 As a lawyer in the Maritimes, McKelvey appeared several times in cases involving shipping issues, such as an inquiry under the "Canadian Shipping Act" into the 1957 collision between the Saint John harbour boat and the freighter "Fort Avalon".He also represented the Canadian Coast Guard before a Royal Commission inquiring into the grounding of an oil tanker, "Arrow", in Chedabucto Bay, Nova Scotia, in 1970.The grounding resulted in the spill of 108,000 barrels of oil, leading to questions about the way the Coast Guard had responded to the environmental hazard.