Age-Based Succession to Tenancies, Article 40.1 Equality and the Form of Constitutional Challenges: Commentary on ZG & EW v Ireland & Attorney General [2025] IESC 49

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1. Introduction

This decision of the Supreme Court of Ireland sits at the intersection of housing law, constitutional equality, and procedural law. A tragic set of facts — the violent death of a single mother and the upheaval of her 14‑year‑old son’s living arrangements — was the vehicle for a far‑reaching judgment on:

• when age-based distinctions in legislation are constitutionally permissible under Article 40.1;
• the significance of Article 42A (children’s rights) and Article 40.5 (inviolability of the dwelling) in the context of landlord–tenant law; and
• the proper procedural route for direct constitutional challenges to Acts of the Oireachtas.

At its core, the case concerned whether Section 39(3)(a) of the Residential Tenancies Act 2004 (“RTA 2004”), as amended, is unconstitutional because it allows only certain adults, but not children under 18, to succeed to a Part 4 tenancy on the death of a tenant.

Chief Justice O’Donnell, delivering the judgment analysed here, dismissed the appeal. He upheld the constitutionality of the age-based cut‑off in Section 39(3)(a), clarified that the appropriate standard under Article 40.1 is a rationality test (not proportionality) for age distinctions of this kind, and stated that direct challenges to the validity of primary legislation should, in future, be brought by plenary proceedings, not judicial review.

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2. Background and Facts

2.1 The Family Circumstances

EW, the second applicant, is the minor son of a tenant in a Clúid Housing Association apartment. His mother, a single parent, had spent over 11 years seeking stable accommodation before obtaining a tenancy from Clúid in June 2022. EW was recorded as a permitted occupant.

In 2023, while on holiday abroad, EW’s mother was killed in tragic and violent circumstances. EW, then 14, went to live with his grandparents. His father was in his life but did not reside with him.

ZG, the first applicant and EW’s aunt, lived nearby and had a close relationship with him. She wished to assume responsibility for him and proposed to give up her own accommodation to move into the Clúid flat with EW. Initially, there was some suggestion EW’s grandparents might take the tenancy, but the proposal ultimately focused on ZG.

2.2 The Statutory and Policy Framework

(a) Part 4 Tenancies and Section 39 RTA 2004

The RTA 2004 introduced Part 4 tenancies, granting robust statutory security of tenure to tenants of most domestic dwellings after an initial qualifying period of occupation (initially 6 months). Over time, the duration of Part 4 tenancies has been extended:

• originally 4 years;
• extended to 6 years in 2016; and
• now of unlimited duration under s. 5 of the Residential Tenancies (Amendment) Act 2021.

Section 39 governs what happens to a Part 4 tenancy when the tenant dies:

• s. 39(1): as a general rule, the Part 4 tenancy terminates on the death of the tenant.
• ss. 39(2)–(3): this termination is disapplied if certain conditions are met, creating a statutory succession for particular persons living in the dwelling at the time of death.

Section 39(3)(a) sets out who may succeed to the tenancy. Succession lies only to:

• a spouse or civil partner;
• a cohabitant who meets a 6‑month cohabitation requirement;
• a child, stepchild, foster child or adopted child aged 18 years or more; or
• a parent of the deceased tenant,

provided that the dwelling was occupied by such person(s) at the time of death and one or more elect in writing to become the tenant(s).

Thus, children under 18 are categorically excluded from statutory succession. Moreover, siblings, grandparents and other relatives — even if resident — are not in the statutory class. Section 39 applies across the board, including to approved housing bodies such as Clúid (following the 2015 amendments extending the regime to social housing tenancies).

(b) Clúid’s Succession Policy

Clúid, as an approved housing body funded to provide social housing to persons with a demonstrated housing need, had its own limited succession policy. Relevant points were:

• A partner of the deceased tenant or an adult family member (over 18) who had resided in the dwelling for two years could succeed if:
  • assessed as eligible for social housing support;
  • nominated by the local authority; and
  • applied in writing.
• Clause 3.5 provided that if the tenant died leaving dependants, a relative with legal guardianship of the dependants could apply to become tenant, subject to the same criteria.

ZG did not satisfy these conditions: she had not lived in the flat, had not (at the time proceedings commenced) legal guardianship of EW, and had not herself been assessed as having a housing need. She also fell outside s. 39(3)(a), which does not include siblings and is limited to those in occupation at the tenant’s death.

2.3 The Proceedings

When it became apparent that Clúid proposed to recover possession of the flat, the applicants commenced judicial review proceedings. Initially, they sought:

• injunctive relief restraining Clúid from recovering possession;
• orders quashing Clúid’s decision and its assessment that ZG had no housing need;
• a declaration that s. 39 RTA 2004 is unconstitutional; and
• a declaration of incompatibility with the European Convention on Human Rights.

