Born at Tenkodogo, Tiao attended a seminary from 1969 to 1974 and studied to become a priest, but he abandoned that pursuit upon concluding that his left-wing views were incompatible with a career in the Church.
Lahir di Tenkodogo, Tiao bersekolah seminari pada 1969 hingga 1974 dan belajar untuk menjadi seorang imam, tetapi ia meninggalkan sekolahnya itu setelah menyimpulkan bahwa pandangan sayap kirinya tidak sesuai dengan karier di Gereja.