He then joined the counterintelligence section of Field Marshal Douglas Haig, the British commander. In late 1917, he reported to high British leadership that Haig's intelligence chief Brigadier John Charteris was fudging intelligence estimates, which soon led to Charteris' removal. This whistle-blowing was apparently done very discreetly. Menzies was promoted to brevet major before the end of the war.C: The Secret Life of Sir Stewart Graham Menzies, Spymaster to Winston Churchill, by Anthony Cave Brown, 1987, Macmillan, New York, , pp. 82–98
