Lillian Hellman in Are You Now or Have You Ever Been at the Promenade Theatre (1978), the title role in Candida at the Roundabout Theatre (1979), Tasha Blumberg in Isn't It Romantic? at the Playwrights Horizons (1983), Mrs. Thompson in Hunting Cockroaches at the Manhattan Theatre Club (1987), Rose Brill in The Rose Quartet at the Circle Repertory Theatre (1991), Aida Gianelli in Over the River and Through the Woods at the John Houseman Theatre (1998), Nelly Fell in The Torch-Bearers at the Greenwich House Theatre (2000), and as part of a rotating cast in Wit & Wisdom at the Arclight Theatre (2003). She won an Obie Award in 1991 for her portrayal of Eva Adler in The American Plan at the Manhattan Theatre Club. Copeland began working in television in the early 1950s as a guest actress on such shows as Suspense and The Web and on the live telecast of O'Neill's play The Iceman Cometh in 1960. She appeared on numerous soap operas. She portrayed Andrea Whiting (Joanne's daughter, Patti's malevolent former mother in-law) on Search for Tomorrow, twin sisters Maggie and Kay Logan on Love of Life, and roles on The Edge of Night, How to Survive a Marriage, and As the World Turns. She also portrayed Gwendolyn Lord Abbott on One Life to Live from 1978–1979, and later returned to the series to play Selma Hanen in 1995. Between 1993-1997 she portrayed the recurring character of Judge Rebecca Stein on Law & Order. Her other television credits include guest appearances on The Patty Duke Show, Chicago Hope, ER, All in the Family, and Naked City. Copeland made her first film appearance as Alice Marie in The Goddess (1958). Her film career was sporadic and her appearances have been almost exclusively in prominent secondary roles. Her film credits include Middle of the Night (1959), Roseland (1977), It's My Turn (1980), A Little Sex (1982), Happy New Year (1987), The Laser Man (1988), Her Alibi (1989), Jungle 2 Jungle (1997), The Peacemaker (1997), The Object of My Affection (1998), The Adventures of Sebastian Cole (1998), The Audrey Hepburn Story (2000), The Last Request (2006), and The Private Lives of Pippa Lee (2009). She also voiced Tanana in Disney's Brother Bear (2003). In December 2014, Copeland was invited, along with Broadway actor-singer Jamie Ross by The Noel Coward Society to lay flowers on the statue of Sir Noël Coward