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BIG BROTHER WATCH AND OTHERS v. THE UNITED KINGDOM JUDGMENT
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).
308. As to the question whether an interference was “necessary in a
democratic society” in pursuit of a legitimate aim, 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
or her private life, the national authorities enjoy a certain margin of
appreciation in choosing the means for achieving the legitimate aim of
protecting national security. However, this margin is subject to European
supervision embracing both legislation and decisions applying it. In view of
the risk that a system of secret surveillance set up to protect national
security may undermine or even destroy democracy under the cloak of
defending it, the Court must be satisfied that there are adequate and
effective guarantees against abuse. The assessment depends on all the
circumstances of the case, such as the nature, scope and duration of the
possible measures, the grounds required for ordering them, the authorities
competent to authorise, carry out and supervise them, and the kind of
remedy provided by the national law. The Court has to determine whether
the procedures for supervising the ordering and implementation of the
restrictive measures are such as to keep the “interference” to what is
“necessary in a democratic society” (see Roman Zakharov, cited above,
§ 232; see also Klass and Others v. Germany, 6 September 1978, §§ 49, 50
and 59, Series A no. 28, Weber and Saravia, cited above, § 106 and
Kennedy, cited above, §§ 153 and 154).
309. Review and supervision of secret surveillance measures may come
into play at three stages: when the surveillance is first ordered, while it is
being carried out, or after it has been terminated. As regards the first two
stages, the very nature and logic of secret surveillance dictate that not only
the surveillance itself but also the accompanying review should be effected
without the individual’s knowledge. Consequently, since the individual will
necessarily be prevented from seeking an effective remedy of his or her own
accord or from taking a direct part in any review proceedings, it is essential
that the procedures established should themselves provide adequate and