Not really but when a EU directive is decided, the member states have x months to translate it into national law. It's still the law of the specific country th

Not really but when a EU directive is decided, the member states have x months to translate it into national law. It's still the law of the specific country that applies: but, simply, each country has to adopt the EU directive. It's kinda more complicated than this as many european states are divided into regions, so for many matters it's not even the individual states transposing the EU directives into national laws but regions transposing the EU directive into regional laws. One example would be the EU deciding, a few years ago, that the age for cars to be considered "old timers" is 30 years. Before that some regions had 20 years, others 25, others 30, etc. Then all the regions had to adapt their legislation. In a single country, like Belgium, the three regions all transposed the laws in varying ways (and at different times). But in the end the result is the same: all european regions have "harmonized" the notion that an oldtimer is a vehicule 30 years old or older. Now there are several matters on which the EU has no authority whatsoever. For example the EU has no fiscal authority: fiscality is decided by the countries/regions and the EU can shut the fuck up. (so far).