The European Court of Justice has heard legal arguments from EU member states whether electronic communications obtained by an international police operation to hack the EncroChat encrypted phone network can be lawfully used as evidence in courts in the European Union. Prosecutors from France, Germany, the Netherlands, Spain, Hungary, Sweden, the Czech Republic, Ireland, gave oral evidence to the Court of Justice of the European Union (CJEU) in Luxembourg during a seven hour hearing yesterday in a complex case focusing on European law. Defence lawyers believe the case could have implications for hundreds of prosecutions of people accused of drug dealing and organised crime on the basis of hacked messages from EncroChat, and another encrypted phone network, Sky ECC, where there is no supporting evidence of criminality, if the CJEU finds there were breaches of EU law.