Hrmmm....
BD Wong, as Dr Huang, in Law & Order?
I don't really watch Law & Order, but looking him up, I'd say if you're a psychological profiler, you'd probably fall into the character archetype of using Knowledge and study to overcome the world, like a Gil Grissolm or Hermione Granger.....I don't know the character at all though.
Well lets boil down your 3 statements further:
a person who acts as intermediary between the natural and supernatural worlds, using magic to cure illness, foretell the future, control spiritual forces, etc.
OK - So healing & foretelling are effects, so they can go. Natural spiritual worlds are genre specific, so get rid of those. Control of some kind can stay.....so we have
"A person who acts as an intermediary and exerts control"....
a tribal healer who can act as a medium between the visible world and the spirit world.
Most of this is genre fluff, but Tribal can probably stay - this archetype isn't a "lone wolf" type character, and is linked to place or culture (Hence the bleed over with Druid)
a person who is thought to have special powers to control or influence good and evil spirits, making it possible for them to discover the cause of illness, bad luck,
Pretty similar to the first statement once you pull genre and affect, but reinforces control and adds "Influence" to the mix, and also identifies that there is a specific problem that needs solving. "A Goal"
Soooo....that leaves us with an archetype of "A person who acts as an intermediary for a place or culture, and exerts control or influence over others to achieve a specific Goal."
OK, as we are doing this in reverse (ideally you'd be looking at characters archetypes first, not retrofitting an existing D&D class concept), the first question is: Does this wash as a heroic character archetype we see in fiction? In this instance, I'd say yes. There's a little bleed over with the archetype of a defender or avatar of a Place or Culture, but they tend to be resisters and inward looking.
So secondly then, how would you fit that into the Legal Thriller genre.....Well, if your 'place or culture' was the Judiciary system, then the character would be someone who inherently uses other peoples resources, via internal structure or external contacts, to solve legal problems - You see a lot of "fixer" characters who 'know a guy' in various departments who 'knows about this stuff' - Or Lawyers with a team of researchers who are standing at the apex of a network of expertise, bringing it to bear on a single case.
Et voila! There's your Legal Shamanic Character Archetype....
And of course, now you've got that baseline archetype, you can start applying it to other genres, and flexing the definitions. So a Vampire doesn't just 'control or influence', but consumes as well.