Prosecutors say Michele Graham shot 23-year-old Olivia Brown outside the Lincoln Houses in East Harlem on July 23.
Manhattan District Attorney Cyrus Vance Jr. said Thursday that Graham has been indicted on charges of second-degree murder and criminal possession of a weapon.
Democratic candidates Bill de Blasio, John Liu, Christine Quinn, Bill Thompson and Anthony Weiner had a sleepover with different families in the Lincoln Houses a few days before the shooting. They were there to examine mold, holes in walls and other issues.
A lawyer for Graham did not immediately return a call seeking comment.