 He supported the White Australia policy but disagreed with key elements, and was a leader in opposition to the dictation test, by which a potential immigrant was required to pass a test in any European language before their application was accepted.He also campaigned for a transcontinental railway and for a capital city to be located on federal territory.Attempts to guide financial reform through the parliament as a backbench senator led to frustration, and Walker retired due to ill health in 1913 with his legislation unpassed.