Over time, the case narrowed. By the time it reached the Supreme Court:

• the claim against Clúid had fallen away;
• the ECHR argument was no longer pursued; and
• the sole live issue was a facial challenge to the constitutionality of s. 39(3)(a) RTA 2004, on the basis that it is underinclusive and in breach of the Constitution.

IHREC appeared as amicus curiae, supporting the challenge but on a different doctrinal basis from that advanced by the applicants themselves.

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3. Legal Issues Before the Supreme Court

The principal issues were:

1. Form of proceedings: Is judicial review an appropriate vehicle for a direct challenge to the validity of primary legislation, or should such challenges normally be brought by plenary summons?
2. Marital status discrimination: Does s. 39(3)(a) indirectly discriminate against children of single parents, in breach of Article 40.1, by effectively allowing children in two‑parent households to remain in the dwelling (through a surviving adult successor) but not children of single parents?
3. Age discrimination: Does the exclusion of children under 18 from the succession class amount to unconstitutional discrimination on the ground of age under Article 40.1?
   • Is age, or the minority/adulthood boundary, a “suspect” classification requiring close scrutiny?
   • What standard of review applies under Article 40.1 — strict scrutiny/proportionality or rationality?
   • Is the 18‑year cut‑off rationally connected to the legislative purpose?
4. Children’s rights: Does Article 42A.1, when read with Article 40.1, require that housing legislation such as s. 39(3) provide for tenancy succession by children under 18, or at least protect their interests differently?
5. Inviolability of the dwelling: Does Article 40.5 render unconstitutional a statutory regime by which the landlord may recover possession following the tenant’s death, where no statutory successor exists?
6. Underinclusive legislation and remedies: If s. 39(3)(a) is deficient because it is underinclusive, what is the appropriate constitutional remedy — striking down, “reading in”, or some form of suspended declaration?

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4. Summary of the Judgment

Chief Justice O’Donnell, for the Court, dismissed the appeal and upheld the constitutionality of s. 39(3)(a) RTA 2004. The key holdings can be summarised as follows:

• Judicial review is not the appropriate form for a direct, stand‑alone challenge to primary legislation. In future, such challenges should ordinarily be brought by plenary proceedings, though the Court did not dismiss this appeal for that reason given its history and the practicalities.
• No marital status discrimination: Section 39(3)(a) does not discriminate on the basis of parental marital status. All children under 18 are equally unable to succeed to a Part 4 tenancy; any difference in outcome stems from the presence or absence of an entitled adult successor (regardless of marital status).
• Age not a “suspect” ground in this context: For age-based distinctions, and in particular the distinction between minors and adults, the appropriate test under Article 40.1 is a rationality test, not strict scrutiny or proportionality. Age-based differentiation of this kind is common, recognised in the Constitution itself, and in anti-discrimination statutes.
• Rationality of excluding under‑18s: Limiting statutory succession to adults is rationally related to the purpose of the RTA 2004, namely balancing security of tenure for tenants (and some close adult occupants) with landlords’ property rights. It is neither arbitrary, capricious, nor the product of prejudice or stereotyping, and thus does not infringe Article 40.1.
• Article 42A does not require a right of child succession: Article 42A.1 reaffirms the natural and imprescriptible rights of the child, particularly in the family and care context, but does not create a constitutional right for a child to remain in a particular dwelling contrary to the landlord’s property rights, nor does it oblige the Oireachtas to design housing legislation by reference to a “best interests” test at the general, legislative level.
• Article 40.5 has limited reach here: The inviolability of the dwelling, properly understood (following Meath CC v Murray), is primarily a protection against unlawful or forcible entry. Section 39(3) neither authorises entry nor offends this protection. Indeed, Part 4 of the RTA 2004 represents a major expansion of tenant protections rather than a constitutional deficiency.
• Underinclusive legislation and remedies: Describing a provision as “underinclusive” does not lower the threshold for unconstitutionality. If underinclusiveness truly results in unconstitutional inequality, the normal remedy is invalidation, not judicial expansion or coercive orders to legislate. The Court cautioned strongly against remedies that intrude upon the legislative domain, referencing the exceptional nature of Heneghan v Minister for Housing.
• No breach of the Constitution, appeal dismissed: The age-based limit in s. 39(3)(a) is constitutional; neither Article 40.1 alone, nor that Article read with Articles 42A and 40.5, is infringed.

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5. Analysis of Precedents and Doctrinal Development

5.1 Article 40.1 and the Modern Equality Jurisprudence

Article 40.1 provides:

“All citizens shall, as human persons, be held equal before the law. This shall not be held to mean that the State shall not in its enactments have due regard to differences of capacity, physical and moral, and of social function.”

Historically, Article 40.1 had a “chequered” career. Challenges invoking it were regularly mounted and just as regularly rejected. Successful constitutional challenges tended to rely instead on unenumerated rights under Article 40.3.

