William Ossington

In the novel Murder is Easy, Sir William Ossington (nicknamed Billy Bones) is an assistant commissioner at Scotland Yard and a friend of Luke Fitzwilliam.

Late in the story, Luke visits "Billy Bones" to seek his help on his investigation into the mysterious deaths in the village of Wychwood under Ashe. Luke lays out his findings and conclusions to Sir William. In turn, Sir William is able to contribute one more piece to the puzzle by summoning his subordinate Bonner. Bonner was the investigating officer in the death of Lavinia Pinkerton. According to Bonner, witnesses at the scene of the car accident described the car involved as a Rolls. Moreover a witness at the scene of the car accident had told someone else the car number was FZX 4498, a number which matched the car belonging to Lord Whitfield. Although the driver of the car said he was somewhere else, Luke was nonetheless certain that Lord Whitfield's car must have been the offending vehicle.

It is not stated explicitly, but it is likely that it was Sir William who sent Superintendent Battle to the village to wrap up the case.