Dual Criminality is required. A request for ordering and performing the investigative measure shall comprise a copy, a certified copy or a photostat copy of the order of the competent authority. If this is not a court order, the authority requesting judicial assistance shall present a statement explaining that the prerequisites required for such measures are met under the law applicable in the requesting State.
The intervention of foreign agents is subject to authorization by the competent Public Prosecutor`s Office.
Observation measures supported by technical aids or for a period longer than 48 hours or outside of Austrian territory may only be ordered for a period of time that is likely to be required in order to fulfill the purpose, but in any event no longer than for three months. However, the order may be repeated as far as the requirements are persisting.
Observation measures shall be ended when
1. their requirements are no longer fulfilled
2. their purpose has been achieved or can no longer be achieved or
3. the public prosecutor orders the termination of the measures.
The use of technical aids which, by means of the transmission of signals, make it possible to determine the spatial area in which the person under surveillance is located and the opening of vehicles and containers for the purpose of inserting such technical means is permissible in order to support the observation, provided that the observation would otherwise be futile or substantially impeded.
The use of technical aids (also) allowing for the optical and acoustic surveillance is only admissible when the requirements for optical and acoustic surveillance (see measure A.56) are met.
There shall be compliance with a request for judicial assistance which requires a procedure that differs from Austrian laws on criminal procedure, if this is compatible with the criminal procedure and its principles.