Introduction
Human rights are not merely moral, political or legal – they combine aspects of all three. Human rights law mostly recognises such rights vis-à-vis the modern state in the international legal instruments and the national constitutions, which may be called as “the default verticality” (Bhatia, 2023). During the period of Enlightenment to which it owes its existence, human rights were exclusively applied to the relationships governed by public law; however, today they have moved beyond this framework, and are also applied to private law relationships. Jurists who want to understand the role of the human rights in private law mostly prefer to clarify the relationship between them under the umbrella of the notion of the ‘horizontal effect of human rights on private disputes’. Until recently, this was also my approach to the topic. Even though I had my doubts about the notion, I tried for a long time to explain human rights in private law on this borderline, as most people have done (Colombi Ciacchi, 2006; “Procedural Effect” inspired by Canaris See Mak, 2008, 56; Canaris, 1999, 35, 91). It can, however, be said that there is no compelling reason to carry on using the notion of horizontal effect. In the following, I will argue that we should no longer try to conceptualise human rights in private law as direct or indirect horizontal effect, but should discuss their ex officio application to private law.
Firstly, proponents of the doctrine of indirect effect have generously inclined to accept that the theoretical contrast between indirect and direct effect is melting away like ice in a cocktail before the court (Collins, 2017, 233; Kumm, 2006). When the sources of a claim-based right are constitutional rights, there is the direct effect of human rights on private disputes, and constitutional rights affect private conduct in general. When it comes to the moment of interpretation and application of private law together with constitutional rights, it would be conceptualised as augmented or strong indirect effect in the best scenario ( see Collins, 2014; Direct effect/unmittelbare Drittwirkung Nipperdey, 1961; Constitutional rights are conceived just as “values” for indirect effect. Indirect effect/mittelbare Drittwirkung Dürig, 1984, 215-246; Indirect effect together with protective functions of the state see Canaris, 1999, 35, 91). I don’t have enough space to discuss the classification. Alexy classified as three of them and ended up with outcome-neutral (Alexy, 2009, 358-365). As the adjectives used not only strong or weak but also direct or indirect effect are not illustrative terms how to affect private disputes exactly, the distinction of the doctrine of horizontal effect results in literal interpretation of law like static and frozen photograph before the court regardless of transformative role of private law.
Secondly, the deconstruction thesis or the sceptical strand against human rights law has already been refuted by a large number of established principles of human rights law such as the margin of appreciation, the principles of subsidiarity and the proportionality. (For the sceptical strand see Collins, 2014; Cherednychenko, 2007; Mak classifies human rights approaches as the legal-political stakes in private law. The first approach is a sceptical strand, the second one is social justice, the third one is citizenship perspective through European Private Law (Mak, 2025, 98). As human rights have dual function consisting of both rights against state and as protection, rising wave of the development of human rights law has been in favour of the procedural review for the past decade (Spano, 2018; Gerrards-Brems, 2018; Huijbers, 2021). The EC(t)HR implements the procedural review both as a judicial interpretive technique and as a tool of shared responsibility, related to the interrelationship between the Court and national authorities. It can therefore be said that there is no logical or legal reason to claim that human rights law is either an invasive or destructive discipline on private law, otherwise human rights law would lose its dual function (Compare Nolan, Robertson, 2011). After a brief discussion of Turkish case law, I will argue that human rights are applied ex officio to private disputes.
Turkish Case Law
The answer of who is bound by human rights can be accepted as all persons under some constitutions that have exceptionally regulated by the constituent power. (Like Section 8 (2) of the South African Constitution see Zitzke, 2015; Bambrick, 2025). One of the unique examples is that the Article of 11 of the Turkish Constitution has been laid down that “The provisions of the Constitution are fundamental legal rules binding upon legislative, executive and judicial organs, and administrative authorities and other institutions and individuals.” In addition to private law, the Article 152 and the Article 90 (5) could be evaluated as the sources of human rights in private law. While a judge hearing a case shall be duty bound to review the law or the decree constitutionally to be able to apply to the Turkish Constitutional Court under the Article 152, in the case of a conflict between international human rights treaties and national law, international human rights treaties shall prevail over the law under the Article 90 (5).
After the rejection of the claim that the provision is contrary to the Constitution under the concrete constitutional review in 2011, the TCC held in an individual application that there had been a violation of protection of the material and spiritual existence of the person, which is the groundbreaking case named Sevim Akat Eşki, related to the surname of married women in 2013. (See also Gülsim Genç, B. No: 2013/4439, 6/3/2014, §39; Neşe Aslanbay Akbıyık, B. No: 2014/5836, 16/4/2015, §44.) According to the TCC, when there is a conflict between the European Convention or other human rights treaties and national law, it is obligatory to apply the human rights treaties to a legal dispute in accordance with the Article 90 (5). This is an “implicit derogatory rule” to facilitate the ordinary courts to ignore a rule of private law that conflicts with human rights treaties without revoking it, which provides contra legem interpretation for the national judges. It could be said that the Article 90 (5) of the Constitution as an implicit derogatory rule paves the way for the human rights review by the ordinary courts in addition to the process of the concrete constitutional review. (Unbinding and interpretative judicial review conceptualises as weak judicial review. See Tushnet, 2007; Gardbaum, 2013, 13; In Turkish literature see Acar, 2017; Gemalmaz claims that the substantive dimension of fundamental rights can turn into the applicable law in a case Gemalmaz, 2022, 57-75).
