Nairobi, July 21 -- Earlier this year, thousands of Kenyans received an unusual text message from the Kenya Revenue Authority (KRA). Although they had filed nil tax returns, KRA's records showed they had earned income and informed them that a pre-populated return was ready for filing.

No auditor had visited. No inquiry had been made. The system had simply compared what taxpayers declared with information already held from other sources.

That message captured a profound shift in Kenya's tax administration.

The law still rests on self-assessment, with taxpayers declaring their income and the Commissioner retaining the power to verify it. In practice, however, compliance is increasingly determined not by what taxpayers report but by wheth...