Which authority is NOT binding when defending a state law claim in a trial court?

In the context of defending a state law claim in a trial court, the authority of federal decisions is not binding. This is because the primary jurisdictional authority for state law resides within the state's legal framework and its courts. Therefore, while federal court decisions may be persuasive or informative, they do not have the same binding authority over state law claims as decisions made by the state's own supreme court or appellate courts.

State supreme court decisions are binding on all lower state courts, as they represent the highest level of authority regarding state law. Similarly, decisions from appellate courts within the state are binding on trial courts within that jurisdiction, providing clear guidance on legal standards and interpretations relevant to state law claims. In contrast, district court rulings do not establish precedent and can only serve as persuasive authority, often limited to their own jurisdiction.

Thus, the correct choice highlights the distinction between binding and non-binding authority when addressing claims rooted in state law within the framework of a trial court.