The Non-Marital Presumption

Abstract The question of how legal parenthood should be determined has long been the subject of extensive scholarship. The emergence and expansion of assisted reproductive technology alongside changes in family structures have prompted scholars and policymakers to shift their focus regarding the law surrounding parentage determination. Rather than relying solely on biology, they now also consider the intent to become a parent as well as the parental function. We argue that, while intent, parental function, and biology are all valuable factors in determining parentage, each has its own limitations and deficiencies, placing certain family forms in a legally vulnerable position. We therefore seek to intervene in the extant scholarship by spotlighting one factor of parentage determination that is largely sidelined: the intimate-partner relationship between two prospective parents. We anchor our approach in a preserved and widespread legal tradition—that of marital presumption, which determines that the husband of a child’s mother is the legal father of that child—but reinterpret it to better correspond to the realities of family life in the twenty-first century. We argue that, while the institution of marriage per se is becoming less relevant in determining parentage, the nature of the intimate relationship between the prospective parents should be considered central. This understanding is the basis for the non-marital presumption we develop and offer here. To underpin the foundations of our legal approach, we offer a novel comparative analysis to contrast the legal systems of the United States and Israel, examining the unique, yet overlooked, role that the intimate-partner relationship has played in determining legal parentage over recent decades. We show that, despite the increasing prominence of biology, intent, and function in this arena, the intimate-partner relationship has served—and continues to serve—a crucial role in both legal systems. In light of the legal trend identified here, we then propose and defend a new position, viewing the intimate-partner relationship as a standalone factor for the purpose of at-birth parentage determination. Notably, in the proposed approach, when a child is born into a committed, intimate, partnership—be it opposite- or same-sex, married or unmarried—then both parties to that partnership will be presumed to be the legal parents of the child. This is a non-marital presumption that we call the coupledom-based presumption. Further, we argue that the coupledom-based presumption has the potential to improve how the law relating to parentage determination is currently framed in two complementary ways. First, it responds to the reported shortcomings of other common factors for establishing parentage. Importantly, it helps accommodate the nuanced needs of many families that, at present, remain unmet—primarily, unmarried couples, same-sex couples, and families from lower socio-economic backgrounds. Second, even where applying this presumption might not lead to a significantly different outcome, it actively supports other worthy values—mutual commitment, care, and trust—that are much-needed in the parenthood context. To demonstrate its fitness-for-purpose, we develop its criteria to exemplify how it could be applied to different life scenarios.