In a detailed historical review of Timothy Sandefur’s new book entitled The Conscience of the Constitution, Adam Tate raises the practice of federalism as a principled method that representatives used in the early republic for handling difficult issues. Rather than face political paralysis or endure efforts at national coercion via constitutional provisions regarding slavery or religious freedom, for example, Tate notes that the Founders looked to the states and their separate interests as the best solution. So Tate argues that there was no natural rights code of law with exact specifications nationally applied.
If we were such a republic, then why were natural rights not relied upon in the tough cases and appealed to with precision? If there was consensus on natural rights as the baseline, then surely it would have governed these disputes, rendering them noncontroversial. More plausible is that the natural law and natural rights were seen as an ultimate source of law, but what this meant in concrete application was not firmly agreed upon by the Framers. As a result, particular resolution of constitutional questions via a detailed code of natural rights wasn’t ventured.