683. No punishment without law, proportionality of offences and penalties, and double jeopardy.

The EU Charter provides that no one is to 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, and nor should a heavier penalty be imposed than the one that was applicable at the time the offence was committed1. This does not prejudice the trial and punishment of any person for any act or omission which, at the time when it was committed, was criminal according to the general principles recognised by the community