strategic surveillance measures examined in that decision used content-related
search terms, but were not linked to specific individuals (cf. BVerfGE 100, 313
<384>). By contrast, the strategic surveillance measures at issue in this case mostly
use formal search terms such as telecommunications identifiers, which make it possible to target specific individuals. Thus, strategic telecommunications surveillance
gives rise to interferences that are fundamentally more far-reaching and more closely
resembles targeted telecommunications surveillance.
(6) Compared to the previous legal framework, an aggravating factor is that, to a
certain extent, strategic surveillance now also allows for traffic data to be retained in
its entirety. The analysis of such traffic data – without specific grounds and merely
guided by the purpose pursued – can provide deep insights into the communication
behaviour and movement patterns of the affected persons, which may go far beyond
the content-based analysis of individual communications (cf. regarding the informative value of such data BVerfGE 125, 260 <319>; CJEU, Judgment of 8 April 2014,
Digital Rights Ireland and Seitlinger and Others, C-293/12, C-594/12,
EU:C:2014:238, paras. 48, 56). This, too, considerably increases the weight of interference.
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bb) As specific powers for gathering foreign intelligence, strategic surveillance powers can be justified under constitutional law, despite the particularly serious weight of
interference resulting from such surveillance.
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(1) Yet by refraining from creating specific thresholds for the use of powers, the legislator fails to satisfy a core requirement arising from the rule of law. Such thresholds
are indispensable in general, and are of even greater importance in respect of domestic security authorities, even for less intrusive interferences with fundamental
rights, but certainly for serious interferences such as telecommunications surveillance (cf. BVerfGE 141, 220 <269 et seq. para. 104 et seq.>; 150, 244 <280 et seq.
para. 90 et seq.>). The requirement of thresholds tied to specific circumstances ensures that interferences with fundamental rights are restricted, makes them contingent upon objective requirements and allows for oversight based on independent criteria. An authorisation of such interferences that is solely guided and restricted by the
purpose pursued is generally incompatible with Art. 10(1) GG.
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In principle, this also applies to intelligence services. Insofar as surveillance measures extend to domestic communications, reliable thresholds are required in accordance with the general requirements. The same holds true for surveillance measures
ordered by targeted warrants against specific individuals – whether they are in Germany or abroad –, for instance telecommunications surveillance measures or remote
searches [of information technology systems] (cf. BVerfGE 120, 274 <326 et seq.>;
125, 260 <320 et seq.>; 141, 220 <270 et seq. para. 106 et seq.>; see also § 3 of the
Article 10 Act).
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(2) By contrast, the gathering of foreign intelligence by intelligence services is treated differently insofar as it is aimed at providing general information to the Federal
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