He joined the Progressive Political League, a forerunner of the Victorian branch of the Labor Party, in 1892.

Prior to his election, Mathews also spent six years as the secretary of the South Melbourne branch of the Labor Party, remained involved in the Tailors' Union, and had made two unsuccessful candidacies for the City of South Melbourne council.

[1][2][3][4][5] Mathews contested the 1903 federal election, but was defeated by incumbent Protectionist Samuel Mauger.

[6] He was described The Courier-Mail upon his death as "a speaker of great force" and "an apt interjector" in the House.

In 1917, he was one of several political figures prosecuted under the War Precautions Act with having "made false statements of a kind likely to affect the judgment of the electors" in the referendum, but represented himself and was acquitted.