I suggest you read this From the EUropean Commission
Application of EU law - European Commission
AIUI you are wrong. If you were to be prosecuted you would not be prosecuted for an offence against EU Law but for an offence against the National Law of the prosecuting State. It is up to EU States to incorporate EU Law into their National Law and, as the reference states, it is for the EC to monitor and take action if they believe it has not been done properly.
The ongoing controversy over the rights of prisoners to vote in UK elections is one such example.