Tackling knife crime has become an urgent political debate after Valdo Calocane admitted to the manslaughter of three people in Nottingham, denying murder on the grounds of diminished responsibility.
Last June he fatally stabbed Barnaby Webber and Grace O’Malley-Kumar, both 19-year-old students, and a school caretaker, Ian Coates, 65. On Thursday he was sentenced to indefinite detention in a high-security hospital.