Key paragraph(s) can be found below the document.CASE-OF-BIG-BROTHER-WATCH-AND-OTHERS-v.-THE-UNITED-KINGDOM
307. In its case-law on the interception of communications in criminal investigations, the Court has developed the following minimum requirements that should be set out in law in order to avoid abuses of power: the nature of offences which may give rise to an interception order; a definition of the categories of people liable to have their communications intercepted; a limit on the duration of interception; the procedure to be followed for examining, using and storing the data obtained; the precautions to be taken when communicating the data to other parties; and the circumstances in which intercepted data may or must be erased or destroyed (see Huvig, cited above, § 34; Valenzuela Contreras, cited above, § 46; Weber and Saravia, cited above, § 95; and Association for European Integration and Human Rights and Ekimdzhiev, cited above, § 76). In Roman Zakharov (cited above, § 231) the Court confirmed that the same six minimum requirements also applied in cases where the interception was for reasons of national security; however, in determining whether the impugned legislation was in breach of Article 8, it also had regard to the arrangements for supervising the implementation of secret surveillance measures, any notification mechanisms and the remedies provided for by national law (Roman Zakharov, cited above, § 238)
314. The Court has expressly recognised that the national authorities enjoy a wide margin of appreciation in choosing how best to achieve the legitimate aim of protecting national security (see Weber and Saravia, cited above, § 106). Furthermore, in Weber and Saravia and Liberty and Others the Court accepted that bulk interception regimes did not per se fall outside this margin. Although both of these cases are now more than ten years old, given the reasoning of the Court in those judgments and in view of the current threats facing many Contracting States (including the scourge of global terrorism and other serious crime, such as drug trafficking, human trafficking, the sexual exploitation of children and cybercrime), advancements in technology which have made it easier for terrorists and criminals to evade detection on the Internet, and the unpredictability of the routes via which electronic communications are transmitted, the Court considers that the decision to operate a bulk interception regime in order to identify hitherto unknown threats to national security is one which continues to fall within States’ margin of appreciation.
315. Nevertheless, as indicated previously, it is evident from the Court’s case-law over several decades that all interception regimes (both bulk and targeted) have the potential to be abused, especially where the true breadth of the authorities’ discretion to intercept cannot be discerned from the relevant legislation (see, for example, Roman Zakharov, cited above, and Szabó and Vissy v. Hungary, no. 37138/14, 12 January 2016). Therefore, while States enjoy a wide margin of appreciation in deciding what type of interception regime is necessary to protect national security, the discretion afforded to them in operating an interception regime must necessarily be narrower. In this regard, the Court has identified six minimum requirements that both bulk interception and other interception regimes must satisfy in order to be sufficiently foreseeable to minimise the risk of abuses of power (see paragraph 307 above).