Why have British attitudes towards homosexuality changed so far and so fast? Jo Fidgen examines this test case for how public opinion can move.

Why have British attitudes towards homosexuality changed so far and so fast? Less than 50 years ago, sex between men was a criminal act. Now they can marry. It's not just the law that has changed: we have. Surveys suggest that public opinion about homosexuality has undergone a dramatic shift over the same period. Jo Fidgen asks what drives this kind of change in collective attitudes.

Producer: Chloe Hadjimatheou.