What is the test for making a claim of unconstitutionality?

Generally, but not always, it is required that the claim of unconstitutionality be raised at the first opportunity. Before taking their appeal, decisional law was adverse to appellants. Clearly, had appellants raised the question in the trial court, their urging necessarily would have been ruled against since the trial court was bound to accept and apply the law as it then existed under intermediate appellate court decisions. We hold the appellants have raised the question at the first opportunity, following decision in Brown v. Merlo, by their opening brief in this appeal.