The choir’s last official performance was in 2007, around the time of the death of its founder, Walter J. Turnbull. But no one ever announced that it was gone. Board members and alumni had hoped to revive it, but they acknowledged last week that they had not had any success.

For a famous organization that politicians had vowed would outlive its founder, it had a quiet end. Many of the choir’s materials, like copies of handwritten scores and its trademark burgundy blazers, now sit in black garbage bags and open boxes in the church’s damp dirt-floor basement, amid overturned tables and sacks of plaster of Paris.

Led by Dr. Turnbull, who started the group in 1968, the choir sang at the White House for nearly every president since Lyndon B. Johnson, and it was awarded the National Medal of Arts by Bill Clinton. But it did not survive long enough to perform for the country’s first black president.

The choir’s demise as a functional organization was a result of many factors, but everyone agrees it was set in motion by a single episode: an accusation by a 14-year-old boy in 2001 that a counselor on the choir’s staff had sexually abused him. The counselor eventually was sentenced to two years in prison.

The accusation and the scandal that followed  Dr. Turnbull did not report the claim to the authorities and allowed the counselor to continue working with children  set off a chain of events that led the city to oust the choir in 2006 from the Choir Academy of Harlem, the school building that had been its home. That, in turn, deepened the choir’s already serious financial problems.