Speaking on Sky News, the Master of the New College of the Humanities in London and a staunch Remainer, reiterated his view last year's June referendum was merely advisory and there was “no mandate” for the UK to leave the EU without Parliament discussing it openly first.
A verdict is due this week at the Supreme Court over whether or not Theresa May is required to seek Parliamentary approval before activating Article 50.
All Out Politics presenter Adam Boulton suggested the renowned philosopher was in a sense “arguing with the referee after the game” and that the referendum had been lost.
Professor Grayling said: “No, not at all. It’s looking at the intention that lay behind the referendum bill.
"Noticing very, very clearly that the intention of the bill was to provide a proper opportunity for Parliament to debate the outcome of the referendum and that hasn’t happened, which is pretty extraordinary. Parliament has been sidelined.”
Professor Grayling calls for 'direct action' if Parliament isn't given an open debate
There is no mandate and I think no majority in this country for leaving the EU
A C Grayling
Ministers are preparing for Tuesday’s Supreme Court judgement on whether Mrs May needs Parliamentary approval to start Brexit.
The court is expected to uphold a High Court ruling last year in favour of campaigners, led by investment manager Gina Miller, who say the Prime Minister must ask MPs and peers before triggering Article 50 of the Lisbon Treaty.
Four drafts of law have been prepared by the Government to try to cover any eventuality when the 11 judges deliver their verdict.
Theresa May and ministers are waiting for Tuesday's Supreme Court judgement
Professor Grayling added: “We’re told by Mrs May that she doesn’t want Parliament to debate this now but maybe several years down the line there can be a debate on the terms of the deal.
“But even if Parliament rejected the deal, she would still take the country out of the European Union. This is really very extraordinary.”
Asked whether his preference would be to have another referendum, he said: “I think there are a number of different options.
“First preference would be for Parliament to have a full debate on this. An un-whipped vote at the end of the debate and for all those MPs, the great majority of whom in the House of Commons, an even larger majority in the House of Lords, who were for Remain, presumably on the grounds of considered and informed judgement about the benefits of EU membership, would vote in line with their convictions.
“If that were to be the case, then the Brexit process would stop.”
He added if this didn’t happen he would want direct action, with the 67-year-old recently suggesting a general strike could be called.
Mr Trump spoke out against protestors
Mr Trump spoke out against millions of people who went on Women’s Marches in protest of him becoming America’s 45th President.
In a tweet, he asked why protestors hadn’t voted, before tracking back and describing peaceful protests as a “hallmark of democracy”.
Professor Grayling said similar action in the UK could have a powerful impact.
He said: “It’s very, very important that people should realise that that kind of expression of opinion and that kind of activism, that kind of engagement in the process, could have a major effect.”
Who is Gina Miller?
Thu, November 3, 2016
Gina Miller is leading the challenge that has blocked Theresa May triggering Article 50 without the consent of Parliament, take a look back at Miller's background.
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Gina Miller has won the case to block Theresa May from Article 50
He went on to argue it was not the will of the people to leave the EU.
He said: “I really do think that that phrase ‘the will of the people’, we’re talking about 37 per cent of the electorate that was enfranchised, 26 per cent of the population.
“This is not the people, this is a dishonest phrase ‘the will of the people’, ‘the British people have spoken’, this is something that the Brexiteers always quote in order to try to hustle us past the point of no return.
“There is no mandate and I think no majority in this country for leaving the EU and that is the point of fighting against it.”