2) The Court is asked to examine this issue in the light of the Charter of Fundamental Rights of the European Union. The third sentence of Article 49(1) of the Charter establishes the principle of the retroactive application of the more lenient criminal law (lex mitior), a principle of considerable practical importance the interpretation and application of which the Court of Justice has already addressed on many occasions. ( 2 )

...

6) The EU law framework applicable to this case is determined in essence by Article 49(1) of the Charter of Fundamental Rights of the European Union. In addition, reference must be made to Article 4(3) TEU and Article 325(1) TFEU, as well as to Regulations (EU, Euratom) No 966/2012, ( 4 ) (EEC) No 1964/82, ( 5 ) (EC) No 2469/97 ( 6 ) and (EC) No 1359/2007. ( 7 ) On the other hand, Regulation (EC, Euratom) No 2988/95, ( 8 ) which has been mentioned by a number of the parties to the proceedings, is not material, being concerned only with administrative-law penalties but not with criminal-law penalties to protect the financial interests of the European Union.

...

7) The principle of the legality of penalties is established as follows in Article 49(1) of the Charter of Fundamental Rights: ‘No one shall be held guilty of any criminal offence on account of any act or omission which did not constitute a criminal offence under national law or international law at the time when it was committed. Nor shall a heavier penalty be imposed than that which was applicable at the time the criminal offence was committed. If, subsequent to the commission of a criminal offence, the law provides for a lighter penalty, that penalty shall be applicable.’

...

27) By judgment of 23 November 2016, received on 6 March 2017, the Cour de cassation (Court of Cassation, France) referred the following question to the Court of Justice for a preliminary ruling under Article 267 TFEU:

Is Article 49 of the Charter of Fundamental Rights to be interpreted as precluding a situation in which a person is convicted on the ground that he obtained export refunds, to which he was not entitled, by means of deceitful practices or the making of false declarations as to the nature of the goods in respect of which the refunds were respected, although, as a result of changes in the rules which occurred subsequent to the facts of the case, the goods that were in fact exported by that person have since become eligible for those refunds?

....

30) By its request for a preliminary ruling, the Cour de cassation (Court of Cassation) asks the Court of Justice to provide an interpretation of the third sentence of Article 49(1) of the Charter of Fundamental Rights of the European Union, which establishes at EU level the principle of the retroactive application of the more lenient criminal law.

31) The defendants fear that the rights they derive from the third sentence of Article 49(1) of the Charter could be sacrificed on the altar of efforts to combat as effectively as possible fraud that operates to the disadvantage of the financial interests of the European Union. That fear is unfounded, however. It goes without saying that the protection of the financial interests of the European Union may be ensured only by means consistent with the rule of law. ( 19 ) It follows, moreover, that the elementary procedural guarantee enshrined in the third sentence of Article 49(1) of the Charter is enjoyed by anyone prosecuted under criminal law in a situation governed by EU law, and nobody can deny the defendants the enjoyment of the rights thus conferred on them. This case, however, calls for a clarification of the precise content of the principle of the retroactive application of the more lenient criminal law.

...

32) In accordance with Article 51(1) thereof, the Charter of Fundamental Rights is applicable ratione materiae in the present case, since the issue of the retroactive application of the more lenient criminal law arises here in the context of the implementation of EU law by the national authorities. The latter are involved in the payment and monitoring of EU special export refunds on meat of bovine animals and, as such, have a duty to protect the financial interests of the European Union, including through the imposition of effective, proportionate and dissuasive penalties (Article 4(3) TEU, Article 325(1) TFEU and Article 59(2) of Regulation No 966/2012). ( 20 )

33) Moreover, the application of the third sentence of Article 49(1) of the Charter of Fundamental Rights is not precluded by the fact that the offences prosecuted by the French justice system in the present case took place before 1 December 2009, that is to say before the date on which the Charter, on the entry into force of the Treaty of Lisbon, became legally binding and acquired constitutional status (see in particular Article 6(1) TEU). The Charter provision to be interpreted here, after all, establishes a general principle of EU law which, even before the Charter entered into force, was based both on the constitutional traditions common to the Member States ( 21 ) and on the international treaties concluded by them ( 22 ) and had been recognised by the Court of Justice on many occasions. ( 23 )

...

50) The noble concept which underpins the principle enshrined in the third sentence of Article 49(1) of the Charter of Fundamental Rights would thereby be turned on its head.

...

51) All things considered, therefore, the principle of the retroactive application of the more lenient criminal law (third sentence of Article 49(1) of the Charter of Fundamental Rights) does not preclude the punishment of a person who has sought or obtained an unjustified advantage by engaging in deceitful practices or making false declarations as to the nature of the goods in respect of which he is requesting a special export refund under EU law, in the case where the goods actually exported were not eligible for a refund at the time of those deceitful practices or declarations and became so eligible only by reason a change in the rules of EU law that took place after the offence was committed.

...

54) Does it make any difference, for the purposes of assessing the present case from the point of view of the third sentence of Article 49(1) of the Charter of Fundamental Rights, whether the defendants in the main proceedings are prosecuted under criminal law for actually obtaining such an unjustified financial advantage for their undertaking or only for practices pursued with fraudulent intent to secure such an advantage?

...

59)  I shall confine myself to making the point that the applicable EU law remained constant inasmuch as the special export refunds in question were only ever available for fresh or chilled meat of bovine animals, but never for frozen meat of bovine animals. So far as concerns their criminal liability for any false statements made by them with respect to the degree of freshness of the cuts of meat concerned, therefore, the defendants in the main proceedings are precluded from the outset from relying on the retroactive application of a more lenient criminal law within the meaning of the third sentence of Article 49(1) of the Charter of Fundamental Rights.

...

60) In the light of the foregoing considerations, I propose that the Court reply as follows to request for a preliminary ruling from the Cour de cassation (Court of Cassation, France):

The third sentence of Article 49(1) of the Charter of Fundamental Rights of the European Union is to be interpreted as meaning that it does not preclude the punishment of a person who has sought or obtained an unjustified advantage by engaging in deceitful practices or making false declarations as to the nature of the goods for which he is requesting a special export refund under EU law, in the case where the goods actually exported were not eligible for a refund at the time of those deceitful practices or declarations and became so eligible only by reason of a change in the rules of EU law that took place after the offence was committed.