The modern, more structured approach to Article 40.1 crystallised in Donnelly v Minister for Social Protection [2022] IESC 31, [2023] 2 IR 415, where O’Malley J articulated key principles (quoted by O’Donnell C.J. at para. 6), including that:

• Article 40.1 protects against discrimination based on arbitrary, capricious or irrational considerations;
• the challenger bears the burden of proof, against the backdrop of the presumption of constitutionality;
• the Court will afford deference to the Oireachtas in social, fiscal and moral policy;
• closer scrutiny is warranted where discrimination touches attributes intrinsic to the human sense of self or groups vulnerable to prejudice/stereotyping; and
• proportionality is not the governing test; instead, the question is whether the classification is legitimate and rationally connected to the legislative purpose.

Crucially, O’Malley J warned that the Court cannot simply include a claimant within a beneficial class because a “more inclusive” policy would be fairer. That warning is central to O’Donnell C.J.’s reasoning here (para. 7, 85–86).

5.2 Murphy, NHV and Other Article 40.1 Cases

O’Donnell C.J. situates this case in the line of modern equality decisions:

• Murphy v Ireland [2014] IESC 19, [2014] 1 IR 198,
• NHV v Minister for Justice [2017] IESC 35, [2018] 1 IR 246, and
• Donnelly,

where the Court moved away from the restrictive reading of “as human persons” in older cases (Quinn’s Supermarket v AG [1972] IR 1, Murtagh Properties v Cleary [1972] IR 330), and towards a more principled, but still deferential, equality review.

5.3 Age as a Ground of Discrimination: Mallon, Fleming, O’Meara, JD and Brophy

The question whether age is a “suspect” ground has been touched upon, but not resolved, in several cases:

• Mallon v Minister for Justice [2024] IESC 20 (Collins J.) clearly stated there is no indication in the Court’s Article 40.1 jurisprudence that age is a suspect ground (para. 29).
• Fleming v Ireland [2013] IESC 19, [2013] 2 IR 417 noted that some classifications (race, religion, gender, nationality) attract close scrutiny because of a history of prejudice, while “classification by reference to age or disability may be suspect or may be easily explained” and “may be easy to justify” (para. 130). O’Donnell C.J. treats this as only a passing reference.
• O’Meara v Minister for Social Protection [2024] IESC 1, [2024] 1 ILRM 437 (O’Donnell J.) described marital status as different from immutable characteristics such as gender, race, ethnicity, or age (para. 19) — again supporting the view that age occupies a distinct, less sensitive category.
• JD v Residential Institutions Redress Committee [2009] IESC 59, [2010] 2 ILRM 181, as explained in Brophy v DPP [2024] IEHC 392, acknowledges that age-based classifications are not inherently invidious; they may be upheld if not arbitrary, irrational or unfair.

The Court also draws on Re Article 26 and the Employment Equality Bill 1996 [1997] 2 IR 321, where age was recognised as a ground of inequality, but nonetheless held to be a permissible basis for certain legislative distinctions. Modern anti-discrimination statutes (Equal Status Act 2000 and Employment Equality Act 1998) treat age differently from other grounds by:

• excluding under‑18s from “age” discrimination in the Equal Status Act (s. 3(3)(a)); and
• limiting the age ground under the Employment Equality Act to those above compulsory school-leaving age and permitting under‑18 recruitment minima.

Were age a suspect ground requiring strict scrutiny, these legislative carve‑outs would themselves be doubtful. Instead, they underscore that age, and especially the minority/adulthood distinction, “falls into a different constitutional category from distinction on grounds such as sex or race” (para. 43).

5.4 Donnelly: Reaffirmation of the Rationality Standard

Returning to Donnelly, O’Donnell C.J. quotes with approval O’Malley J.’s formulation (para. 189):

“The statutory classification must be for a legitimate legislative purpose, and it will not be legitimate if it is arbitrary, capricious or irrational. Further, the classification must be relevant to the legislative purpose, and it will not be relevant if it is incapable of supporting that purpose.”

This is the test he treats as governing in the present appeal. It firmly displaces any suggestion that a proportionality test applies in Article 40.1 challenges, at least outside the most sensitive suspect grounds.

5.5 Article 42A: JB v KB and AZ & Ors

O’Donnell C.J. reads Article 42A in the light of:

• JB v KB [2018] IESC 30; [2019] 1 IR 270, and
• In the Matter of B (a minor) & CFA v Adoption Authority & C and Z [2023] IESC 12 (Hogan J.).

These cases saw Article 42A as recalibrating the balance between parental rights (often protected via Article 41) and children’s own rights, particularly in decisions around care, custody, and adoption.

