Empirical constitutional studies: The state of the field

Abstract This Foreword takes stock of the rapid rise of empirical studies on constitutions and constitutional law. It traces the field’s development from large-scale coding of written constitutional texts to more recent data collection efforts that capture the “small-c” constitution, including measures that capture how the constitution has been interpreted and applied, costitutional law-related event-based datasets, expert surveys, cross-national opinion data, and experimental data. It also highlights a parallel methodological shift: from largely descriptive accounts of global constitutional patterns to explanation-oriented research that seeks to identify causal relationships through statistical analysis of cross-national data as well as experiments and mixed quantitative–qualitative research designs. Taken together, these developments mark the field’s shift from a first, text-centered wave to a second wave characterized by expanded data and causal inquiry. Along the way, this literature has documented major global trends—frequent constitutional replacement, increasing length and detail of constitutional texts, proliferating rights and duties, increasingly participatory constitution-making processes, and the spread of unamendability rules—and has begun to ask hard questions about their consequences. For example, emerging research suggests that constitution-making might be riskier than previously thought, that constitutional verbosity and rights proliferation may carry costs, that compliance gaps are common, that courts and eternity clauses rarely halt democratic erosion, and that constitutional arguments do not reliably override partisan preferences. At the same time, the Foreword emphasizes that these findings are provisional and probabilistic, that is, not definitive verdicts but evidence about the expected risks and trade-offs associated with different constitutional choices, andsubject to refinement and revision as new data and methods emerge. Finally, this Foreword engages three central critiques of the field: that constitutional texts are too indeterminate to permit meaningful comparison; that cross-national research abstracts away from local context in ways that render comparison meaningless; and that causal inference with observational cross-national data is hopelessly confounded. The Foreword argues that while each of these critiques represents a genuine challenge, none of them is fatal. Constitutional texts frequently contain a discernible core that can be systematically studied; context matters, but if we overemphasize it, comparison becomes impossible; and although causal identification is difficult, careful research design—particularly the use of mixed methods—can generate credible, if always provisional, inferences.