Another development resulting from the 1929 riots was the growing animosity between the British Mandate Authority and the Yishuv. The inactivity of the British while Arab bands were attacking Jewish settlers strengthened Zionist anti-British forces. Following the riots, the British set up the Shaw Commission to determine the cause of the disturbances. The commission report, dated March 30, 1930, refrained from blaming either community but focused on Arab apprehensions about Jewish labor practices and land purchases. The commission's allegations were investigated by an agrarian expert, Sir John Hope Simpson, who concluded that about 30 percent of the Arab population was already landless and that the amount of land remaining in Arab hands would be insufficient to divide among their offspring.