This chapter explores the unique function and role of judicial documents – a significant form of informal state law, as distinguished from formal statutory laws – in China’s legislative enterprise. In particular, it examines why and how, with no explicit statutory delegation, the judicial lawmaking practice of producing judicial documents has become embedded in the adjudication of China’s courts. It accordingly proposes a twilight theory of China’s judicial documents that explains why the practice of judicial lawmaking through producing documents exists in a twilight zone between legal and illegal and is suitable for China’s politically resilient authoritarian regime. Moreover, it demonstrates how the judicial document can be referred to effectively by judges in adjudication. It further investigates the extent to which the judicial document has enabled the court, under the dual leadership of the superior court and the local Party committee, to efficiently and effectively respond to the subnational diversity and the differences of local politics.