Why do Medinan surahs include more social and legal regulations?

Medinan surahs (or Madaniyyah) are often associated with social and legal regulations because, following the Hijrah in 622 CE, Medina became the administrative capital of a steadily expanding Islamic state.2

Unlike the earlier Meccan period, this era required the establishment of a functioning society. The Prophet Muhammad worked to integrate the early Muslims (muhājirūn) with the local clans of Medina (anṣār) to form a unified community, or ummah. Agreements such as the Constitution of Medina were necessary to regulate relations between these groups and other populations, such as the Jewish settlers in the oasis. Consequently, the revelations received during this period provided the necessary framework to govern the political, social, and legal affairs of the nascent state.123