He returned to Dáil Éireann at the 1987 general election and was re-elected again at the 1989 general election. In 1990, his Democratic Socialist Party merged with the Labour Party, and Kemmy was re-elected as a Labour Party TD at the 1992 general election and again at the 1997 general election. After the merger, Kemmy was elected vice-chairman of the Labour Party in 1991 and chairman in 1993. He was twice elected Mayor of Limerick, from 1991 to 1992 and again from 1995 to 1996.