Dr Rosalind Beck is a Doctor of Criminology and a Conservative Party member in South Wales.

When Jeremy Corbyn mouthed the words ‘stupid woman’ about Theresa May in the House of Commons yesterday, I waited, intrigued at the dilemma now facing him.

How would this conceited man be able to now mouth the word ‘sorry’? It is axiomatic that politics attracts narcissists, and a key trait of narcissism is a ferocious refusal to apologise for anything.

Little did I imagine, however, that he would have the front and the gall to deny that that is what he in fact said and instead claim that he had said ‘stupid people.’

If, like me, you have since practised mouthing the word ‘woman’ and ‘people’ in the mirror and compared how your lips contort very differently for each word, you will have seen the futility of this denial. I didn’t need a lipreading expert to confirm this (although four have, since).

I was also interested in how others would see what I thought of as something pretty outrageous, and so I mimed the two versions in front of my teenage children and asked them how they thought Jeremy Corbyn’s denial made him look; my daughter laughed and said it ‘makes him look dumb.’ My son said it ‘means he’s a liar.’

Of course, Corbyn has form. One only has to recall him being forced to ‘rough it’ on the floor of the ‘ram packed’ London to Newcastle train two years ago; only for a video to later emerge showing a large selection of available seats. A normal person would be aghast at being caught out in such a deceit.

Not Jeremy. He seems completely ignorant of the fact that, as Immanuel Kant stated, ‘By a lie a man throws away and, as it were, annihilates his dignity as a man.’

A member of his Shadow Cabinet at the time, the excellent Chris Bryant, clearly understood this when he said: ‘The biggest sin in politics is hypocrisy. I think a lot of people will feel led up the garden path by this.’

In my view Corbyn sunk to a new low yesterday, however, with the lip-readers now confirming that he told a brazen lie in front of Parliament and the whole country.

And, coincidentally, or not, on the same day he thought he could magically turn the word ‘woman’ into ‘people’, his colleague, Fiona Onasanya, was found guilty of lying multiple times about speeding and her lying has caused her to be accused of bringing the party into disrepute.

In addition, although the bare-faced lying appears to have taken precedence as the worst aspect of this, Corbyn’s latest faux pas also showed him, of course, to be a sexist. Jess Philips, the Labour MP, has said that in fact Labour politicians are the ‘absolute worst’ sexists; in her view, even worse than the ‘out and out sexists’ on the right. Many women would agree that it is preferable to deal with a simple, right-wing sexist than a left-wing one who camouflages their prejudice and hostility behind a mask of political correctness.

These incidents also remind us of the extent to which sexism in politics is condoned and is endemic. It was supremely ironic, for example, as Anna Soubry and Andrea Leadsom pointed out, that John Bercow was unable to chastise Corbyn for calling a senior Conservative politician a ‘stupid woman’, because he had been guilty of an identical offence against Leadsom. What kind of example are the leader of the Opposition and the Speaker of the House setting?

In contrast, racism is generally taken far more seriously. When a banana skin was thrown on the football pitch near the Arsenal player, Aubamayang, it was recognised that this was a racist attempt to undermine the player and the perpetrator was punished. All right-minded people understand that racists make black footballers’ lives miserable and may put them off pursuing their chosen career.

However, what is not accepted is that women are similarly undermined, and this too is a cancer in society. In the context of politics, it gives the message to other women that they too will have to tolerate this if they have the audacity to enter a ‘man’s world.’ Indeed, the Prime Minister has since said that comments such as that made by Corbyn are likely to put women off going into politics.

Unfortunately, progress seems slow or non-existent, despite there appearing to be a new impetus around this time last year, after the ‘me too’ movement. As I wrote at the time, if politicians display offensive attitudes towards women, how can we trust them to create a society free of discrimination?

I would now add that if they feel they can tell outright lies in Parliament, how can we trust anything they say? The short answer to both questions is: we can’t.