Natalie Maines, lead singer for the Dixie Chicks, is being sued for defamation by the stepfather of a murdered child. Terry Hobbs says Maines alleged that he was involved in the killings of three young boys, including his stepson, in West Memphis, Ark., in 1993, although three other men were arrested and imprisoned. Maines took part in a rally in Little Rock, Ark., last year, and wrote extensively on the Dixie Chicks Web site about new evidence in the case. All of the band members are named in the lawsuit, but Hobbs focuses mostly on Maines. The same evidence that Maines presented in her writings is also noted in papers by lawyers seeking to overturn the original conviction of the men, sometimes referred to as the West Memphis Three.