[2] In 1892, Walker ran for on the Democratic ticket for Missouri Attorney General and was elected with 49.5% of the vote.

During this time he was counsel of the St. Louis Merchants' Exchange,[4] in 1907 he was elected President of the Missouri Bar Association,[4] and he traveled and spoke at different events and universities.

One such event was an address to the Current Topics Club in St. Louis, at which Walker criticized then president Theodore Roosevelt, for inviting Booker T. Washington to the White House.

"[12] The same year, Walker spoke at the Old Settler's Association of Morgan County, his address was transcribed and filed in the Library of Congress.

[4][5] As a justice, Walker was "known on the bench for his liberal views and frequent opinions dissenting from the majority".