Final answer:
The Supreme Court refusing to hear an appeal challenging a state law prohibiting gambling in association with horse racing is an example of judicial restraint.
Step-by-step explanation:
The Supreme Court refusing to hear an appeal from a group challenging a state law that prohibits gambling in association with horse racing is an example of judicial restraint. Judicial restraint is a theory of judicial interpretation that encourages judges to limit the exercise of their own power and defer to the legislature. In this case, by refusing to hear the appeal, the Supreme Court is letting stand the state law, showing restraint in overturning the decision.