enjoyed by the citizen for fear of trespassing on legislative role. Hence in the 2020 case Friends of the Irish Environment CLG v. Government of Ireland and others, then-Chief Justice Clarke declined to recognise an unenumerated right to an environment consistent with human dignity ( a right recognised in many other jurisdictions) and objected even to the very use of the term “unenumerated” rights because it conveyed “an impression that judges simply identify rights of which they approve and deem them to be part of the Constitution”. He preferred the term “derived rights” as more appropriate, “for it conveys that there must be some root of title in the text or structure of the Constitution from which the right in question can be derived.” He grounded his approach to implied rights in the need to prevent judicial overreach, arguing that “what needs to be guarded against is allowing for a blurring of the separation of powers by permitting issues which are more properly political and policy matters (for the legislature and the executive) to impermissibly drift into the judicial sphere.” Contrast Costello, which marked a significant new judicial restriction on executive action on external affairs. Costello may come to mean that there are policy choices which can not, regardless of any decision of the Irish executive or legislature, ever be taken at EU level. It may possibly lead (somewhat analogously to the 1987 Crotty ruling) to future referendums.

Another jarring contrast to its implied rights case-law is that one struggles to find any ‘root of title’ in the Irish Constitution for the constitutional identity doctrine: as already noted, until Costello, the doctrine was unheard of in Irish constitutional law.

Finally, another strong contrast with rights jurisprudence is that the Supreme Court in Friends of the Irish Environment, in rejecting the existence of a constitutional right to a healthy environment, pointed to the “very vague” and “ill-defined” nature of such a right. This contrasts with the distinctly amorphous shape of constitutional identity, the scope of which produced no unanimity among the six judges who recognised it. In some rulings it was seen as having such an extraordinarily wide ambit as to make it seem inherently unfeasible that it can possibly form a workable limit either to the scope of the empowerment to join the EU conferred in Article 29.4 or the immunity granted by Article to acts of the EU and its institutions or to necessitated laws, acts and measures of the Irish State. A more complete and workable doctrine of constitutional identity remains something for future Irish courts to formulate.

What are the implications of the new doctrine? Notwithstanding the length and number of judgments, this was poorly teased out. Constitutional identity seemingly involves the idea that there may be areas of EU law which must now be regarded as falling outside the immunity from constitutional attack granted by Article 29.4.6° of the Irish Constitution both (a) to laws, acts and measures by the EU and its institutions and (b) to laws, acts and measures of the Irish State which are necessitated by membership. This is highly significant and one which could conceivably lead to a need for future referendums in respect of treaties agreed at EU level, even if it was held not to require any referendum in the case of CETA itself. Insofar as Costello involves the idea that there are policy choices which ought not as a matter of interpretation be regarded as having been authorised to be transferred to European level under Article 29.4.5°, it is equally significant.

Costello-style constitutional identity might well serve as a guardian of last resort against the possibility – however remote this might be – of being compelled to comply with a perverse ruling by a CETA tribunal. This should not however prevent us from simultaneously acknowledging that (a) the new doctrine sits uncomfortably with the orientation of other recent Supreme Court case-law in particular concerning unenumerated rights; that (b) the doctrine of state constitutional identity has no apparent basis in Irish precedent or written law; that (c) its scope remains either unclear or impracticably broad; and (d) its implications are also obscure, regarding in particular both the implicit constitutional terms of Ireland’s accession to the EU under Article 29.4.5° and the scope of the immunity clauses in Article 29.4.6°. Furthermore (e) the adoption of the constitutional identity clause is a very major potential judicial empowerment vis-à-vis the other branches of government, even if the absence of an Ewigkeitsklausel in the Irish Constitution means that the impact of state liability does not possess all the drastic potential it possesses in German constitutional law. In Ireland, no apparent obstacle exists to the amendment procedure being used to overcome any judicial interpretation of the Constitution. This leaves open the possibility that judicially-viewed transgressions of constitutional identity may be a constitutional obstacle to executive action (or action by international bodies) which it is possible to overcome through constitutional amendments, although it bears recalling that any such step would require a referendum.

It may be that the concept of constitutional identity will remain for the most part undeployed. In this regard, however, there can be no guarantees. An immensely powerful new judicial weapon has been forged by the Supreme Court in Costello. It remains to be seen how it will be used by future Irish Courts.

SUGGESTED CITATION  Barrett, Gavin: Constitutional Identity, Ireland and the EU: The Irish Supreme Court Ruling Costello v. Government of Ireland, VerfBlog, 2023/3/22,, DOI: 10.17176/20230322-185237-0.

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