The Court in AZ & Ors v Minister for Justice and Equality [2024] IESC 35 (Woulfe J., Collins J. concurring) held that Article 42A.1 obliged the Minister to have regard to the rights and interests of a child (especially a child with special needs) when deciding on deportation of a parent. In that context, the child’s best interests were a primary (though not paramount) consideration.

However, O’Donnell C.J. is clear that AZ & Ors concerned executive decision-making about a specific child, not the validity of generally applicable housing legislation. Importing a “best interests” standard into the legislative process would radically expand Article 42A.1 beyond its text and history and would, in practice, invite courts to substitute their view of what is in “children’s best interests” for the considered choices of the Oireachtas (paras. 67–68).

5.6 Article 40.5: Meath CC v Murray and Clare CC v McDonagh

On Article 40.5, the Chief Justice relies principally on:

• Meath County Council v Murray [2017] IESC 25, [2018] 1 IR 189 (McKechnie J.), and
• Clare CC v McDonagh [2022] IESC 2, [2022] 2 IR 122.

Murray is the leading authority. It confirmed that:

• Article 40.5 is not confined to the prevention of forcible entry; any entry not “in accordance with law” is prohibited;
• however, sweeping characterisations of Article 40.5 as a free‑standing, horizontally applicable, self-executing guarantee were viewed with caution — McKechnie J. warned against an “immense reach” not justified by the text or context (para. 119).

Clare CC v McDonagh accepted this approach. It recognised Article 40.5 as a relevant factor in assessing equitable, especially interlocutory, relief where a local authority sought possession against members of a vulnerable group to whom housing duties were owed. But it did not decide that Article 40.5 bars recovery of public housing per se, nor did it expand Article 40.5 into a broad, socio-economic right to secure occupation.

O’Donnell C.J. rejects attempts — associated in part with dicta of Hogan J. in other contexts — to read Article 40.5 as a sweeping barrier to lawful re‑entry or recovery of possession by landlords. Section 39(3) does not authorise entry at all; any eventual re‑entry is pursuant to lawful termination and the owner’s right to possession. To treat that as constitutionally impermissible would effectively constitutionalise large parts of landlord and tenant law and put this Court in charge of housing policy (paras. 70–83).

5.7 Separation of Powers, Remedies and Underinclusiveness: Murphy, Heneghan, and Tussman & tenBroek

On remedies, the Court places heavy emphasis on:

• Murphy v Attorney General [1982] IR 241 (Henchy J.) — once a provision is found repugnant to the Constitution, it is invalid ab initio and cannot normally justify acts or omissions done under it.
• Heneghan v Minister for Housing (No. 2) [2023] IESC 18, [2023] 2 ILRM 97 — an exceptional case where the Court, faced with the Oireachtas’ decades-long failure to implement a referendum mandate on Seanad elections, and the risk that striking down the existing legislation would make it impossible to legislate, suspended the declaration of invalidity.

O’Donnell C.J. is at pains to confine Heneghan to its extraordinary circumstances: the legislation there was part of the constitutional architecture, and an immediate declaration of invalidity would have paralysed the legislative process.

He contrasts this with suggestions (associated with Hogan J.) that the Court could declare a provision underinclusive yet leave it in force while ordering or strongly pressuring the Oireachtas to legislate in a particular way, with implied threats of coercive orders if it did not do so promptly (para. 93). Such an approach, he warns, risks unprecedented conflict between branches of government and is inconsistent with orthodox separation of powers.

To frame the issue of underinclusiveness, O’Donnell C.J. revisits the classic article by Tussman and tenBroek, “The Equal Protection of the Laws” (1949) 37 Calif. L. Rev. 341. That article distinguishes:

• Underinclusive classifications: those that fail to include all persons who are, in principle, similarly situated to the included class; and
• Overinclusive classifications: those that capture some persons who are not, in fact, relevantly situated to the statutory purpose.

Tussman and tenBroek, and O’Donnell C.J. following them, note that underinclusive schemes can often be justified by:

• incrementalism in lawmaking;
• pragmatic limits on legislative reach; and
• the idea that “the law does all that is needed when it does all that it can”.

Therefore, a finding that a statute is underinclusive does not necessarily compel a finding of unconstitutionality. But if underinclusiveness does amount to unconstitutional discrimination, then the normal consequence is invalidation, not judicial re‑drafting. Describing a provision as underinclusive cannot be used strategically by challengers to lower the threshold for constitutional condemnation (paras. 87–93).

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6. The Court’s Legal Reasoning Applied to the Case

6.1 Marital Status Argument Rejected

The applicants’ primary theory was that s. 39(3)(a) indirectly discriminates against children of single parents, by comparison with children of married or cohabiting couples. The suggested comparator was a child of 14–15 in a two‑parent household whose surviving parent could succeed to the tenancy and thereby allow the child to remain in the dwelling.

