Career
He represented Inverness County in the Nova Scotia House of Assembly from 1874 to 1878 and from 1886 to 1894 as a Liberal member. He was born in Whycocomagh, Nova Scotia, the son of Laughlin McKinnon, a Scottish immigrant, and Annie McLean. He was educated in Halifax.
McKinnon married Harriet McQueen.
McKinnon ran for reelection unsuccessfully in 1878 and 1882.