Following the Action Group crisis of May 1962, the declaration of emergency in the Western Region, and the establishment of the Coker Commission of Inquiry, Chief Obafemi Awolowo and 24 co-accused (including Anthony Enahoro and Lateef Jakande) were charged with conspiracy to overthrow the Federal Government by force. The trial opened before Justice Sowemimo at Lagos High Court on 2 November 1962 and lasted ten months.
The prosecution case rested heavily on the testimony of Chief E.O. Oduola (an Action Group treasurer turned state witness) and on documents seized from the Action Group office. Awolowo was convicted on 11 September 1963 and sentenced to ten years' imprisonment. He served three years at Calabar Prison before being released by Yakubu Gowon in August 1966 and immediately appointed Commissioner for Finance.
The trial broke Western Region politics, and its political character has been a fixed point in Yoruba political memory ever since.