Excerpt from an e-mail of 2007/08/08:
If the German parliament passes the bill on data retention later this year, we will file a complaint with the German Constitutional Court arguing that a blanket retention of the entire population’s communications data is grossly disproportionate and violates the German constitution. The German Constitutional Court has already ruled rather clearly that this is indeed the case.
However, the directive as part of the „aquis commun“ takes precedence even over the German constitution. So the only thing the Court can do is
a. order that the application of the German transposition act be suspended
b. apply for a preliminary ruling (Art. 234 TEC) by the ECJ on whether the DR directive violates human rights as enshrined in European law.
For as long as the directive is in force, the German Constitutional Court is unlikely to declare unconstitutional an act merely transposing European obligations into national law, as such a ruling would entail a major constitutional crisis in the EU.
However, if the ECJ declares the directive void (no matter on which grounds), the German Constitutional Court will be free to declare the German law unconstitutional as this would no longer conflict with European obligations.
By the way: Even if the directive was re-enacted as a framework decision, framework decisions do not have precedence over national constitutional law, according to our Constititional Court (Reason: no co-decision of the European Parliament). So even this scenario would be a major breakthrough. Anyway, a framework decision would require unanimity which did not and is not going to happen.