I dunno if this might a case of it being Harry's personal thoughts and not actual canon, but I'm going through the series again right now, and in book 4:
The WalMart is filled with a mind-fog that simply stuns everybody and makes them stand still without causing harm, and Harry says it's still a "clear violation of the laws", if I recall correctly.
The third law is cut and dry. Dresden is talking about the fourth law here. Enthrallment is a pretty big area, which is why it's harî to arbitrate mental stress. I'm taking the extreme side - mental stress = lawbreaking - mainly for debate, to see what people come up with in response, because personally I see that line as so... undefined... that anything could be argued. And while as an ST, where that lawbreaker line is fuzzy to me, I don't think it's so fuzzy for the greycloaks.
As for the soap: I'll actually argue against "just intention". There's intention TO kill, and then there's carelessness. Dresden time and time again avoids using magic in a way that could be potentially deadly as a side-effect, despite his regular burning of buildings. While examples of where his magic might have hurt mortals accidentally can surely be brought up, it's clear that he tries to avoid this. Thus, while the soap person would probably get off free (who the crap expects someone to die of bubbles, even accidentally), the guy who ices the stairs of the library to slow down his pursuers certainly does get hammered if one of his pursuers breaks a neck in the fall, as does the guy who magically burns down the warehouse going "is anyone in there? oh i don't care." While the guy who has been told/ has checked and thinks that warehouse is empty would be okay. Now, these may be situations where the council will set the DOOM! if given a good reason to, but still.. some swordy mcswordertons might think even Mr. Bubbles needs a lesson. Slippery Slope is kind of a warden thing.... the whole torture a puppy as a child, become a serial killer later on bit? Their response is often "off the kid."