'I still don't see how they can legislate such a thing.'
It's simple: if I hold your family hostage, I can legislate anything I want.
'When the cats away the mice will play,'
Yes, but in this case if the cat is away, it is because he is eating another mouse. The lesson will not be lost on the remaining mice.
'...and they can't watch all of us all of the time.'
They dont have to. They need only make an example of a few of us. The rest will fall into line. Face it: we're cowardly, lazy, and stupid, or we wouldnt be in this situation in the first place.