After retiring from naval service, Mifflin entered politics and was elected to the Canadian House of Commons in the 1988 Canadian election as the Liberal MP for the Newfoundland and Labrador riding of Bonavista-Trinity-Conception.
Mifflin entered politics. Mifflin was elected to the Canadian House of Commons in the 1988 Canadian election as the Liberal MP for the Newfoundland and Labrador riding of Bonavista-Trinity-Conception. Mifflin was retiring from naval service.