Hmmm. This is a tricky one, especially when dealing with part-humans like White Court Vampires and Red Court Infected.
I'd argue that while only spellcasting breaks the laws (the 'inherent' supernatural powers of WCVs and RCIs can't give them Lawbreaker, obviously), those beings are still human enough to get Lawbreaker. A White Court Vampire wouldn't get Lawbreaker from mind-whammying someone with Incite Emotion, but he would if he used psychomantic Thaumaturgy (presuming he had that power). The Wardens wouldn't go after someone belonging to another Accorded nation, though.
I'm not sure about things like Seelie/Unseelie Magic and Sponsored Magic, though. I kind of think the Knights should not get Lawbreaker, as being the Queens' assassins is a big part of what they're *for*, but...