I would not have thought it possible still to be shocked by details of antisemitism in the Labour Party, but last night’s Panorama documentary left me stunned. The documentary showed how people at the top of the Labour Party have covered up, minimised and excused anti-Jewish racism. And it was heart-breaking to see how decent members of staff – people who joined and worked for the Labour Party to fight for a fairer society – had been driven out, made ill and even contemplated suicide.

How much worse can this scandal get before the Shadow Cabinet and Labour MPs finally say enough is enough?

Over the past few years we’ve seen Ken Livingstone’s bizarre ravings about Adolf Hitler and senior members legitimising the myth that Jews were the chief financiers of the slave trade. Jewish MPs – particularly women – have been subjected to the most horrendous abuse and terrible, violent threats, even being told they don’t have human blood.

Labour members have even been arrested on suspicion of racial hatred and the party now faces a full official inquiry for racism by the Equality and Human Rights Commission. And let us not forget that this crisis was triggered by the shocking discovery that Corbyn himself had defended a grotesque racist caricature on a mural in East London.

Panorama’s investigation revealed a huge increase in anti-Semitism complaints since Jeremy Corbyn became leader in 2015 and major disputes in the party about what constituted anti-Semitism.

The programme found evidence of interference in the complaints process by Corbyn’s inner circle, even showing complaints were directly processed by his own office. It even revealed that the General Secretary herself had been involved in a discussion about interference with the National Constitution Committee, the supposedly independent body that is meant to have the final say over expulsions. One former official says the suggestion Corbyn make a speech about Israel’s right to exist was met with laughter.

Even before the documentary was aired, whistle-blowers were on the receiving end of threatening letters from Britain’s most feared libel lawyers at Peter Carter-Ruck. Imagine if they employed some of the most expensive lawyers in Britain to tackle the people responsible for racism and not the people exposing it.

So what happens next?

Corbyn is so convinced of his virtue and impeccable anti-racist credentials that he really does believe he is the victim in all of this.

The truth is that Jeremy Corbyn and the hard left have taken over the Labour Party and want to turn it from a mainstream social democratic party into something very different. It is now a different party with a different leadership, different policies and different values, and the question for Labour MPs is how long will they put up with it?

Surely members of the shadow cabinet and all the MPs who claim in private to disagree with Corbyn must now show some leadership?

They are going to have to decide whether they can really appear on television or campaign in an election to tell people that Corbyn should be Prime Minister. That is what it will come down to. There will be no ducking this question when an election approaches.

It is no longer enough to issue a few angry tweets or to tell people like me privately that they understand why we left the Labour Party or that they disagree with Corbyn and the people around him.

And it is certainly not good enough to quietly assure representatives of the Jewish community that they are on their side, when they are serving as part of Corbyn’s front bench team – even in the shadow cabinet – actively helping him become Prime Minister.

We are long past that point: they know in their hearts that he has allowed the party to be poisoned by racism and extremism, that he has said and done things which are racist himself and that he is completely unfit to lead the Labour Party, let alone be our country’s Prime Minister.

It is time to show some leadership: Stand up, speak out and tell the truth.

Because if you are not in politics to do the right thing on an issue as fundamental as racism, what are you in it for?

Ian Austin has been MP for Dudley North since 2005. He resigned from the Labour party earlier this year.

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