Commander Dave Johnston is a senior English police officer, currently the head of the Homicide and Serious Crime Command for the Metropolitan Police. Johnston is the Metropolitan Police's head of homicide and serious crime, in which capacity he led the Damilola Taylor and the Torso in the Thames Investigations. He also advised the Suffolk police on the Ipswich Murders. Prior to joining the police force he served in the Royal Engineers from 1974 to 1979, having joined the army as a boy soldier in 1972 and trained at the Army Apprentices College in Chepstow. After joining the police, he obtained an MSc in public management and a postgraduate qualification in criminology from Fitzwilliam College, Cambridge.