On the 2nd March, the Court of Justice of the European Union released a statement about the judgement H.K. v Prokuratuur, which stated that the access, for purposes in the criminal field, to a set of traffic or location data in respect of electronic communications, allowing precise conclusions to be drawn concerning a person’s private life, is permitted only in order to combat serious crime or prevent serious threats to public security.
Here is the link to press release.