I'll demonstrate again that I am not a lawyer. The word “deterrence” signals—to me, anyway—that perhaps there's some criminality involved for which a penalty of some sort should apply, as opposed to somebody just doing the wrong thing. For instance, an administrative monetary penalty, if it was stiff enough, could do the job of deterrence, so that if you get nailed once, you get nailed again.
The idea is to make sure that the right thing is done. I think that if in fact there's an inference that deterrence might have to involve some test of criminality, that could complicate the matter.