The Voivodeship Administrative Court (VAC) in Warsaw in a judgment of 8 April 2010, case file III SA/Wa 396/10, ruled that there is no legislative impediment to the existence of a mixed system for the storage of invoices, which consists of sending an invoice in paper and storage of its electronic copies with the option to print at the request of a legitimate authority. Such an interpretation was corroborated by teleological considerations, environmental and economic. According to the VAC the different findings would lead to a breach of the principle of proportionality, as set out in article 5(3) of the Treaty on European Union.
3. Under the principle of subsidiarity, in areas which do not fall within its exclusive competence, the Union shall act only if and in so far as the objectives of the proposed action cannot be sufficiently achieved by the Member States, either at central level or at regional and local level, but can rather, by reason of the scale or effects of the proposed action, be better achieved at Union level.
The institutions of the Union shall apply the principle of subsidiarity as laid down in the Protocol on the application of the principles of subsidiarity and proportionality. National Parliaments ensure compliance with the principle of subsidiarity in accordance with the procedure set out in that Protocol.
Consolidated versions of the Treaty on European Union and the Treaty on the Functioning of the European Union, Official Journal C 83 of 30 March 2010. PDF files.