Diagnostic services as ‘treatment’ under Article 18 of the Social Security Co-Ordination Protocol (EU-UK)? – Court of Appeal in Northern Ireland ([2024] NICA 53)

This case contains the first binding ¹ decision by a UK Court of Appeal — here, the Northern Ireland Court of Appeal — on a claim for authorisation of treatment abroad under the EU–UK Social Security Co-ordination Protocol (SSC). While dismissing the appeal due to the subsequent loss of legal interest as ‘academic’ under the Salem principle, the Court of Appeal provided a detailed obiter dictum on the interpretation of Article 18 SSC. ² The judgment addresses not only the substantive question of whether diagnostic services are covered by the term ‘treatment’ in Article 18 SSC, but also the procedural question of the extent to which UK courts may rely on ECJ case law when interpreting the Protocol after Brexit.

The factual and legal setting of the case can be summarised as follows. The UK claimant was referred to the Neurology Service at the South Eastern Health and Social Care Trust under the NHS in 2017 for suspected multiple sclerosis, which was later confirmed as Fibromyalgia. After being placed on a waiting list, a neurological appointment was promised within 163 weeks. In 2021, amid the lengthy wait, the claimant sought medical treatment abroad under the S2 scheme. However, the claim was later denied due to the lack of prior neurological diagnosis.

The S2 scheme is originally based on Article 20 of the Regulation 883/2004, which sets out the rules for travelling to another EU Member State for the purpose of receiving benefits in kind (appropriate treatment). The SSC, which is relevant in this procedure, forms part of the Trade and Cooperation Agreement. This came into force on 1 May 2021 and regulates the UK's relationship with the EU following Brexit. Article 18 of the SSC is modelled ³ on Article 20 of Regulation 883/2004, differing only in replacing the term ‘Member State’ with ‘State’ and in using gender-neutral language (‘his’/‘he’ vs. ‘their’/‘that person’). However, the additional exclusions of benefits set out in Article 3(4) of the SSC should be noted. In the area of sickness benefits, as mentioned and defined in Articles 3(1)(a) and 1(va)(i) of the Regulation 883/2004, this concerns assisted reproduction services and long-term care benefits listed in Part 2 of Annex SSC-1. With this latter exclusion, the UK effectively re-establishes ⁴ its legal position regarding the non-exportability of long-term care cash benefits, thereby neutralising the practical effect of an opposite ECJ ruling ⁵ from 2007. Pursuant to Article 67 of the SSC in conjunction with Sec 26 of the European Union (Future Relationship) Act 2020, the rights arising from Article 18 of the SSC are part of the domestic law ⁶ and can be enforced in UK courts.

Reasoning both grammatically and systematically, the Court of Appeal ruled that ‘diagnosis’ is not included in the right to ‘treatment’ under Article 18 SSC. It noted that Article 18(2), sentence 1, of the SSC refers to ‘treatment appropriate to their condition’. This makes it clear that the first step is always to ascertain the applicant's condition, which must therefore precede the treatment itself. By contrast, including the diagnosis in the treatment claim ‘would effectively extinguish the manifestly sensible and reasonable division of functions and responsibilities as between the patient's home State and the host […] State concerned’. ⁷ According to the court, such an understanding would render the second sentence of Article 18(2) of the SSC meaningless. This ‘sentence categorically reinforces the construction that the vital, indispensable first step in the exercise will invariably be the diagnosis of the patient's “condition”.’ ⁸ This understanding emphasises that the SSC also maintains a functional division between the State of residence, which remains responsible for determining the patient's condition, and the State of treatment, which is confined to providing the authorised care.

Interestingly, in its reasoning the Court of Appeal referred to the ECJ's considerations in two comparable cases. In the case of A v Latvijas Republikas Veselibas Ministrija (2021), the ECJ clarified that ‘the essential aim of “sickness benefits” within the meaning of that provision is the patient's recovery […] by securing the care which his or her condition requires’. ⁹ In WO v Vas Megyei Kormanyhivatal (2020), the Court gave specific consideration to the definition of ‘scheduled treatment’ in Article 20 of Regulation 883/2004, holding that ‘the receipt of such treatment is […] subject to the granting of an authorisation by the Member State of residence’. ¹⁰ Regarding this authorisation, Article 26 of Regulation 987/2009 (which corresponds to Article 20 of Regulation 883/2004) refers in principle to doctors authorised in that state. The Court of Appeal also correctly pointed out that the substantive legal classification of a diagnosis was not a matter for the two ECJ rulings. An opposing statement by the EU Commission, which stated that ‘a medical diagnosis […] can be considered a sickness benefit in kind covered by Article 18 of Regulation (EC) No 883/2004’, ¹¹ was dismissed by the Court of Appeal on the grounds that it was legally non-binding. However, it cannot be concluded from this that the diagnosis falls without exception within the responsibility of the competent state. Firstly, the ECJ has clarified, in the Keller (2005) and Casa Naţională de Asigurări de Sănătate and Casa de Asigurări de Sănătate Constanţa (2021) cases, that a medical diagnosis originating in the State of treatment — whether in the context of a second-opinion procedure or in the course of authorised care under Article 20(2) of the Regulation 883/2004 — may not be disregarded by the competent institution. ¹² Secondly, the Court of Appeal's reliance on ‘elementary common sense and reason', ¹³ arguably underestimates the extent to which diagnostic capacity can become a structural bottleneck. Where timely diagnosis is not realistically available in the State of residence, an overly narrow understanding of the term ‘treatment’ risks undermining the protective effect of the coordination framework. Finally, a diagnosis undertaken for medical purposes is not merely a procedural precondition for authorisation under Article 18 SSC. It also typically forms part of the healthcare services provided in the State of residence, even if it is not conceptualised as ‘treatment’ in the strict sense.

