He served as president of the Ontario Public Service Employees Union Local 448 from 1986 to 1989, and was first vice-president of the Quinte Labour Council in 1988-89.
He also co-chaired the Quinte Environmental Resources Alliance, and was president of the Big Brothers/Big Sisters of Prince Edward, Ontario.
He ran for the Ontario legislature in the 1987 provincial election, finishing third in Prince Edward—Lennox against Liberal Keith MacDonald.
[1] The following year, in the 1988 federal election, he served as campaign manager for local New Democratic Party candidate Don Wilson.
[4] The NDP were defeated in the 1995 provincial election, and Johnson finished third against Progressive Conservative candidate Gary Fox in his bid for re-election.