Key facts of the case:
The petitioner filed an action against the decision of the defendant that set up the correct amount of tax the petitioner was due to pay after international investigation of his actual income. The regional administrative court dismissed his action and approved the decision of the defendant in the 1st instance. The petitioner challenged the ruling before the Supreme Administrative Court and claimed, inter alia, that he had the right to be present at the investigation conducted in other States and to respond to the information, which they provided to the defendant. The Supreme Administrative Court concluded that part of the questions at stake concerned EU law.