Zernikow on Conflict of Law Rules for Employment Contracts as Means to Achieve EU Integration

Marcel Zernikow (University of Pau and Pays de l’Adour) has kindly prepared this presentation of his recent book titled Les règles de conflit de lois confrontées au marché intérieur. Étude en droit international privé européen du travail (Conflict of Law Rules Confronted with the Internal Market. A Study of the European Private International Law of Employment) published by L’Harmattan in 2024. 

What has become more evident over the past years has always existed in isolated cases. The international character of the work relation adds a supplementary complexity to employment law litigation. Let us only mention the examples of transnational teleworkers, crew members, mobile workers or posted workers to illustrate common legal issues. Starting from the relevance of Private International Law (PIL) of Employment in an integrated market, the monograph deals with the specific conflict of law rules of the European Union (EU). Its title also refers to the possible confrontation between the solutions given to the conflict of law and the law of the internal market of the EU. Thus, alongside other studies on European PIL, this research has chosen its field of analysis for reasons of coherence between PIL and the legal order into which the relevant rules for worker mobility are enshrined. From this point of view, this book will also serve as a starting point for reflecting on regionalism and PIL.

Precisely, our study, which is an updated version of a dissertation defended at the University Paris I Panthéon-Sorbonne in 2019, searches to establish the appropriate mechanisms in PIL of employment for the integration of the internal market as a legal concept. To respond to this problematic, it is necessary to read the conflict of law rules in the light of the substantive law of the EU in a broad sense. In other words, PIL should be understood as a means to achieve the integration of the EU.

The thesis proceeds in a binary dialectic which, in the first part, establishes a link between conflict of law rules and EU law. We know that the relevant conflict of law rules in our (European) jurisdictions are those adopted by the EU. For understanding and interpreting them, one must, first, remind oneself of their foundations. What has first arisen in the form of international conventions has then been adopted as proper EU legal acts relying on the competence of the treaty (article 81, § 2 TFEU). The latter refers expressly to the link between PIL and the proper functioning of the internal market. Even if the existing EU PIL rules should nowadays have integrated the requirements of EU law, our purpose is to underline that the confrontation between the solutions of the conflict of law mechanisms with internal market law still takes place, more particularly, when (national) unilateral overriding mandatory rules (lois de police) are at stake. Paradoxically, the latter are promoted by the EU instruments in PIL, such as the Posted Workers Directive (and its last amended version). In this sense, they are an indicator for a missing harmonisation of the multilateral conflict of law rules for this subject matter. Namely, article 8 of the Rome I Regulation is imprecise when it comes to determining the connecting factor for posted workers and is – only insufficiently – supplemented by the Posted Workers Directive. In other contexts, unilateral rules can also be identified, as a mechanism to compensate the missing harmonisation of private law in the branch of labour law, where a strong divergence (e.g. the scope of collective labour law or even the scope of labour law as such) is observed. In general, from the perspective of the freedoms of movement, unilateral rules are put under scrutiny because they promote the territoriality of the conflict of law reasoning.

Positively, while considering the foundations of the EU conflict of law rules, our aim is to identify the principles that the European conflict of law rules should reflect. The law of the internal market, initially understood, in our context, as referring to the free movement of workers and services, has over the past 25 years, been completed by the law of the area of freedom, security and justice whose provisions are nowadays the seat of the EU’s competence for adopting PIL rules. Moreover, the Charter of fundamental rights interacts with the conflict of law rules. Gradually, the analysis of the evolution of EU law should bring us to the identification of what characterises the concept of the internal market and influences the EU’s competence for adopting conflict of law rules.

The second part of the study has the objective to apprehend the European conflict of law mechanisms in a concrete manner. To conclude on how EU law characterises the conflict of law rules, one must draw some lessons from the concept of the internal market with respect to the mobility of workers. The internal market has evolved as an area of free movement for workers. This also brings up the serious question of its articulation with other freedoms such as those of services and of establishment. Eventually, their articulation leads us to the definition of the worker protection principle which is enshrined in the internal market and to which the relevant PIL regulations refer by mentioning the protection principle. In other words, EU law is both substantive law in the sense that it harmonises the national legislations and PIL in the sense that it regulates the applicable law. Both share common principles such as the worker protection principle.

From a theoretical point of view, this conclusion has further implications on the function of the European conflict of law rule which is regulatory insofar as it also contributes to the proper functioning of the internal market. More precisely, it is limited to regulating the internal market internally. Concerning the function of the conflict of law rule in legal relationships implying a third State, it has been noted that the conflict of law rule would have a more distributive function, as it would decide on the application of an EU vs. a non-EU substantive legislation.

As part of a mass of European PIL acts (contractual and non-contractual obligations, maintenance obligations, divorce, legal partnerships, successions, etc.), the specific conflict of law rules in employment matters are the object chosen for our study on the characteristics of EU PIL. From this perspective, the book necessarily develops the different characteristics and possible evolutions of the European conflict of law rules that may have relevance beyond the field of employment law. The reference to more general considerations such as that on harmony of decisions implying itself legal certainty and predictability is inevitable. However, the focus is the substantive orientation of the specific conflict of law rule in employment matters.

The EU conflict of law rule responds to the characteristics of a result-oriented conflict of law rule. Our book suggests witnessing the process of matérialisation of the conflict of law rule through a case study that analyses the absorption of the substantive rationale formerly expressed in the unilateral conflict rules by result-oriented rules. Technically speaking, the European conflict of law rule uses multilateral and alternative connecting factors. These are mostly – but not exclusively – contained in article 8 of the Rome I Regulation. One must note beforehand, that in the specific context of employment matters, the presence of freedom of choice raises serious doubts for the national judges who seem to radically restrict the choice of law. As a result of the influence of the principle of proximity in an interplay with the worker protection principle, the habitual workplace evolves as the principal connecting factor whereas the closest connection remains a possible connecting factor. The place of business through which the worker was engaged should be limited to specific cases. Eventually, against the background of the substantive harmonisation of labour law at the EU level, this study also insists on the need of autonomous notions for this context (e.g. who is a worker?).

In conclusion, this panorama distinguishes the arising European conflict of law rules, while we have learnt from Gamillscheg’s Course that the former (national) conflict of law mechanisms of European countries were different. One should repeat that what is identified here are the proper EU conflict of law mechanisms which follow the rationale of EU law. Thus, our analysis is proper to this context, and we would come to slightly different results if we took the PIL in another (e.g. regional or global) context.