As the application for benefits under the S2 scheme was initially made in 2021, this case fell within the period following the Brexit transition, which ended on 31 December 2020 (Article 126 EU–UK Withdrawal Agreement (WA)). Consequently, the provisions of Articles 30 et seq. of the WA (Title III: ‘Coordination of Social Security Systems’) did not apply. Thus, only the SSC Protocol was relevant. Nevertheless, the Northern Ireland Court of Appeal was able to ‘consider’ ¹⁴ the aforementioned ECJ rulings not only as general persuasive authority, but on the basis of section 6(2) of the UK European Union (Withdrawal) Act 2018. Although the section heading suggests that this mechanism is restricted to ‘assimilated EU law’, the scope of the norm is not ¹⁵ limited to ‘retained EU law’, to which the SSC does not belong. According to section 6(2) of the UK European Union (Withdrawal) Act 2018, ‘a court or tribunal may have regard to anything done on or after the [… Brexit transition period] by the European Court, another EU entity or the EU so far as it is relevant to any matter before the court or tribunal.’ ¹⁶ The application of this principle could help to ensure that UK courts’ interpretation of the SSC does not differ ¹⁷ too much from the ECJ's understanding of equivalent EU social security rules in the future.

In contrast, in ‘legacy cases’ where UK citizens were subject to EU law (or vice versa) at the end of the transition period (Article 30 WA), the EU coordination framework (Regulations 883/2004 and 987/2009) continues to apply pursuant to Article 31(1) of the WA. According to Article 39 of the WA, this framework is designed to protect eligible individuals for their entire lifetime, provided they continue to meet the relevant conditions without interruption. Therefore, the competent authorities must prepare for a very long dual regulatory period, ¹⁸ during which they must not only examine the substantive legal requirements of the coordination provisions, but also the individual circumstances at the end of the transition.

The institutional and remedial effects of the WA differ significantly from those of the SSC. Under the WA, which includes all benefits referred to the Regulation 883/2004, ¹⁹ individuals from both the EU and the UK can directly invoke provisions, ²⁰ and the UK authorities must disapply (Article 4(2) WA) conflicting domestic regulations. Furthermore, the provisions of this agreement referring to Union law or to concepts or provisions thereof shall be interpreted and applied in accordance with the methods and general principles of EU Law (Article 4(3) WA). From the EU perspective, the WA is part of the Union's legal order (Article 216(2) TFEU), ²¹ meaning that national courts can refer cases to the ECJ under Article 267 TFEU. From a UK point of view, Article 158(1) of the WA permits courts to refer questions to the ECJ for a preliminary ruling in cases initiated in a UK court within eight ²² years of the end of the transition period (until 31 December 2028) in order to maintain consistent ²³ interpretation. This procedure corresponds in substance to that under Article 267 TFEU. After this period, there is a risk of divergent interpretations of the still applicable WA provisions. ²⁴

Most recently, in the AF v Guvernul României and Others case (2025), the ECJ considered issues that were at least partly similar to those in the Northern Ireland Court of Appeal case. ²⁵ Among other things, the case concerned the admissibility of national provisions linking the right to reimbursement of costs to a prior medical examination by a health professional belonging to the public health (insurance) system of the country of origin. However, unlike in the UK case, the ECJ's decision focused primarily on the conditions for recognising a medical assessment for subsequent reimbursement claims under Article 7(7) of Directive 2011/24/EU rather than on the question of whether diagnostic services themselves could be performed abroad under Article 20(2) of Regulation 883/2004. ²⁶ Furthermore, the ECJ based its decision predominantly on EU primary law considerations in the context of the freedom to provide services which most likely cannot be transferred to the post-Brexit situation.