Perhaps the largest category of European Union legislation is the directive, which instructs member states to enact legal instruments to meet certain objectives, purposes, and parameters. The principal rationale for this process is the differing legal systems of the member states—drafting directly applicable EU law that can be used in every country of the EU is inherently very difficult.
However, one well-known phenomenon is the so called “gold plating” of directives by national bureaucracies and legislatures, who use the need to pass implementing legislation as an opportunity to enact much larger, more extensive, complex and wide-reaching items of domestic legislation, while placing the blame for the whole on Brussels. From a legal perspective, one can generally argue in court if national implementing legislation ‘under-implements’ or contradicts the directive; it is very difficult to protest that it went too far, directives generally being a “floor but not a ceiling.”