In 1991, Duplantier struck down an anti-abortion law passed by the Louisiana legislature over the veto of then Republican Governor Charles E. "Buddy" Roemer, III.
Duplantier and two other Louisiana Democrats, former State Treasurer Mary Evelyn Parker and former State Representative Risley C. Triche of Napoleonville in Assumption Parish, were interviewed for the 2001 book Welfare Racism: Playing the Race Card Against America's Poor.