He was the founder of the Oromo Federalist Democratic Movement (OFDM), one of Ethiopia's largest opposition parties.

[1] In 1967, Demeksa was appointed vice-minister of Finance before representing his country at the board of the World Bank.

[2] Demeksa has been one of the most outspoken opponents of the late Meles Zenawi's government and the opposition leader most referred to by the international media.

His retirement from OFDM and his harsh criticism of Prime Minister Meles Zenawi and of the 2010 elections were a regular feature story on dozens of private Amharic and English newspapers in the country.

[4] At the end of 2008, Demeksa was named "Person of the Year" by Jimma Times, the online version of the defunct Afan Oromo private Yeroo newspaper.