Ashley John-Baptiste looks at the 2023 stabbing of a 16-year-old girl in Warrington, and how a forensic analyst was tasked with examining the exhibits recovered from the homes of both suspects, including a bloodstained knife, clothing and footwear, helping to connect them both to the attack. There's also a look at the Boxing Day murder of PC Ian Broadhurst, who was shot when he and colleagues tried to stop a suspected car thief, and how a forensic speech expert matched a voice on police dashcam to his killer