Winston Churchill speaks at a munitions factory in 1916.

In London, a British Board of Trade panel concludes its probe of the Lusitania's loss. The head of the inquiry, Lord Mersey, will later complain, "The Lusitania case was a damned, dirty business." In closed door hearings, the British Admiralty - spearheaded by Churchill - initially sought to lay the blame for the disaster on Captain Turner, but after Mersey and the lead prosecutor discovered that naval officials had falsified evidence, Mersey halted proceedings and immediately asked the three-man panel for its sealed-envelope verdict on the captain.

In Mersey's final report, the panel finds Turner not guilty of negligence or incompetence, but notes that the Lusitania might possibly have been saved had he followed the Admiralty's anti-submarine tactics more carefully. The final report also reveals the existence of the 5,000 artillery casings in the Lusitania's hold, but implicitly dismisses the German assertion that exploding ammunition caused the second explosion and led to the great death toll. Instead, the report embraces the British Admiralty's theory that the Lusitania was struck by a second torpedo, a scenario that is contradicted by the U-20's. Ultimately, the panel places the blame for the Lusitania disaster solely on the Germans.