 He broke with the Conservatives in the 1890s, running and being re-elected as an Independent Member of Parliament (MP) in the 1891 election.He appears to have been associated with the Equal Rights Party which ran in that election but did not run as their candidate.It was his firm, Boulton & McCarthy in Barrie, that was the first incarnation of what is now Canada's largest law firm, McCarthy Tétrault.