Principle of Proportionality in the Jurisprudence of the European Court of Human Rights in Cases Concerning Workplace Monitoring

This article examines the principle of proportionality in the jurisprudence of the European Court of Human Rights concerning workplace monitoring under Article 8 ECHR. It contrasts two models of proportionality, interest balancing and balancing as reasoning, and show how the Court has increasingly adopted the latter in landmark judgements such as Bărbulescu v. Romania and López Ribalda and Others v. Spain. Particular emphasis is placed on the structural inequality inherent in the employment relationship, which undermines the notion of that relationship as a contract between equal parties and makes contextual, reasoning-based balancing especially relevant in cases concerning labor relations. The analysis highlights how proportionality, to a certain extent, constrains the margin of appreciation and provides normative guidance in adapting national legal frameworks to the challenges of digital surveillance. At the same time, the article cautions against an uncritical drive towards harmonization and eventual unification through instruments such as the GDPR or the AI Act, as excessive standardization may overlook the diversity of national labor markets. It also highlights the risks associated with the expanding role of the ECtHR beyond judicial review. Proportionality, understood as balancing as reasoning, therefore emerges as the suitable model for safeguarding employee privacy and dignity while preserving respect for legal and social pluralism in Europe.