King was a Special Agent in the United States Customs Service's New York office from 1968 to 1985, acting as a lead agent for undercover operations regarding Middle Eastern and Irish groups.[2] From 1985 to 2003 he was Supervisory Special Agent in the Strategic Investigations Division in the United States Customs Service's New York office. In this capacity, and due to his specialist knowledge, he was a member of the White House Legal Task Force on the Iran-Contra affair,[2] and in 1992 briefly assigned to the House October Surprise Task Force.[3]
King's undercover work included a role in a 1980 case involving arms smuggling to South Africa,[4] a role in the 1984 case against Cyrus Hashemi and his brothers,[5] and playing what he described as a "corrupt former C.I.A.-type" in a 1986 arms deal which became known as the Brokers of Death arms case.[1][6] Later he played an Irish arms dealer named Joe Kennedy, foiling a 1993 plot to smuggle zirconium to Iraq.[1]