Book excerpt: Since the early 1990s, unexplained infant death has been reformulated as a criminal justice problem within many western societies. This shift has produced wrongful convictions in more than one jurisdiction. This book uses a detailed case study of the murder trial and appeals of Kathleen Folbigg to examine the pragmatics of proof beyond a reasonable doubt. It explores how legal process, medical knowledge and expectations of motherhood work together when a mother is charged with killing infants who have died in mysterious circumstances. The author argues that Folbigg, who remains in prison, was wrongly convicted. The book also employs Folbigg's trial and appeals to consider what lessons courts have learned from prior wrongful convictions, such as those of Sally Clark and Angela Cannings. The author's research demonstrates that the Folbigg court was misled about the state of medical knowledge regarding infant death, and that the case proceeded on the incorrect assumption that behavioural and scientific evidence provided independent proofs of guilt. Individual chapters critically assess the relationships between medical research and expert testimony; the operation of unexamined cultural assumptions about good mothering; and the manner in which contested cases are reported by the press as overwhelming.