Western jurisdictions have adopted remarkably diverging legal approaches to address unmarried cohabitation, ranging between contractual approaches, registered partnerships, and default regimes. This article explores to what extent the large diversity in cohabitation law is prompted by socio-demographic factors, legal tradition and family ideology. The experiences from Belgium, Sweden, England and Wales, New Zealand, and the United States suggest that cohabitation law is mostly ideologically motivated, with socio-demographic factors only having a minor impact. Diverging views on the preservation of the traditional family and the autonomy versus protection of the vulnerable partner-spectrum, in particular, seem to form the backbone of a jurisdiction’s preference for a contractual approach, a registered partnership, or a default regime. Path dependency brings an important nuance to this model. Because existing rights and benefits often prove difficult to turn back, a shift in policy generally fails to eliminate all traces of the former legal framework.

中文翻译：

---

一个趋势，一个拼凑的法律。西方世界同居法为何如此不同的探索

西方司法管辖区采用了截然不同的法律方法来解决未婚同居问题，包括合同方法、注册伙伴关系和违约制度。本文探讨了社会人口因素、法律传统和家庭意识形态在多大程度上促进了同居法的巨大差异。比利时、瑞典、英格兰和威尔士、新西兰和美国的经验表明，同居法主要是出于意识形态动机，社会人口因素仅产生轻微影响。尤其是在保护传统家庭、自主权与保护弱势伴侣群体方面的不同观点似乎构成了司法管辖区偏爱合同方式、注册合伙或违约制度的基础。路径依赖为这个模型带来了一个重要的细微差别。由于现有的权利和利益往往难以逆转，政策的转变通常无法消除前法律框架的所有痕迹。