The Littlehampton Libels tells the story of a poison-pen mystery that led to a miscarriage of justice in the years following the First World War. There would be four criminal trials before the real culprit was finally punished, with the case challenging the police and the prosecuting lawyers as much any capital crime.

When a leading Metropolitan Police detective was tasked with solving the case, he questioned the residents of the seaside town of Littlehampton about their neighbours' vocabularies, how often they wrote letters, what their handwriting was like, whether they...