Background
Mewhirter was born in Sugar Grove, Illinois, United States of America, the son of Robert Mewhirter, and was educated in New Providence and at Drake University in Des Moines, Iowa.
Mewhirter was born in Sugar Grove, Illinois, United States of America, the son of Robert Mewhirter, and was educated in New Providence and at Drake University in Des Moines, Iowa.
He graduated in pharmacy and chemistry, and moved to Canada in 1906.
He became manager of the Gutta Percha and Rubber Company, Limited. in Winnipeg, and resided in Dugald. He was elected to the Manitoba legislature in the 1914 provincial election, defeating Liberal Thomas Glendenning Hamilton by 364 votes in the Elmwood constituency. In 1915, the Conservatives were forced to resign from office because a report commissioned by the Lieutenant Governor found the government guilty of corruption in the tendering of contracts for new legislative buildings.
Mewhirter was not a candidate.
He served in the Legislative Assembly of Manitoba from 1914 to 1915 as a member of the Conservative Party.