The Supreme Court can overturn a lower court's decision on a case by granting a writ of certiorari, which means they agree to hear the case. Once the case is before the Supreme Court, they have the authority to review the lower court's decision and reach a different conclusion. The Supreme Court is the highest court in the land and its decisions are final and binding, so when they overturn a lower court's decision, it is considered the final decision on the case.
