With the increase in volume and importance of cross-border investigations in the EU, ensuring the admissibility of evidence gathered in another Member State at trial is crucial − both for efficient law enforcement and for the protection of fundamental rights. At present, the rules on the collection, use, and admissibility of evidence are left to the laws of national criminal procedure of the Member States. These differ extensively as to the collection, use, admissibility, and nullity of evidence and thereby act as an obstacle to the use of cross-border evidence. In order to overcome the present difficulties, this article argues in favour of a new legislative proposal based on Art. 82(2) subsection 2 TFEU laying down common rules for the admissibility and exclusion of evidence in criminal proceedings.