Will the US presidential debates change the course of the election?

On the 29th September the two US presidential candidates Donald Trump and Joe Biden will take part in the first of three 90-minute live televised debates ahead of the presidential election in November.

Tanya Beckett asks can the debates affect the outcome of the election?

(Composite image of Joe Biden (Credit: Jonathan Ernst/Reuters) and Donald Trump (Credit: John G Mabanglo/EPA)