The Court rejects this for two main reasons:

1. On its face, Section 39(3)(a) is neutral as to marital status. It confers succession rights on:
   • spouses and civil partners;
   • cohabitants (as defined in the 2010 Act) of either sex; and
   • adult children and parents.
   Whether a child can remain in occupation depends on whether any of these adult residents are present and wish to continue the tenancy — not on the marital status of the child’s parents.
2. Differences in outcome are not drawn along marital status lines. The survival of the tenancy could equally depend on:
   • a non-parent cohabitant;
   • a parent of the deceased tenant;
   • an adult sibling (if over 18 and the tenant’s child); or
   • any other qualifying adult class member.
   Thus, children of single parents and children of married parents are treated the same as a matter of law: neither has a right to succeed to the tenancy below age 18; both depend on an adult successor.

Given that the “line” s. 39(3)(a) draws is between adults and minors, not between children of different parental marital statuses, the marital status-based Article 40.1 challenge is inherently misconceived.

6.2 The Age-Based Challenge: Is Age a Suspect Ground and Is the Cut-Off Rational?

(a) IHREC’s argument

IHREC advanced a more direct challenge. It argued that:

• Section 39(3)(a) discriminates directly on the face of the statute by excluding all under‑18s from succession, while including adult children;
• age is, or should be treated as, a suspect ground warranting close scrutiny, especially given children’s vulnerability; and
• even on a rationality test, the exclusion is irrational in light of the vulnerability of children and the centrality of a secure home to their welfare.

IHREC suggested that a constitutionally compliant remedy would be to allow minors themselves to succeed to the tenancy, possibly drawing on the common law allowing minors to enter voidable leases for necessaries.

(b) The Court’s threshold response: Age and the standard of review

O’Donnell C.J. accepts that the statute draws an explicit age-based distinction, but rejects the contention that age (or the minority/adulthood boundary) should be treated like race or gender. His key points:

• Age is in one sense immutable (one cannot change one’s history), but it is also inherently dynamic and not ordinarily the target of deep-rooted social prejudice in the way race or gender can be.
• Differentiations between children and adults are:
  • commonplace in law,
  • explicitly recognised by the Constitution itself (e.g. voting age, eligibility to run for office), and
  • embedded in the law of capacity, contract, and tenancies.
• Anti-discrimination legislation confirms that although age is a ground of discrimination, the minority/adulthood threshold is treated as non‑suspect (e.g. Equal Status Act s. 3(3)(a); Employment Equality Act s. 6(3)).

He therefore applies the rationality test from Donnelly: is the distinction:

• pursuing a legitimate legislative purpose, and
• rationally connected to that purpose, rather than arbitrary, capricious, or founded on prejudice/stereotyping?

(c) Application of the rationality test

The legislative purposes behind Part 4 and s. 39 include:

• promoting security of tenure for tenants of domestic premises (a significant departure from common law, which recognised termination of tenancies at death);
• limiting the impact on landlords’ property rights to a degree considered consistent with the common good; and
• creating a limited, defined class of successors (spouse/partner, parent, or adult child in occupation) who may carry on the tenancy.

In that context, O’Donnell C.J. stresses:

• The law of landlord and tenant assumes that tenants are adults capable of entering binding agreements, paying rent, and assuming obligations for potentially indefinite periods.
• Children’s occupation of a dwelling is ordinarily derivative, dependent on the position of their parents or guardians. They do not generally decide where they live or have legal autonomy to insist on remaining in particular premises.
• Extending a statutory right of succession to all minors would be a significant additional encroachment on landlords’ property rights, especially in the private sector and social housing sectors alike.

He finds it rational for the Oireachtas to:

• limit succession to adults, and
• treat minors as occupants whose position is indirectly protected through adult successors.

While acknowledging the sympathetic facts and the intuitive “fairness” of allowing EW to remain in the Clúid flat, O’Donnell C.J. emphasises (following Donnelly) that the Constitution does not require the most inclusive or generous possible scheme, nor does it empower the Court to rewrite legislation because a wider scheme would be “fairer”.

(d) Common law on minors’ leases

IHREC invoked the common law on minors’ contracts, including leases, as summarised by the Law Reform Commission and Clarke’s Contract Law in Ireland. At common law:

• a minor could take a lease (especially if for “necessaries”), but
• the lease was voidable at the minor’s option, to be affirmed or repudiated within a reasonable time after reaching majority.

O’Donnell C.J. considers this unhelpful to the constitutional argument:

• It actually demonstrates that minors are treated differently from adults; they have a special capacity regime.
• It addresses voluntary contracts between parties — the landlord chooses to contract with a particular minor, accepting the risk of repudiation.
• By contrast, s. 39(3)(a) is a mandatory statutory regime requiring all landlords to accept any qualifying statutory successor. Extending this to minors would be a qualitatively different intrusion on property rights.

