'I've got to know the man I killed'
Jacob Dunne killed James Hodgkinson with one unprovoked punch outside a pub.
Nine years later, Mr Dunne and his victim’s mother, Joan Scourfield, have become friends and she says she has forgiven him.
The pair now visit schools and prisons together to campaign against violence.
Mr Dunne, 28, from Nottingham, has been explaining how he has transformed his life through restorative justice in a new BBC podcast, The Punch.
Video by Jeremy Ball and Alex Thorp