The former foreign secretary was “empty-chaired” by Channel 4, who left a lectern free for him alongside his five rivals to succeed Theresa May, while presenter Krishnan Guru-Murthy said he was welcome to join them at any point during the 90-minute broadcast.
Twenty-five minutes into the debate, Jeremy Hunt turned his fire on the absent frontrunner, asking: “Where is Boris? If his team won’t allow him out to debate with five pretty friendly colleagues, how is he going to fare with 27 EU countries? He should be here.”
Other contenders took barely veiled swipes at Mr Johnson, with Rory Stewart, the international development secretary, saying the party needed to turn away from “great leader macho posturing” and the politics of “the great ‘Me’”. He pointedly noted that he hoped the next prime minister would be one of the five contenders taking part in the debate.
All the candidates, with the exception of Brexit hardliner Dominic Raab, denounced the option of asking the Queen to suspend parliament in order to stop MPs from blocking a no-deal Brexit, an option not ruled out by Mr Johnson.
Amber Rudd, the work and pensions secretary, who is backing Mr Hunt for the leadership, warned earlier in the day that enough Tory MPs were prepared to back a no-confidence vote to bring down a prime minister who tried to force a no-deal withdrawal from the EU.
Mr Hunt said that shutting down parliament would be “a profound mistake”, while Mr Stewart said that the move, known as “prorogation”, would be “undemocratic and deeply disturbing and would strike at the heart of our constitution”.
Rejecting prorogation, Sajid Javid, the home secretary, said: “You don’t deliver on democracy by trashing democracy. We are not selecting a dictator of our country, we are selecting a prime minister for one of the proudest parliamentary democracies in the world.”
And Michael Gove, the environment secretary, insisted that there must be a vote in the Commons on the final form of the UK’s EU withdrawal, saying: “We can’t leave unless parliament votes for it.”
But former Brexit secretary Mr Raab insisted that prorogation must be kept on the table to ensure that the EU takes seriously Britain’s determination to leave on the latest Brexit deadline date of 31 October.
Mr Raab presented himself as “the only candidate committed to leaving by the end of October, come what may” and said the key issue in the leadership contest was regaining the “trust” of voters frustrated by the failure to deliver on the result of the 2016 referendum.
Mr Hunt said he would not rule out a no-deal Brexit as a last resort, but warned it risked a “potentially catastrophic rift” with the UK’s European neighbours. Mr Javid said it would be “a complete nonsense” to take no-deal off the table, saying that the “number one mistake” of Ms May’s Brexit strategy had been the failure to prepare properly for withdrawal without an agreement.
Only Mr Stewart set his face firmly against no-deal, saying the other contenders were effectively saying they would threaten the EU that if it did not give them the deal they want, they would take steps which they themselves had said would be deeply damaging to the UK economy.
He won applause from the audience, made up of floating voters who said there was a possibility they could vote Tory, as he said: “The problem is that there is a competition of machismo, with everybody saying ‘I’m tougher’. They are not going to get a different deal from Europe.”
Mr Gove said that he would be able to improve on the deal agreed by Ms May with Brussels last November because of his personal commitment to the Brexit cause and his record of defeating “impossible odds” in his education, justice and environment briefs.
Recalling the collapse of his father’s fish processing company, which he blames on the EU, Mr Gove said: “For me it’s personal because of what happened to my family and my father, so I’m going to keep fighting until we leave the EU and take back control of our money, our laws and our borders.”
Mr Gove said that he was the candidate who Jeremy Corbyn would most fear facing in the House of Commons.
And he said there was “nothing more important” for the 160,000 Tory members who will choose the new leader from a shortlist of two selected by the party’s MPs than keeping the Labour leader out of Downing Street.
Mr Hunt said that a Corbyn government would “destroy the dreams of all our children” to own their own homes and start businesses. He said the Conservative Party and the country were “in peril” from Mr Corbyn’s plan for “a Venezuelan or Cuban Britain”.
And all the contenders agreed that the only way to see off the challenge of Nigel Farage’s Brexit Party was to deliver Brexit. Only Mr Stewart suggested he would be ready to work with Mr Farage, having appeared on his LBC radio talk show earlier in the day.
Mr Gove dismissed Mr Farage’s demands for a role in the negotiation process, saying: “Brexit isn’t about one politician’s ego trip. It’s about bringing this country together.”
The environment secretary rejected the charge of hypocrisy over his cocaine use as a young journalist. And he was defended by Mr Hunt, who said that focusing on individuals’ behaviour 25 years ago was “trivialising” the important issues at stake.
Mr Stewart said that in his campaign visits around the country he had detected “a huge yearning for the centre ground in British politics” and said he was “not ashamed” of the fact that he was the preferred candidate of Liberal Democrat and Labour supporters whose votes the Tories need to win over.
The six leadership candidates now face a second round of voting on Tuesday, when they need to garner the votes of at least 33 of the 313 Tory MPs and avoid coming last in order to stay in the contest. Survivors will face the cameras for a second TV debate that evening on the BBC, which Mr Johnson has said he will attend.
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