Constitutional theory is a mess. Disagreements about originalism and living constitutionalism have become intractable. Constitutional theorists make some arguments that seem clearly fallacious and advance proposals that are pie in the sky. One of the reasons for the mess is an overreliance by constitutional theorists on “outcome reasons,” justifications that rely on the theorist’s beliefs about what outcomes are good and what outcomes are bad. This outcome-drive approach is exemplified by the so-called “canonical cases” argument, which evaluates positions in normative constitutional theory on the basis of its counterfactual implications for a handful of prior decisions of the Supreme Court. Among the many problems with “outcome reductionism” (exclusive reliance on outcome reasons) is the reality that none of the fundamental and feasible options for normative constitutional theory can guarantee outcomes that that most citizens would find acceptable, much less optimal. Living constitutionalism produces constitutional outcomes that reflect the moral values and political ideology of Supreme Court Justices, but over the long run there is no guarantee that the Justices will do what any individual believes is required by justice. Decades ago, the Justices established a constitutional right to abortion, but recently they reversed course. Dramatic changes in constitutional law are inevitable given that the Justices are selected by the President and Congress, institutions that will change their political makeup in unpredictable ways over time.
Outcome reductionism is not a sensible method for normative constitutional theory, but there is a better approach. Outcome reasons can be supplemented by process reasons such as legitimacy, the rule of law, and institutional capacities. The way forward for constitutional theory involves a holistic assessment of both outcome reasons and process reasons via the method of reflective equilibrium. The way forward requires a frank acknowledgement of the consequences of deep and persistent disagreement about fundamental questions concerning justice and the common good. And therefore, the way forward will require an acknowledgement that a legitimate constitutional order will require compromise.