Todd, Charles. Inspector Ian Rutledge novels

In 1914, Ian Rutledge left a brilliant career at Scotland Yard to fight in the Great War. Now, in 1919, he is back, burdened with a heavy secret: he is still suffering from shell shock. With him almost constantly is the cynical, taunting voice of the young Scots soldier he was forced to have executed on the battlefield for refusing to fight. In a desperate gamble to salvage his sanity, Rutledge takes up his duties at Scotland Yard. But a colleague, jealous of Rutledge's prewar successes, has learned his secret and maneuvers to have him assigned to a case that promises to spell disaster no matter what the outcome. In a Warwickshire village, a popular retired military officer has been murdered, and the chief suspect is, unhappily for the Inspector, a much-decorated war hero and a friend of the Prince of Wales