i would say the grand master of the self-righteous path would be Sagittarius- so a sag ascendant with a heavily debilitated jupiter or a jupiter with some squares by saturn mars and pluto in a house that he doesnt like would do the trick - but FOR SURE jupiter or the ascendant would be in a fire sign- 10000 percent
sag is the sign of truth, beliefs, preaching, religion, the law, morals etc etc- but getting carried away- overdoing it- going too far with something is also a very jupiterian trait- and thinking you are so morally right and believing in what you are preaching- and not hearing any other side and denouncing any other belief because you KNOW you are right- is also very very jupiterian
being very blunt and straight-forward and extremely honest as well.....
and because usually these folks are not hypocrites- they truly walk the walk- they would rather cut off contact or denounce something- than to know that they are somehow affiliated with someone/something that is so against/different what they believe is to be rightful- thats not how they roll- thats not who they are and again, they are not hypocrites- when they truly believe something- they will stand by it no matter what- defending it and fighting for it!
as happy go lucky optimistic as sag and jupiter are- this would definitely be one of the more negative traits
i think one of the things that very well apply to sag/jup in these cases is- my way or the highway!
there are others but this is the first one that popped in to mind