He was a Progressive Conservative member of the Legislative Assembly of Manitoba from 1958 to 1969, and served as a cabinet minister in the governments of Dufferin Roblin and Walter Weir.
Carroll won a landslide victory over his two opponents; the third place candidate was future Premier of Manitoba Howard Pawley, representing the CCF.
The Progressive Conservatives formed a minority government after this election, and Carroll was appointed Minister of Public Utilities on June 30, 1958.
Carroll was retained in the Public Utilities portfolio, and also served as Provincial Secretary from October 1 to December 21, 1959.
He announced that he would create the position of a provincial ombudsman in 1969, although the Weir government was voted out of office before he could follow through on this pledge.