It goes back a long way to Marbury v. Madison when the Supreme Court decided that it is the final arbiter in matters legal and Constitutional. In the early 19th Century, in Barron v. Baltimore it was decided that the Constitution and the amendments only applied to the feds. Any corrections will be appreciated.
I agree that is what they are basing that thinking on. I don't agree that it is origionalist.
To me origionalist means basing the opinion on what the framers had in mind at the time.