Brewing a love potion wouldn't violate the Law, but slipping it to someone against their will might count for the purposes of enforcement. Similarly to owning a gun; I have it, but my use of it is restricted. I don't break any laws until I disobey those restrictions.
Now, here's a question: was the Three-Eye drug Victor Sells brewed illegal by Council Law? Or was it illegal to distribute? Harry says the potions he sees in Sells's clubhouse have a nasty, black-magic-ish aura, but is that just Harry's interpretation of how horribly the potion corrupts the user?
He violated a bunch of other Laws regardless, so he'd be executed no matter what, but if he had just stuck to the drug trade without the murder and demon-summoning, would he have been?