[The_Victor]

What oath binds them to treat previous court decisions as law even though the Constitution never gave courts legislative authority?

The oath to uphold the law. I will not hold an appellate court judge responsible for upholding a USSC decision. The lower courts have no choice. If you think the appellate court judge should break his oath then you're no better that the USSC justices that provided the bad ruling in the first place.

[The_Eaglet]

Where does the Constitution give appelate courts legislative authority?