 He served as a member of the Indian Defence Council in 1941–42 and as the Vice-Chancellor of Madras University from 1940 to 1942.On 2 July 1942, the Viceroy of India, Lord Linlithgow, expanded his Executive Council to nineteen members, bringing in Usman, Sir C. P. Ramaswami Iyer, B. R. Ambedkar, Sir Jogendra Singh, and Sir J. P. Srivastava.This took the number of Indian members of the Council to fourteen, with five Europeans.