According to the New York Times, the statement read: "Opera houses are often pressed for rehearsal and preparation time, and Ms. Norman is forced to accept these circumstances and yet still remain true to her high regard for the responsibility that she attaches to her craft and indeed the responsibility of helping to tell this particular story in its fullness."

The famous soprano was to sing the supporting role of Cilla in the premiere of Richard Danielpour and Toni Morrison's opera at Michigan Opera Theatre next month. She has been replaced by the up-and-coming singer Angela Brown. Initally, MOT said that she had withdrawn for "personal reasons."

Margaret Garner is based on a true story of a runaway slave who sacrifices her children rather than see them returned to slavery—a story that also inspired Morrison's novel Beloved.

The opera was co-commisioned by DOT, Cincinnati Opera, and the Opera Company of Philadelphia. The world-premiere production, which will be presented by all three companies, features mezzo-soprano Denyce Graves in the title role as well as baritones Rodney Gilfrey and Gregg Baker. Stefan Lano is the conductor; Kenny Leon directs.