The internet is becoming an increasingly important medium for state authorities - even in an international context - for gaining insights. This work examines how the internet can be utilized by authorities and which fundamental rights of those affected are impacted in the process. This is followed by an analysis of existing constitutional justifications. The focus is on the examination of repressive and preventive covert online searches and the source telecommunications surveillance as a special form. Due to legal and technical difficulties in the standardization and implementation of a constitutionally acceptable covert online search, a call for moderation and caution is ultimately emphasized here.