Additionally he completed a habilitation in Roman Law in 1913.

[3] From 1914, Steiner was active as Privatdozent at the University of Zurich and ultimately from 1918 to 1920 as senior lecturer.

Between 1918 and 1922, Steiner held his first public office, as municipal councillor of Schwyz.

He served as a member of the Cantonal Council of Schwyz from 1920 to 1925 for the Catholic Conservative Party.

His daughter Elisabeth Blunschy was the first woman elected president of the National Council, his son-in-law Alfred Blunschy, also served on the Cantonal Council.