Breyer v. Germany, No. 50001/12, ECtHR (Fifth Section), 30 January 2020

Respect for private life. Legal obligation on service providers to store personal data of users of pre-paid mobile-telephone SIM-cards and make them available to authorities upon request. Storage proportionate to legitimate aims of protecting national security.

Art. 8 ECHR
Art. 10 ECHR

The Court has acknowledged that, when balancing the interest of the respondent State in protecting its national security through secret surveillance measures against the seriousness of the interference with an applicant’s right to respect for his private life, the national authorities enjoy a certain margin of appreciation in choosing the means for achieving the legitimate aim of protecting national security. The breadth of the margin of appreciation varies and depends on a number of factors, including the nature of the Convention right in issue, its importance for the individual, the nature of the interference and the object pursued by the interference. The margin will tend to be narrower where the right at stake is crucial to the individual’s effective enjoyment of intimate or key rights. Where, however, there is no consensus within the member States of the Council of Europe, either as to the relative importance of the interest at stake or as to how best to protect it, the margin will be wider.