After the defeat of the Ottoman Empire in the World War I, he was appointed the head of the Turkish courts-martial on the 18 April 1920.

Mustafa also sentenced Ebubekir Hazim (Tepeyran), the Minister of the Interior for aiding the Turkish nationalists.

Mustafa stated, Our compatriots have committed untold crimes by resorting to every conceivable form of despotism, organized deportation and massacre, burned feeding mothers doused with petrol alive, raped women and girls….

[3] His brother-in-law Izzet Bey was the former governor of the Van Vilayet and Minister of the Pious foundations under Tavfiq Pashas cabinet.

Mustafa's son was Abdul Aziz Yamulki, the chief plotter of coup d'état against the Bakir Sidqi government.