He served in the Legislative Assembly of Alberta from 1967 to 1975 as a member of the Social Credit caucus in both government and opposition.
Drain first ran for a seat to the Alberta Legislature in the 1967 general election.
He defeated incumbent MLA Garth Turcott to pick up the Pincher Creek-Crowsnest electoral district for the governing Social Credit party.
[3] In the 1975 general election, his share of the popular vote fell sharply and he was defeated by Progressive Conservative candidate Fred Bradley.
[4] Charles married Mary Michalski and together they had four children, Douglas, Clair, Edmund, and James.