Is non-conforming use the civil equivalent of ex post facto?
Ahh!! But, *yes*, any attempt to penalize or criminalize the owners of those long-standing red houses would be ex post facto. Not allowed. Our constitution absolutely forbids it. In this hypothetical, the law forbids the NEW painting red of currently non-red houses. The ones that were already red, are “grand-fathered” and are legally allowed to remain as they are.