In pockets across the world, a movement has taken hold to allow fundamentalist1 religious norms, rather than state law, to govern family matters like divorce and inheritance. Many of these religious norms depart significantly from the state's background rules protecting individuals. Nonetheless, fundamentalist religious understandings are given the force of law, either by treating them as binding judgments arrived at through arbitration or by delegating to religious groups to decide family disputes, with nominal state oversight. This Essay explores the risks to two traditionally vulnerable groups, women and children, when the state delegates its traditional oversight of the family to religious authorities.2 To surface these risks, this Essay draws on two lived experiences of religious deference around the world. Specifically, this Essay examines the eighty-five Sharia courts operating in Great Britain today, which apply Islamic, not British, law to divorce and inheritance.3 It also examines the system of shared in Western Thrace, a section of Greece where three Mufti decide family disputes for a Muslim minority of 1 10,000 people.4 While this Essay spotlights experiments to enforce rather than civil understandings of family matters, numerous scholars have advocated for deference to the religious understandings of Christian, Jewish, and other faith groups as well.5 In both places, the civil law supplanted by fundamentalist religious norms would provide considerably more protection to individuals in two periods of great need, upon divorce and the death of a spouse. As this Essay documents, these protections for the vulnerable are hollowed out when harsh religious understandings displace the state's more protective rules, whether in fundamentalist families or fundamentalist families of other faiths. Drawing on systems of deference operating today, Part I shows how women at divorce stand to lose custody of adolescent children and face near certain poverty if certain schools of law govern the proceeding. Part II assesses how a woman's ability to exit a marital relationship, especially a violent one, may be affected by religious deference. This Part argues that religious deference undercuts the state's ability to police family violence. Part ?? then shows that upon a spouse's death, women face equally grave and devastating results under law. The wealth a woman would otherwise receive upon her husband's death under civil law shrivels under law to a mere fraction of the decedent's estate, leaving many women financially at risk. Part IV rejects two articulated justifications for schemes of religious deference despite the inequitable treatment of women - namely, that a woman's natal family will support her financially when the husband does not and that women have voluntarily accepted these outcomes. Policymakers considering schemes of deference in their own countries should consider these inequities before giving effect to extreme religious views that will trap some women in poverty or abusive relationships.6 I. LIVED EXPERIENCES OF RELIGIOUS DEFERENCE Two systems of religious deference operating today provide a snapshot of the risks to women and children in such systems. These lived experiences in Great Britain and Western Thrace demonstrate poignantly that removing state protections from the family is fraught with peril. A. Great Britain 's Embrace of Islamic Divorce In 2008, the British government quietly sanctioned the powers for sharia judges to rule on cases ranging from divorce and financial disputes to those involving domestic violence.7 This system of religious arbitration took root despite a firestorm of controversy that erupted in early 2008 when the Archbishop of Canterbury called for a plural jurisdiction in which Muslims could choose to resolve family disputes in religious tribunals or in British courts. …