This will come as a great shock to all the attorneys in the group. They've always been under the impression that US law is quite explicitly based on common law except where modified by statute or constitutional provision.
The only State that uses civil law is LA, a hangover from its period under French control.
I didn't write that bit, I just put it up for Kansas to chew on, I am seeing references to this stuff but its deep, life is too short to follow this unless I have good reason rather than this being a distraction.
So my advice is to have it out with the guy who wrote that piece.