Claudette Colvin, a civil rights pioneer who refused to give up her bus seat in Montgomery in 1955 at age 15, has died at 86. Her act of defiance preceded Rosa Parks' more famous protest and contributed to the Browder v. Gayle lawsuit that ended bus segregation. Despite her early activism, civil rights leaders initially favored Parks due to social and strategic considerations. Colvin later became a plaintiff in the lawsuit that led to the Supreme Court's 1956 decision banning segregation on public transit.