FORT WORTH, Texas — An Army psychiatrist accused of killing 13 people during an attack on his Texas post will likely plead not guilty to the charges against him and may use an insanity defense at his military trial, his attorney said Monday. John Galligan, the civilian attorney for Maj. Nidal Hasan, said he is considering an insanity defense among other options, but that it's too early to determine his defense strategy. "Based on the evidence thus far, his mental status must be raised," Galligan told The Associated Press by phone from his office near Fort Hood, about 130 miles southwest of Dallas.