Peter Joseph Lang was born in Kitchener, Ontario on November 19, 1950.

During his career, Peter worked as a coroner, physician, and psychiatrist.

He was elected as a Member of Parliament serving Ontario's Kitchener riding on February 18, 1980. He was a member of the Liberal Party of Canada.

He served as a Member of Parliament for four years until he lost his seat in the elections to John Reimer of the Progressive Conservative party in September 1984.