CUMBERLAND, Md., May 7 — Ivan Frederick was distraught. His son, an Army reservist turned prison guard in Iraq, was under investigation earlier this year for mistreating prisoners, and photographs of the abuse were beginning to circulate among soldiers and military investigators. So the father went to his brother-in-law, William Lawson, who was afraid that reservists like his nephew would end up taking the fall for what he considered command lapses, Mr. Lawson recounted in an interview on Friday. He knew whom to turn to: David Hackworth, a retired colonel and a muckraker who was always willing to take on...
