In 1994, he was appointed by the
Ugandan military to be one of the delegates to the
Constituent Assembly that drafted the 1995 Ugandan Constitution. At age 29 years, Lieutenant Mayombo was the youngest member of the Constituent Assembly. He distinguished himself as an avid debater with a solid knowledge of the law and with a sense of humour. Following the ratification of the new constitution, Mayombo was appointed to represent the Ugandan military in the
Ugandan Parliament. He resigned that position on 30 January 2006, to take up an appointment as Permanent Secretary in the Ministry of Defence. He was appointed
President Museveni's
ADC where he displayed an insatiable sense of dedication and loyalty to the Movement system of government. One of the most enduring images was the ADC squatting after noticing that the shoelaces of the president were untied and promptly tying them. He received rapid promotion through the military ranks, quickly rising through Lieutenant,
Captain, Major,
Lieutenant Colonel to full
Colonel by 2004. By that time he was the Director of Military Intelligence. As Military Intelligence Director, he gained notoriety, where he was accused
torturing suspected rebels. During the same period, the Ugandan security organs were accused of the creation and maintenance of "safe houses", where arrested suspects were detained incommunicado beyond the 48-hour limit prescribed by law, without any charges being brought in court. It was under Brigadier Mayombo's reign as Director of Military Intelligence, that the People's Redemption Army under Colonel
Kiiza Besigye was first brought to the attention of Ugandans. Besigye was later to deny this and other accusations linking him to
Joseph Kony's
Lord's Resistance Army in
Northern Uganda. Brigadier Mayombo himself confronted Besigye over a radio talk show on KFM's
Hot Seat programme one evening. This was to reduce Besigye's popularity and maybe even affected his performance in the next presidential elections. In October 2005, Colonel Mayombo was promoted to brigadier and appointed Permanent Secretary to the Ministry of Defense. In November 2005, he was appointed Chairman of the board of directors at the
New Vision Group, the publishers of the Uganda government-owned newspaper
New Vision. ==Last days==