Conspiracy theories - Laurie Taylor explores their origin and evolution and considers the extent to which certain countries and people are more inclined to believe in them.

Conspiracy theories: Laurie Taylor talks to Thomas Konda, Professor of Political Science at SUNY, Plattsburgh, about the history and changing nature of conspiracy theories. Why have such wild theories overrun America? Also, Hugo Leal, Methods Fellow at the University of Cambridge discusses the most comprehensive examination of conspiracy theories ever conducted. About 11,500 people were surveyed in a study covered nine countries - the US, Britain (excluding Northern Ireland), Poland, Italy, France, Germany, Portugal, Sweden and Hungary. The research found that Trump and Brexit voters were more likely to believe in conspiracy theories than others.

Producer: Jayne Egerton