Telecommunications interception refers to undisclosed monitoring, recording and other processing of a message sent to or transmitted from a network address or terminal end device through a public communications network connected thereto, in order to determinate the content of the message and the identifying data connected to it. Telecommunications interception may be directed only at a message that originates from or is intended for a suspect in a serious offence and the interception is assumed to be very important in the investigation.
The obtaining of base station data refers to obtaining of information on the network address and terminal end device of persons who have logged in to a telecommunications system through a certain base station. A criminal investigation authority may obtain data for the identification of a network address or a terminal end device, if there are grounds to suspect an offence for which the most severe punishment provided is imprisonment for at least one year. Technical surveillance of a device refers to other than solely sensory surveillance, recording or other processing of the operation of a computer or other corresponding technical device or of the data contained therein in order to clarify an offence. They may also install or remove a device, process or program if the performance of the surveillance requires that.