Any such law would be used to squash small businesses while larger ones are largely given a pass (even a fine large enough to sting will only sting). See the difference between dealing with known drug money as an individual vs. as a bank.
Then tie it to the company size, or make it big but limit it according to some factor (As far as I remember, here in Germany it limited by a percentage of revenue). And/or add personal liability for people having oversight over this, of course also within limits.
