The bad news for prime minister Boris Johnson is that he has a big trust problem with the voters: the good news is that it may not matter in Britain’s upcoming election.

“I don’t believe a word that comes out of his mouth,” said Jenny from Derbyshire, before cheerfully confirming that she would be voting for him.

Mr Johnson on Tuesday went head to head with Jeremy Corbyn in the first television debate of the 2019 election, with both men having an opportunity to look the voters in the eye and ask them to put the country’s future in their hands.

But while Mr Johnson and Mr Corbyn were preparing for the debate in Media City, Salford, down the road at the Christmas market in Albert Square, Manchester, voters were making it clear that trust may not be the first thing on their mind at the ballot box.

“I don’t trust any politician,” said Ryan Dior, a script writer. The polls back that up: any trust the voters had in Britain’s political class took a battering during the 2009 expenses scandal and the situation has barely improved since then.

An Ipsos/Mori “veracity index” survey in 2018 found that politicians were among the least trusted professionals in Britain, with only advertising executives deemed to be less reliable sources of the truth.

For Mr Johnson, the public’s low expectations may work to his advantage: the prime minister has twice been sacked for lying — first as a journalist for making up a quote, and then as a Conservative frontbencher for lying about an extramarital affair.

On the campaign trail, Mr Johnson has also been forced to explain why, in spite of saying he would “die in a ditch” if Britain had not left the EU by October 31, he was still standing and running for prime minister.

His character has been put under the spotlight, whether over the nature of his relationship with Jennifer Arcuri, the US tech entrepreneur, or his inability to answer direct questions about how many children he has.

But in Albert Square, amid the glühwein and wurst stalls, it is clear that Mr Johnson’s chequered past has often been baked into the candidate’s price and, crucially, the voters seem to like him more than Mr Corbyn.

Alex Clare, a 31-year-old local council worker who voted Labour in 2017, said: “I believe he’s going to make the right decisions for the country. Whatever he has done wrong in the past should be put aside. This is about getting things done now.”

The voters’ tolerance of Mr Johnson’s chequered past is striking. “I like him. My head says ‘no’ but my heart says ’yes’,” says Victoria, an assistant buyer, over a glass of mulled wine.

Whatever the questions about his character, Leave voters believe Mr Johnson will deliver Brexit, the key issue for voters in this election. A YouGov poll this month found that 68 per cent of Leave voters in 2016 believed Mr Johnson would see Brexit through.

Alex Clare is backing Boris Johnson © Andy Bounds/FT

Political opinion can swing wildly in Britain — as the 2017 election campaign showed — but this snapshot of voters in Manchester suggests that Mr Corbyn will need to put in the performance of his life in TV debates and on the campaign trail to turn round the contest.

Polling suggests that voters like the Labour leader less, trust him less with big decisions and see him as weaker than his Conservative rival.

Mr Corbyn’s problem with voters is less about his personal character — although a number of those in Albert Square mentioned his failure to deal with anti-Semitism in the Labour party — but on whether he can deliver on his promises.

“I don’t believe him, I don’t trust him,” said Mark Evans, a retired prison officer from Warrington. Mr Evans, a former Labour voter, added: “I think he would bankrupt the country. I don’t think we can afford the policies he is coming up with.”

Kathleen Stretton, 72, a retired school secretary from Bury, said: “They [Labour] are always talking about what they are giving money to but they never tell you where it is coming from.”

Kathleen and David Stretton say they will not vote for the first time in their lives © Andy Bounds/FT

She and her husband David Stretton, a former bus driver, are both Leave supporters and have decided not to vote for the first time ever. Mr Stretton, 74, has voted Labour his entire life, “Those MPs can argue until the cows come home and still not get us out of Europe. I would not vote for any of them.”

Michael Thomlinson stops his wheelchair briefly when asked who he is voting for. “Not Corbyn. He wants to get rid of Trident [Britain’s nuclear deterrent], he does not know what he wants to do about Brexit. How can you trust a bloke like that?”

Even among students, who helped power Labour to a better than expected performance in 2017, Mr Corbyn’s appeal may be waning. “Boris Johnson is a joke . . . but Corbyn would be bad for the country’s future,” said Dom Wills, a 20-year-old music student.

Gideon Skinner, research director at Ipsos Mori, says that his company’s polling in September found that 37 per cent of people thought Mr Corbyn was more honest than most politicians (compared with 27 per cent for Mr Johnson).

However, when the pollster in 2014 asked people what were the most important attributes they wanted to see in a prime minister, trustworthiness emerged as somewhat overrated.

Being more honest than most came in behind measures such as understanding Britain’s problems, being capable and good in a crisis, and having sound judgment.

Whatever the verdict of viewers watching the leaders go head to head on Tuesday, whether they believed a word each of the candidates may have been only part of their calculation.

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