Cross-border observation with the use of technical support is permissable for the investigation of facts and the determination of the whereabouts of the perpetator in an extraditable criminal offence.
The same requirements apply as for the cross-border observation (measure A 70). This means, that in general cross-border observations have to be authorised on the basis of a request for mutual judicial assistance submitted in advance. If the surveillance is supposed to be executed for a longer period than 24 hours or on more than 2 days, the offence at stake has to be of considerable significance and surveillance is permissible only if other means of investigation would offer much less prospect of success or be much more difficult. In cases of particular urgency, in which prior authorisation cannot be requested, cross-border surveillance is permitted only for serious offences listed in Art. 40 para. 7, of the Convention implementing the Schengen Agreement, and has to be notified immediately, during the surveillance to the Federal Criminal Police Office in Wiesbaden. Furthermore, a request for assistance submitted in accordance with Art. 40 para. 1 and outlining the grounds for crossing the border without prior authorisation shall be submitted immediately. This also applies to cases in which it only becomes known later that a border has been crossed. Also in these cases a request must be made immediately after knowledge of the border crossing.