To rethink law and its plurality, it is essential to consider how categories of law such as customary law, religious law or state law are formulated. The customs of Adivasi (tribal) communities in India have been extensively documented by anthropologists who have often categorised these under the adjective of customary law. This paper examines the normative values and customs understood to be Adivasi customary law by considering custom which is codified and given a legalistic form by members of the community themselves. The Chaudharis, an Adivasi community in South Gujarat, India, were part of inter-tribal meetings called the Raniparaj Parishad since the early 1900s and involved in subsequent social reform movements in the 1920s. A group of Chaudhari leaders drafted a set of written rules in 1929 and published their first Bandharan, or constitution, in 1949 in an effort to reform their customs around marriage, divorce and inheritance. The new constitution was written with the intention of changing customs to counteract the stronghold of moneylenders and exploitative state policies. To what extent can legal ordering and legalistic form be found outside of state law? Drawing on my ethnographic fieldwork in the South Gujarat region of India for my doctoral thesis, I will discuss the historical and ongoing processes of defining and redefining custom and ‘customary law’ by members of the Chaudhari tribe through written constitutions and oral traditions. This is an example of how customs formulated by the codified written constitutions can be dynamic and self-consciously transformed by the community in response to their socio-economic needs. I argue that rather than being static placeholders for tradition, custom and the adjective of customary law become spaces that undergo constant revisions in the various versions of the Chaudhari constitutions.