Accordingly, the police normally act in the open, and likewise, their handing of data
predominantly complies with the principle of openness. It is true that to a considerable
degree, the tasks of the police also involve investigations that are initially conducted
covertly against the person concerned. However, this exception applies only to certain information-gathering measures or phases that are supported by specific suspicions, and it does not alter the fact that police work is in principle conducted in the
open. […]
121
The legal order therefore distinguishes between the police, which generally work in
the open, are structured for the fulfilment of operational tasks, and guided by detailed
legal provisions; and the intelligence services, which generally work in secret, are limited to observation and information gathering for political information and consultation, and can thus act within a less complex legal framework. No provision is made for
a secret police.
122
(cc) In light of these differences, provisions that make it possible to transfer data between the police and intelligence services are subject to heightened constitutional requirements. From the fundamental right to informational self-determination follows a
principle of separation of information (informationelles Trennungsprinzip). Under this
principle, data may generally not be exchanged between the intelligence services
and the police. The separation of data may be relaxed only by exception. If exceptions are granted for operational tasks, they constitute a particularly serious interference. Transfers of data between the intelligence services and the police for use in potential operational actions must therefore normally serve a particularly important
public interest which justifies the access to information under the laxer requirements
that apply to the intelligence services. This must be ensured by sufficiently specific
and qualified thresholds for interference based on clearly defined legal provisions;
moreover, the thresholds for the interference with rights in the acquisition of data
must not be circumvented.
123
bb) However, it mitigates the severity of the interference that the counter-terrorism
database is structured as a joint database which is essentially limited to facilitating
access to information, and stipulates that the data may be used for operational tasks
only in urgent and exceptional cases.
124
(1) The challenged provisions design the counter-terrorism database as a set of instruments that – except in emergencies under § 5 sec. 2 and § 6 sec. 2 ATDG – does
not provide information so that the respective authorities can directly perform their
tasks, and especially not their operational purposes, but provides it only as a basis for
further data transfers. It is true that the counter-terrorism database itself enables a
data transfer between the participating authorities by permitting searches of all basic
data, and (as provided in § 5 sec. 1 sentences 1 and 2 ATDG) letting the requesting
authorities have access to the simple basic data under § 3 sec. 1 no. 1a ATDG. However, § 6 sec. 1 sentence 1 ATDG provides that the requesting authority may use
these data only for reviewing whether the data match the person being sought, and
125
25/45