After military rule ended in 1999, traditional Sharia Islamic law was reintroduced in several northern Nigerian states. The source states that courts enforcing Sharia existed in twelve states. The system became a major expression of Islamic political and legal authority in the north, where Muslims formed a large majority of the population.

Sharia law is presented as deriving from the Koran and prescribing specific punishments for particular offenses. The source gives examples of corporal penalties for theft and premarital sex, emphasizing that punishments could be applied without regard to circumstances. These practices caused concern among Christians who believed that Islamic courts did not treat them equitably.

The issue also brought local Islamic authorities into conflict with Nigeria’s national government and constitution. The constitution placed Nigerian citizenship before religious identity, while many Muslims argued that Sharia should retain equal or greater authority. In 2002, the national government overturned a local ruling that sentenced a woman to death by stoning for adultery, illustrating the institutional dispute.