Given these factors, the age-based exclusion of under‑18s from succession is held to be rationally related to the purposes of the tenancy regime and not constitutionally infirm.

6.3 Article 42A and Children’s Rights

The applicants and some judges in separate opinions argued that Article 42A.1 strengthens the case against s. 39(3)(a), by committing the State to:

“as far as practicable, by its laws protect and vindicate [the natural and imprescriptible rights] of all children”.

O’Donnell C.J. accepts:

• Article 42A.1 affirms children’s distinct constitutional status and their possession of natural and imprescriptible rights; and
• It was intended, at least in part, to recalibrate the balance between parents’ rights (Article 41) and children’s rights, especially in care and family law contexts.

But he draws a firm line:

• There is no recognised natural or imprescriptible right of a child (or adult) to live in a particular dwelling contrary to the landlord’s wishes.
• Article 42A.1 is not a general mandate requiring the Oireachtas, in every social or economic statute affecting children, to adopt whatever policy a court would view as best for children.
• Cases like AZ & Ors concern administrative decisions about specific children; importing a “best interests” standard at the legislative level would fundamentally alter the constitutional balance and potentially transform the courts into general arbiters of social policy.

He also notes:

• no evidence was adduced that EW would be rendered homeless or uncared for if he could not remain in the Clúid flat; and
• EW’s own voice has not been heard in the litigation, weakening any claim to speak of his particular rights and interests.

For these reasons, Article 42A does not tip the balance against the constitutionality of s. 39(3)(a). If anything, it confirms the legitimacy of treating children differently from adults in some contexts, given their distinct needs and capacities.

6.4 Article 40.5 and the Inviolability of the Dwelling

Article 40.5 states:

“The dwelling of every citizen is inviolable and shall not be forcibly entered save in accordance with law.”

Some High Court dicta had pressed for a broad reading of “inviolable” as implying extensive protections for occupation, including in civil disputes between private parties. Hogan J., in his separate judgment in this case, explored the Weimar and French constitutional antecedents and suggested a stringent interpretation of inviolability, possibly reflecting historical memories of eviction.

O’Donnell C.J. declines to follow this approach and instead:

• reaffirms Meath CC v Murray as the authoritative statement of Article 40.5’s meaning;
• notes that the focus on forcible entry by the State was central to the drafters’ intention;
• rejects the idea that “inviolable” can be read so broadly as to render the explicit reference to “forcible entry” redundant; and
• highlights that lawful entry (including re‑entry by a landlord entitled to possession) is explicitly contemplated by the phrase “save in accordance with law”.

He emphasises:

• Section 39(3) does not itself authorise any entry; it merely sets conditions under which a tenancy is deemed to continue after the tenant’s death.
• Where the statutory conditions are not met, the tenancy terminates (mirroring common law), and the landlord, as the person entitled to possession, may recover the premises through lawful procedures.
• It would be an inversion of logic to treat a statute that enhances tenants’ security of tenure and introduces a novel succession right as constitutionally defective because it does not go even further.

Article 40.5 therefore provides no basis for invalidating s. 39(3)(a).

6.5 Procedural Point: Plenary Proceedings vs Judicial Review

A significant, forward‑looking aspect of the judgment is the Court’s guidance on the proper form of proceedings.

Building on observations in Donnelly, O’Donnell C.J. states that:

• Where a case consists of a direct challenge to the validity of primary legislation (entitled to the presumption of constitutionality), it should ordinarily be brought by plenary summons, not by judicial review.
• Plenary proceedings allow:
  • oral evidence;
  • discovery and interrogatories;
  • a more complete exploration of facts and context; and
  • a better evidential basis for courts before striking down or upholding legislation.
• Judicial review remains appropriate where:
  • the primary target is an administrative decision; and
  • a constitutional challenge to the underpinning statute is incidental.

He does not dismiss the appeal on this ground because:

• the case began as a legitimate judicial review against Clúid’s decision in an urgent context; and
• the State accepted that the High Court had adjudicated substantively on the constitutional issue and leave to appeal was granted.

However, for future cases, his message is plain: direct constitutional challenges to Acts of the Oireachtas should be litigated by plenary action.

6.6 Practical and Policy Considerations

O’Donnell C.J. ends with a reflection on the practical consequences of the litigation:

• Because of the proceedings and undertakings, the Clúid apartment has remained largely unoccupied for over three years.
• During a period of acute housing need, especially for social housing, this unit has not been available to any person on the housing list.
• Even if the applicants had succeeded, there is no guarantee they would have benefited: the Oireachtas might have responded by narrowing or abolishing succession rights, or by drawing alternative boundaries that did not suit EW’s situation.

This, he suggests, illustrates the pitfalls of expansive, under-specified constitutional litigation, and underscores the importance of:

• clear, well‑focused claims;
• robust evidential foundations; and
• awareness of the separation of powers and institutional capacities.

