The Devil's Advocate by Fred M. White

Ned Hammer gave a strange sort of a gasp as be turned his sightless eyes in Philp's direction. He was not an emotional man, he had had many years' training in a hard military school, and his crowning misfortune had stilled him into the semblance of a mere machine that works according to rule. Here was a man, Philp decided, who could and would have baffled any counsel, however astute, if he only made up his mind not to speak. He must act accordingly.

"What's that you said, sir?" Hammer asked, very quietly.