Can social media predict crime?
Can someone's actions on social media ever be a guide to what they might be capable of doing in real life?
Months before the murder of teacher Ann Maguire, her killer Will Cornick had sent Facebook messages saying she deserved "more than death".
Stephen Kavanagh, the national policing lead on digital crime for the College of Policing, and Dr Elizabeth Yardley, a criminologist at Birmingham City University, discuss.
First broadcast on BBC Radio 4's Today programme on Saturday November 8 2014.
08 Nov 2014