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7. Impact and Implications

7.1 Equality Law and Age-Based Classifications

The judgment firmly establishes that:

• Age — in particular the minority/adulthood threshold — is not a “suspect” classification akin to race or gender;
• Article 40.1 challenges to age-based distinctions will generally be assessed under a rationality standard, not proportionality or strict scrutiny;
• Legislative distinctions that treat minors differently from adults will be upheld where:
  • they pursue a legitimate purpose; and
  • the adult/minor distinction is rationally connected to that purpose.

This has clear implications for:

• eligibility rules in social welfare, education, and taxation that turn on age;
• capacity-related rules (e.g. appointment powers, contractual capacity, voting, eligibility for office); and
• housing and tenancy rules which reserve certain rights to adults.

It does not mean age can never be the basis of unconstitutional inequality, but it sets a high threshold: challengers must show arbitrariness, caprice, or irrationality, or that the distinction is infected by prejudice or stereotyping.

7.2 Tenancy Law and Social Housing Policy

On the substantive housing issue, the Court:

• confirms the constitutionality of limiting statutory succession rights to tightly defined categories of close adult relatives in occupation; and
• reaffirms that the RTA 2004 represents a major extension of tenants’ rights beyond both common law and earlier landlord and tenant statutes, rather than a constitutional baseline that the Oireachtas must continually expand.

For approved housing bodies and private landlords alike, the decision:

• provides certainty that they are not constitutionally obliged to accept minors as statutory tenants or to permit succession by relatives outside the statutory class;
• supports the legitimacy of policies (like Clúid’s) that condition succession to social housing tenancies on:
  • demonstrated housing need;
  • local authority nomination; and
  • certain residency or relationship criteria.

At the same time, the judgment leaves the Oireachtas free, as a matter of policy, to design more flexible or child‑sensitive succession regimes if it chooses. It simply holds that the Constitution does not require it.

7.3 Article 42A and Children’s Rights in Non-Family Contexts

The decision draws a sharp distinction between:

• Article 42A’s role in family and care contexts (custody, adoption, care orders, deportation decisions affecting family life); and
• its limited bearing on general social and economic regulation (such as tenancy legislation).

This will likely influence future arguments seeking to deploy Article 42A to challenge:

• general housing allocation rules;
• school admission policies;
• child-related social welfare schemes; and
• any legislation that affects children’s living environments in a broad way.

Such arguments will face a demanding threshold: they must demonstrate a clear connection between the impugned law and an interference with the natural and imprescriptible rights of children, and not merely a policy disagreement.

7.4 Article 40.5 and Housing Security Litigation

The judgment limits the reach of Article 40.5 in landlord–tenant disputes:

• Article 40.5 remains a strong shield against unlawful or forcible entry by the State and perhaps by private actors empowered by law.
• But it is not a general weapon to nullify lawful mechanisms for recovering possession on expiry, breach, or termination of tenancies — whether private, commercial or social.

This will temper attempts to convert Article 40.5 into a de facto constitutional right to secure housing.

7.5 Procedural Practice in Constitutional Litigation

Perhaps the most concrete practical legacy of the case is the Court’s insistence that:

• Direct constitutional challenges to primary legislation should normally be brought by plenary summons, not by judicial review.
• Judicial review remains appropriate where the constitutional issue is ancillary to a challenge against an administrative decision.
• Courts may, in case management, convert judicial review proceedings into plenary actions where the constitutional issue looms large and factual exploration is necessary.

This guidance will affect how practitioners frame and issue constitutional challenges, and may reduce the tendency to seek swift but potentially evidentially thin determinations via judicial review.

7.6 Remedies and Judicial Restraint

The Court’s discussion of underinclusiveness and remedies signals a broader stance of institutional modesty:

• Courts must be cautious about remedies that amount to judicial legislation, such as reading additional categories into a statute.
• Threats of coercive orders compelling the Oireachtas to legislate are viewed as incompatible with the separation of powers, save perhaps in the most exceptional cases akin to Heneghan.
• Often, where unconstitutionality rests solely on underinclusion, the appropriate course may be either:
  • to strike down the provision (leaving policy response to the Oireachtas); or
  • to conclude that the underinclusion is constitutionally tolerable in light of legislative discretion and incrementalism.

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8. Complex Concepts Simplified

8.1 Presumption of Constitutionality

When a law passed by the Oireachtas is challenged, the Court starts from the assumption that it is constitutional. The challenger must produce convincing legal and factual arguments to displace that presumption. Doubts are resolved in favour of validity.

