In 1977, Obua was the league's top goalscorer, with 24 goals, but after Police were relegated at the end of the 1978 season he joined Maroons FC of Luzira.
In April 1979, the Ugandan dictator, Idi Amin, was ousted and, during the unstable period that followed, several players from Simba FC—a team which, at that time, was drawn entirely from serving Army officers—were arrested.
To avoid a similar fate, Obua and a number of other soccer players fled to Kenya, where he played for Luo Union.
In 1968, he was selected to represent East Africa in a game against visiting English club West Bromwich Albion.
On 30 November 2004, he announced that the executive board's term of office had expired; this was disputed by Obua's predecessor as FUFA president, Twaha Kakaire.
[9] A pressure group of Ugandan soccer fans then brought charges against Obua and FUFA's former secretary-general, alleging that they had embezzled funds while in office.
Obua was in Kenya on CECAFA business when the charges were laid and on his return to Kampala he was arrested for failing to appear in court.