Just to complicate things further the standard of proof in criminal trials isn’t universally applied as being ‘sure’.
Certain defences, if raised by the defence, require the mental gymnastics of the jury/tribunal of fact applying the balance of probabilities to that particular defence in conjunction with being sure the offence has been made out more widely by the prosecution.
So two standards of proof for one offence.
Any statutory due diligence defence for a regulatory offence, once raised, requires the application of this standard of proof, with the burden of proof resting with the defence, in respect of that defence, once raised by them. The burden of proof for the jury being sure of guilt for the index offence rests with the prosecution.
Hopefully that further clears things up…