8.2 Article 40.1’s Rationality Test v Proportionality

• Rationality test: As applied here, the court asks:
  • Is the classification (e.g. adult v minor) serving a legitimate purpose? and
  • Is it reasonably connected to that purpose, rather than arbitrary or based on prejudice?
  The legislature is given considerable room to draw lines, even if the lines might be rough at the margins.
• Proportionality: A stricter test often used for restrictions on fundamental rights. The court asks whether:
  • the aim is sufficiently important;
  • the measure is rationally connected to the aim;
  • a less restrictive measure could achieve the same objective; and
  • the benefits outweigh the harm.
  This is not the standard the Court applies under Article 40.1 in this context.

8.3 “Suspect” Classifications

In some constitutional systems, certain grounds (like race or religion) are “suspect” because:

• they relate to characteristics central to identity; and
• they have a history of prejudice and stereotyping.

Laws that classify people on such grounds are subject to exceptionally intense scrutiny. The Irish Supreme Court, however, has deliberately avoided rigid categories of suspect classifications. It prefers a more flexible approach focused on the nature of the characteristic and the risk of prejudice, rather than fixed tiers of scrutiny. In this case, age (especially minority/adulthood) is held not to fall into that “suspect” category.

8.4 Underinclusive and Overinclusive Legislation

• Underinclusive: A law that confers a benefit on some people in a relevant category but omits others who are in principle similarly situated.
  Example: a tax credit only for widowers, not widows.
• Overinclusive: A law that imposes a burden or denies a benefit to a class that includes people who should not be included.
  Example: banning all people under 30 from holding driving licences, regardless of driving record.

Underinclusive laws are not automatically unconstitutional. Legislatures may proceed piecemeal, or start with a narrower class and expand later. The question under Article 40.1 is whether the inclusion/exclusion line is arbitrary or irrational.

8.5 Horizontal and Vertical Effect

• Vertical effect: Constitutional rights usually operate between the State and individuals. A statute or administrative act that infringes rights can be struck down.
• Horizontal effect: When constitutional guarantees are applied directly between private parties (e.g. between landlord and tenant, or employer and employee). Article 40.5’s horizontal reach is debated; this judgment signals caution about treating it as a broad, self-executing constraint on private relationships.

8.6 Plenary Proceedings vs Judicial Review

• Judicial review: A streamlined procedure (by way of application for leave and then substantive hearing, usually on affidavit) to challenge administrative decisions, often on public law grounds.
• Plenary proceedings: Full civil proceedings begun by plenary summons, allowing for:
  • oral evidence;
  • cross-examination;
  • discovery;
  • interrogatories; and
  • more detailed factual inquiry.

The Court here advises that where the main issue is whether an Act of the Oireachtas is unconstitutional on its face, a plenary action is generally the appropriate route.

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9. Conclusion: Significance in the Broader Legal Context

This judgment in ZG & EW v Ireland & Attorney General is significant on multiple levels.

First, it clarifies that age-based distinctions, particularly between minors and adults, are constitutionally permissible under Article 40.1 when they are rationally connected to a legitimate legislative objective. The Court resists any move to treat age as a suspect ground demanding strict scrutiny, and reaffirms a deferential but meaningful rationality standard under Donnelly.

Second, it places clear limits on the expansionist readings of Article 42A and Article 40.5. Children’s rights and the inviolability of the dwelling remain vital constitutional commitments, but they do not morph into a general constitutional right to remain in a particular dwelling or into judicial control over the design of tenancy legislation. In particular, the case underscores that property rights and general housing policy remain primarily matters for the Oireachtas, subject only to review for irrational or prejudicial classifications.

Third, the decision advances the law of procedure in constitutional litigation by strongly encouraging the use of plenary proceedings for direct statutory challenges. This serves both the integrity of the judicial process (by ensuring better evidence) and the integrity of the Constitution (by avoiding hasty or under‑informed invalidations of legislation).

Fourth, the discussion of underinclusive legislation and remedies stresses the Court’s commitment to the separation of powers. The judiciary will continue to police constitutional boundaries but will do so with caution, particularly in areas of complex social and economic policy like housing. Courts will avoid remedies that effectively rewrite statutes or coerce the Oireachtas into legislating in particular terms, reserving exceptional remedial devices (like those in Heneghan) for truly exceptional constitutional breakdowns.

Finally, the judgment is a sober reminder that constitutional guarantees of equality do not equate to a general fairness jurisdiction. The Court expresses sympathy for EW’s difficult situation but insists that the Constitution’s role is to prevent arbitrary or prejudicial classification, not to guarantee the “fairest” or most desirable outcome in every hard case. The legislature retains wide space to design, refine, or reform tenancy succession rules — including rules more sensitive to the needs of children — but is not constitutionally compelled to adopt any particular model.

In sum, ZG & EW consolidates the modern approach to Article 40.1, cabins the ambit of Articles 42A and 40.5 in housing law, and sets important procedural and remedial markers for future constitutional litigation in Ireland.