Davidson was a foundation member of the Australian Workers' Union and helped to form a local branch of the Amalgamated Miners' Association in Cobar.

He also served as an alderman on the Cobar Municipal Council from 1913 to 1918, where he worked to promote railway extension.

[1] In 1918 Davidson was elected as a Labor Party member for Cobar in the New South Wales Legislative Assembly.

With the introduction of proportional representation in 1920, the seat of Cobar was absorbed into Sturt and he was elected as one of its members.

From November 1930 to May 1932 Davidson served as Secretary for Public Works in the Third Lang Ministry.