Comedians have a habit of making people laugh – but they may also have a knack for getting away with murder.

As the latest series of Celebrity Traitors gets under way, a psychologist believes funnyman James Acaster could have an in-built advantage over his Traitor teammates because people are naturally more inclined to trust funny people.

Paddy Ross, an associate professor of psychology at Durham University, says celebrity versions of the hit BBC show operate very differently from the standard format because contestants already arrive with opinions about one another.

Unlike ordinary Traitors players, who begin as strangers, celebrity contestants may know one another professionally, personally or simply through their public personas.

That means psychological shortcuts and biases can play a huge role in deciding who is trusted and who comes under suspicion.

‘We are all prone to a cognitive bias known as the halo and the horn effect,’ Dr Ross wrote on The Conversation.

‘The halo effect occurs when we observe a positive trait in someone (like humour) and use it to assume that they have other positive traits in unrelated areas.

‘The comedians in the group have an advantage here.’

While TV presenter Maya Jama and actor Richard E Grant began the game as original Traitors, James Acaster was later recruited to join their ranks.

Of the three he is the only comedian, and is best known for his popular stand-up shows, surreal humour, hit podcast Off Menu and regular appearances on television panel shows.

Dr Ross explained that people often see humour as a sign that somebody is friendly and trustworthy, even though being funny has nothing to do with whether they are telling the truth.

This theory appeared to play out perfectly for comedian Alan Carr during the first celebrity series.

Despite later being revealed as a successful Traitor, many contestants struggled to believe the funnyman was capable of deceiving them because they already viewed him as a lovable national treasure.

‘His ability to make others laugh led to false assumptions about his trustworthiness through the halo effect,’ Dr Ross said.

‘Not even Carr’s giggling while trying to say he was a faithful was enough to make contestants change their minds about his role in the game.’

The psychologist also pointed to confirmation bias, which causes people to favour information that supports their existing beliefs while overlooking evidence that challenges them.

That can make it surprisingly difficult to spot a convincing liar once somebody has decided they are one of the Faithfuls.

On the flip side, celebrities who are perceived as abrasive or argumentative can suffer from what psychologists call the ‘horn effect’.

That bias can leave fellow contestants more willing to suspect them, regardless of whether they have done anything suspicious.

According to Dr Ross, celebrity status itself also creates another complication in the game.

Some contestants are considerably better known than others, potentially creating a hierarchy in which bigger stars carry more influence around the round table.

That could leave lesser-known celebrities reluctant to accuse household names, even when their instincts tell them something is wrong.

The expert also said that the likes of Hannah Fry could have an advantage over her fellow contestants – despite being at risk of being murdered this week.

‘If you’re a big fan of Hannah Fry and her factual science communication, it’s going to be difficult to let yourself believe she could be lying to you,’ he wrote.