Scholars and policymakers in the West commonly hold that liberal countries that intervene to stop genocide subsequently ought to establish democratic political institutions to enable peaceful collective self-determination. I argue that this guidance is problematic. First, introducing electoral democracy in deeply ethnically divided societies – especially but not only after genocide – often results in either tyrannical majority rule or deadlocked decision making rather than inclusive self-determination. Second, normatively speaking, John Rawls made a strong case that inclusive self-determination can be achieved through ‘decent,’ less than democratic political structures that enable group-based representation. Bringing these insights together, I argue that particularly for postgenocidal societies that lack prior experience with liberal democratic rule, outside interveners should stop short of actively promoting full electoral democracy and instead consider promoting hybrid political institutions that combine popularly elected bodies with customary authority structures. Such hybrid institutions can prevent tyrannical majority rule as well as decision-making deadlock; they are also likely to fit better with local culture; therefore, they may offer a more robust foundation for peaceful self-determination. A discussion of hybrid institutions in postwar Somaliland and Bougainville illustrates how these arrangements can facilitate peaceful self-determination in practice.