Matthew Williams is Professor of Criminology at Cardiff University, and is widely regarded as one of the world's foremost experts in hate crime. He advises the Home Office, Ministry of Justice and US Department of Justice among others; regularly appears in the media and he has documentary crews knocking at his door. He runs the 'HateLab' which has a GBP1m grant to assess the impact of national events on levels of hate crime and speech. @MattLWilliams