[philman_36]

You left something out...
The de facto officer doctrine confers validity upon acts performed by a person acting under the color of official title even though it is later discovered that the legality of that person's appointment or election to office is deficient. Norton v. Shelby County, 118 U.S. 425, 440 (1886).

Some of that decision...
While acts of a de facto incumbent of an office lawfully created by law and existing are often held to be binding from reasons of public policy, the acts of a person assuming to fill and perform the duties of an office which does not exist de jure can have no validity whatever in law.
An unconstitutional act is not a law; it confers no rights; it imposes no duties; it affords no protection; it creates no office; it is in legal contemplation as inoperative as though it had never been passed.

[wideminded]

"While acts of a de facto incumbent of an office lawfully created by law and existing are often held to be binding from reasons of public policy, the acts of a person assuming to fill and perform the duties of an office which does not exist de jure can have no validity whatever in law."

The office of President of the United States exists de jure.

The office of Board of Commissioners of Shelby County apparently did not.