EU Data Privacy Law and Serious Crime: Data Retention and Policymaking offers a comprehensive and comparative study of the right to private life and data retention within the EU and ECHR legal orders. Exploring EU data retention law and the role of Article 8 ECHR in a variety of contexts, from communications data to passenger name record data, the book casts a spotlight on the mainstreaming of the right to private life across EU policymaking, critically analysing the role of the European Commission and the CJEU as guardians of fundamental rights in their rights review of EU data retention measures. The book examines the jurisprudence of the CJEU and ECtHR concerning data retention and State surveillance. Three key developments are identified that threaten the protection and future development of the right to private life within the EU and ECHR legal orders: the converging and diverging standards of the CJEU and ECtHR; the fraught dialogue between the CJEU and national courts; and the rise of the CJEU as the vanguard EU institution for data retention policymaking and supranational judicial scrutiny in Europe. In this dynamic area of EU data protection law and European human rights law, this original and unique book traverses the future development of legal standards within the jurisprudence of the CJEU and ECtHR, giving policy recommendations on how to enhance the right to private life in future EU data retention policymaking. This book will appeal to academics, policymakers, and practitioners interested in the future of the right to privacy in an era of AI and data-driven surveillance.