Anybody who watched the European Championships of football this summer in France would have seen shocking scenes of violence between fans. The vast majority, if not all, were men. Men also commit more than 90% of murders across the world and are more likely to join a gang.

Why are men more violent than women? Caroline Bayley speaks to ex-football hooligan Cass Pennant about his experiences and motivation when violence became his way of life. Former British Army officer Jane Middleton explains the differences between men and women on the battlefield when she served in Afghanistan. And, Caroline also hears views from Sweden about how equal violence between men and women in relationships is.

(Photo: Group of football fans fighting in street. Credit: Carl Court/Getty Images)