If there was a specific federal law or specific constitutionally granted federal power cited by the court, then the supremacy clause would be applicable: "This Constitution, and the Laws of the United States which shall be made in pursuance thereof; and all treaties made, or which shall be made, under the authority of the United States, shall be the supreme law of the land; and the judges in every state shall be bound thereby, anything in the constitution or laws of any state to the contrary notwithstanding."
On the other hand, when there is no federal law or constitutionally granted power in play or cited, then the tenth amendment would seem applicable to any court decision: "The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people."
Otherwise I'm staying out of this debate. Just thought I'd put in my two cents on this particular aspect.
