Self-determination vs. state sovereignty. What are the determinants of agreed-upon independence referendums in liberal democracies?

Secession referendums can help to resolve the tension between self-determination and state sovereignty. Nevertheless, not all state governments accept holding such consultations in collaboration with secessionist movements. This article tackles this issue by focusing on the determinants of agreed and non-agreed upon independence referendums. Through a statistical analysis based on a dataset of independence referendums held in liberal democracies from 1945 to 2022 (N = 70), we demonstrate that the decision of the parent state's government to agree to an independence referendum depends on two factors. The first is the perception of competition and/or electoral proximity to the referendum demand. The second depends on the expectation of the low cost of an eventual secession – at least in terms of population, area and natural resources. Accordingly, we propose a general model designed to predict the disposition of a liberal democracy to agree to an independence referendum.