In 1948 Boni was elected to the French National Assembly on behalf of the Voltaic Union (UV), and was re-elected in 1951 running on the Economic and Social Action in the Interests of Upper Volta list, although he remained a UV member.

In 1955 Boni founded the African Popular Movement (MPA) after a split from the UV.

[2] From December 1957 to February 1958 Boni served as President of the Territorial Assembly.

[3] In 1959 he founded a new party, the Republican Party for Liberty, in opposition to the attempts to make Upper Volta a one-party state under the Voltaic Democratic Union.

[1] In 1962, Boni wrote a novel, Le Crépuscule des temps anciens (The Twilight of the Bygone Days), which explored the precolonial existence of the Bwa people and the Volta-Bani War.