Magic that affects the mind is not itself against the Law (either at the Council Law level or the Universal one). That's a big part of why it took two different Laws to cover it. One is against mental Breaking & Entering, and the other is Thralling a person which is a fairly specific (if comprehensive) magical act; both directly Subvert Free Will. There are tons of mental magics that do not qualify, from the various Communication Spells we've seen, general deterrence wards and whatever else the Council uses when they meet (or execute) in Chicago, that Memory defense Spell of Elaine's, that Truth Spell of Luccios (I think), that Dont Notice Me potion from FM, the any phantasm-based illusion, etc etc.
In the case of the Potion, it upped the crap out of her sex drive but from the outside it's hard to say it if was a chemical vs a psychological effect. Neither would qualify as full Thralling or as Mental B&E like implanting a Nightmare would be. Hell, I could see the argument that Molly wouldnt have been breaking the laws if she'd just evoked an ambient fear response each time she witnessed her friend Using, instead of actually Implanting a persistent Nightmare.