Data retention and the future of large-scale surveillance: the evolution and contestation of judicial benchmarks

Recent and upcoming judgments of the Court of Justice of the European Union (CJEU) have resurfaced a much-debated topic on the legal limitations of law enforcement authorities and intelligence services under EU law in implementing surveillance operations. In its decisions, the CJEU has reinstated and at times remoulded its case-law on data retention, unearthing a variety of legal issues. This article aims to critically analyse the legal limitations of (indiscriminate) surveillance measures, the role of the private sector in the scheme, and the line between the competence of the Member States and that of the EU on national security matters. It also aims to remark on the latest developments on the reception of the decisions by the Member States and the EU legislator, as well as on the ongoing dialogue between the CJEU and the European Court of Human Rights (ECHR).