In 2020, the TCC held that the general principles such as good faith, the prohibition of abuse of a right, and the discretionary power to the judge should be seen as a requirement of effective legal protection, which allows for the interpretation in accordance with the Constitution. Therefore, the judge shall interpret the law in accordance with the Constitution in all cases, whether they are disputes between private individuals or disputes in which one of the parties is the public power, and to observe the protection of fundamental rights. (Mehmet Apaydın, B. No: 2015/13099, 8/1/2020, §47.) When it comes to 2022, the TCC concluded a violation of the right to property related to the norm of absolute ban on claims suffered damages and loss caused by mining activities. (Hulusi Yılmaz [GK], B. No: 2017/17428, 1/12/2022, §52, 54, 67). According to the TCC, in cases where the norm is so clear and certain that it does not even allow for interpretation and application in accordance with the Constitution, it is not possible for the Courts not to apply the norm in question spontaneously unlike the Article 90 (5). According to the TCC, in principle, the judges shall apply for concrete constitutional review at first. However, the Court of Cassation have begun to decide the cases of joint custody in relation to the best interests of the child under the Article 90 (5). (Hilal Erdaş [1.B.], B. No: 2018/27658, 6/10/2021, § 46; Yargıtay 2. HD, 4/12/2017, E.2016/18474, K.2017/13800). I do believe that there are no constitutional grounds for further retreat from human rights review before the ordinary courts under the Article 90 (5) for implementation of human rights law in an appropriate way.
In the latest judgment given by TCC, the failure to compensate excessive collateral damage due to high inflation rates had been a violation of right to an effective remedy in connection with right to property (Caner Şafak [GK], B. No: 2024/41763, 8/7/2025, § 56). The important matter is that the state is obliged to take measures to ensure a fair balance between the interests of the parties in private disputes.
Ex Officio Application of Human Rights Before the Ordinary Courts
Ex officio application of human rights to private law is focused on the process of the ordinary courts at first. In my view, if human rights could not be applied ex officio to the private disputes together with the related norm as an absolute duty before the court, the questions remain unanswered as to how human rights violations could be prevented or how conventional private law doctrines could be developed by ordinary courts in accordance with human rights law. (“The Court held that Milieudefensie et al. have invoked the provisions of Articles 2 and 8 ECHR.” See 7.6. ECLI:NL:GHDHA:2024:2100, Judgment of 12 November 2024.) My main arguments could be summarised that it is really difficult to distinguish between direct and indirect effects in the light of the private conduct criterion, and that it is unnecessary to continue the ongoing debates on the distinction of horizontal effect in each jurisdiction. The private conduct would be already affected when human rights are applied ex officio to the related norm before the court. I do believe that it differs from traditional indirect effect. Because human rights are not just values (Compare Michelman, 2022, 190; compare Article 94 of the Dutch Constitution for “no ex officio application” see Hartkamp, 2016, Ch.6). As private law has already sort of open-ended norms to be able to apply human rights to private law, private law has also protective function of human rights beyond open-ended norms.
To be more precise, I would like to stress that private law could be an interference with human rights either as an action or as an omission for legal subjects with dual function, both consisting entirely of the restriction and protection. Answers to the question of how human rights apply to private law can easily be simplified with underlining applicable human rights amongst subjects like balancing between social rights and right to property or between freedom of will and other human rights or between privacy and freedom of expression. Since any kind of justification of private rights to the exclusion of human rights would end up denying the existence of human rights mechanisms, the nature of private rights is strongly correlated with human rights. In this way, the judge can and should apply human rights to private law such as bona fides, unfair terms in contract law, tort law, duty of care by identifying applicable human rights amongst the subjects of human rights.
The main benefit of that contributes to restrict the undefined legal terms and develops the classical doctrines of private law to be able to find appropriate solutions to common issues under the roof of human rights. It can be useful tool for teleological reduction (Canaris, 1995, p.391). The method that I argue brings applicable human rights into private law more before the ordinary courts. The main issue is how to balance rights and interests in the context of individual autonomy beyond literal meaning of norms and how to develop the classical doctrines of private law to be able to find solutions to common issues such as digitalisation, sustainability, economic crisis, housing policies, food security and so on. The ordinary courts almost undertake human rights review in general (Compare Mak, 2020). In doing so, jurists have chance to discover “living law” under the roof of human rights due to the constitutive functions of human rights in a democratic system.
