Abstract
Mandatory data retention and the use thereof by competent authorities have been the subject of many court decisions in recent years. The joint judgments of the Court of Justice of the EU of 6 October 2020 are the latest in this series.
In these decisions the Court repeatedly declared the prohibition of the general retention of traffic and location data, at the same time defined exceptions to this prohibition and laid down the conditions for their application; these have always to be exceptional and time-limited situations. In the Czech legal system, on the other hand, there is an increasing number of state authorities entitled to request traffic and location data.
The Office for Personal Data Protection has recently been added to them and should now be followed by the Office for the Protection of Competition and the State Hygiene Service. The author has strong doubts as to the compatibility of these proposals with the clear conclusions of the Court of Justice.