He became a prominent public figure through his political lectures, in which he argued for secularism and an immediate separation of New South Wales from England.
In February 1885 he played a prominent role in a meeting held to discuss British government policy towards the Pacific Islands, and shortly afterwards he was involved in opposing the deployment of New South Wales troops to the Sudan.
[4] Some time after 1894, Walker visited New Zealand, where he taught elocution, promoted temperance, lectured on various subjects, and wrote for the press.
[2] It was while editor for the Sunday Times that he is believed to have written the article "Corruption by Contract" condemning C. Y. O'Connor and the Golden Pipeline scheme.
On 27 October 1905, Walker was elected to the Western Australian Legislative Assembly seat of Kanowna on a Labor ticket.
[2] When the Labor party won government under John Scaddan on 7 October 1911, Walker was appointed Minister for Justice and Education, and Attorney General.