This article explores the – often controversial – role of the CJEU as an interpreter of Directive 93/13/EEC on unfair terms. A fundamental problem that any modern system of private law must address is how to combine two types of provisions: those that are intended to facilitate private ordering through voluntary transactions, and those setting out certain mandatory terms that are intended to protect vulnerable consumers against risks inherent to free market transactions. This article argues that, in response to the failure of various legislative initiatives, the Court’s jurisprudence has acquired both a regulatory dimension and a constitutional dimension. The emergent judicial regime illustrates an important departure from a rule-based conception of private law, based on private autonomy as a stand-alone value, towards an innovative conception that extends proportionality analysis into substantive private law but avoids one-sided outcomes.
Oliver Gerstenberg, Constitutional Reasoning in Private Law: The Role of the CJEU in Adjudicating Unfair Terms in Consumer Contracts. European Law Journal, volume 21, issue 5, pages 599–621, September 2015.