In 2006, as a response to hysteria whipped up during the war on terror, the European Union passed the Data Retention Directive. The directive requires member states to log and store all telecommunications and internet data, such as call times, destinations, IP addresses - effectively, full traffic data - for six to 24 months so that police can datamine it (with a court order, of course - but they have tame judges to give them that).
The German Constitutional Court has just ruled Germany's implementation of that directive illegal.
The reason, of course, is privacy. The law requires that the communications details of everyone, regardless of guilt or innocence, be logged and made available to police. While the communications themselves are not recorded and stored, the fact that they were made is - and that violates individual privacy. Who you talk to and when is fundamentally private information, and requires strong evidence of wrongdoing (not to mention relevance) to justify. The law did not require any evidence of wrongdoing at all. As a result, it was a "particularly serious infringement of privacy" and has been struck down.
This means that Germany will be violating the Data Directive. But from the BBC story, it sounds like that will be being "reassessed" later this year. Hopefully Germany and other countries will decide to ditch it entirely.
