Cute and very fun to read.

Yes, I utterly loved the wording of this mechanic when I saw it. It reads so well and I think it works very well within the rules too.

The idea, naturally, is that there will be several cards that specify something that's against the law, and several cards (mostly overlapping the first set) that specify punishments for players who're breaking the law; the key being all of your Dark Justice effects will trigger if any of the laws are broken.

There is actually one serious rule/templating issue: I don't think the mechanic supports both "continuous" law-breaking, as here, and "triggered" law breaking (as on, say Zhavi Shunner) in an intuitive fashion.

Hm. True. You can't just say "Casting more than one red spell in a single turn is against the law".

Perhaps "Players who have cast more than one red spell this turn are breaking the law"? A continuous ongoing effect that looks at recent discrete events?

Rewrote the trigger and lowered the cost: I figure with that sort of effect, it causes enough trouble to its controller that it can enter earlier.

I'm very tempted to adapt this mechanic for use one day. I like it a lot.

Feel free. After all I didn't come up with the original version either.