He represented Carleton in the Legislative Assembly of Ontario as a Conservative member from 1907 to 1919.
McElroy owned a general store, operated a flour mill and was a grain dealer.
McElroy was elected to the provincial assembly in a 1907 by-election held after the death of George Nelson Kidd.
He also served as a director for the Central Canada Exhibition.
This article about an Ontario Progressive Conservative Party MPP is a stub.