By 1921, aged 27, he had become a senior figure in Palestinian politics. His uncle, Musa Kazim, an Ottoman administrator and under the British, briefly, Mayor of Jerusalem, was chairman of the Executive Committee of the Palestine Arab Congress formed by the Muslim-Christian Associations, which had been established following the arrival of the British. Jamal was appointed Secretary to the Executive. Jamal and Musa Kazim were at this time considered the foremost representatives of the Palestinian Arab community. Following the disturbances of 1921, also known as the Jaffa Riots, Jamal had a meeting with the High Commissioner, Sir Herbert Samuel, and issued a statement calling for calm.