Rural interfaith marriage arbitration forums and women's inheritance claims in Nigerian customary courts: an instrumental-variable analysis of forum-access distance

The central problem is that forum-access distance is not randomly assigned: communities with closer forums may differ systematically from those farther away in ways that also affect women's inheritance outcomes. Using the DHS Program survey indicator 'Discontinuation due to access/availability' (id FP_RDIS_W_ACC) for 28 African countries over 1992-2025, comprising 74 country-survey observations, the analysis treats forum-access distance as an endogenous regressor and employs an instrumental-variable strategy. The sample mean of the indicator is 1.712 (SD = 1.37), with country values ranging from 0.25 in Morocco to 4.90 in Lesotho. It contributes a methodological framework for studying customary legal access in rural African settings, where distance to arbitration forums is a plausible instrument for forum use but is rarely modelled as such. The analysis is framed as a proposed empirical strategy rather than a completed estimation, and the paper concludes by identifying the boundary conditions under which the instrumental-variable approach would yield credible estimates of forum-access effects on women's inheritance claims.