Patrilineal kinship system and the customary inheritance law of Batak migrant families in the modern Indonesian family: is gender equality still the problem?

The Batak ethnic group is one of the Indonesian ethnic groups that adheres to a patrilineal kinship system. Many Batak families, however, have migrated beyond their place of origin and have long been settled in their new areas. This study aims to determine the degree of implementation of Batak customary inheritance law and discern the extent to which customary law is maintained or has shifted regarding gender equality. This study adopted an empirical juridical research method using a qualitative approach. The data collected comprises both primary and secondary data. The research found that Batak migrant families in Central Java are bicultural because they generally maintain a cultural attachment to their customary inheritance law while adapting in many respects to the different cultures encountered in their new place of residence. Some utilise aspects of Batak customary inheritance law, primarily the principle that male offspring receive most of the inheritance, while female offspring receive only a very small portion. Bierstedt, in his theory of legal culture compliance, attributes such compliance to the processes of indoctrination, socialisation, and habituation, as well as to considerations of utility and group identification.