“The failure of the Labour Party to deal consistently and effectively with antisemitic incidents in recent years risks lending force to allegations that elements of the Labour movement are institutionally antisemitic.” That was one of the principal findings of the House of Commons Home Affairs Select Committee in the 2015-2017 parliament, of which I was a member. We made this finding in our report on antisemitism in the UK following a lengthy inquiry into the subject, which we published in October 2016.

It did not make for pleasant reading. Our report painted a picture of rising antisemitism in the UK over the last few years. There had been a 29 per cent increase in police-recorded antisemitic hate crime in England, Wales and Northern Ireland between 2010 and 2015, compared with a 9 per cent increase across all the hate crime categories.

Unfortunately, the picture has got worse, not better, since then, with figures from the Community Security Trust showing antisemitic incidents hitting a record high last year.

When talking about antisemitism, it is important to define the term. Broadly speaking, we adopted and endorsed the definition used by the International Holocaust Remembrance Alliance, though the committee proposed an additional clarification to ensure that freedom of speech is maintained in the context of discourse about Israel and Palestine, without allowing antisemitism to permeate any debate. What this definition makes clear is that antisemitism is a particular, distinct form of prejudice.

But it is also clearly a form of racism too. My father arrived in this country in 1964. In the general election that year, Britain saw the Conservative Party wage one of the most racist parliamentary elections ever seen in the West Midlands constituency of Smethwick, which included the use of a slogan I slightly adapt as I don’t want to repeat the full extent of its ghastliness here: “If you want a negro for a neighbour, vote Labour.”

One of the reasons my late father, a black man, always supported the Labour Party was because we historically have always been anti-hate and anti-racist, something which the Tories sought to use against us in Smethwick.

It was impossible for our select committee to do our inquiry in 2016 properly without looking at antisemitism in politics. Our report stated unequivocally that all of the main political parties have had various controversies and problems with antisemitism over the years. We questioned all the main parties in detail and took evidence – in public and private – as well. However, I am a Labour Party member. I joined the party, at least in part, because of its history of fighting racism and, while I don’t want to see any hatred or prejudice anywhere, I feel a particular responsibility to act where I see it in my own party.

So, when I questioned the witnesses we heard from in that inquiry – witnesses who included Jeremy Corbyn and the former Mayor of London Ken Livingstone – I was robust. I acted without fear or favour. I treated cross-examination with the seriousness and focus demanded by the issue, and would not let tribalism get in the way of doing so.

One member of Labour’s shadow cabinet at the time – he is still a member of it – told me he thought my questioning was inappropriate because, as a Labour MP, I should not publicly challenge the leader on anything. What he and many others fail to realise is that the issue of antisemitism and racism is not actually about Jeremy Corbyn (although his handling of it is obviously flawed). He is not the victim here – and the issue is far bigger than one party leader.

Our report found there is endemic antisemitism in parts of the Labour Party, and some of the evidence we heard was shocking. Despite that, some continue to deny that it was and remains a problem. One supporter of my party posted on my Facebook page commented saying our report was “utter rubbish” and said it was “a disgrace it was signed by a Red Tory and a Jew.” He was referring to me and David Winnick, the other Labour MP who was a co-author of the report and is Jewish.

Many who took exception to the report ended up proving their own antisemitism, somewhat ironically. A Labour Party supporter posted in response to my questioning of Ken Livingstone that “Chuka is well and truly in the pockets of ‘The Lobby’.” For the avoidance of doubt, he was not referring to the so-called lobby of Westminster journalists.

Another said on Twitter that we were “a bunch of embittered Zionists who are intent on smearing” Jeremy Corbyn. This accusation of smearing the leader has shamefully been parroted since by some members of the Parliamentary Labour Party.

Most disappointingly, in his response to the report, not only did our leader make basic factual inaccuracies about its contents but he seemed incapable of acknowledging the Labour movement has a particular problem with antisemitism. He even went so far as to insinuate that we were using the issue as a “weapon” (his words, not mine) for political purposes.

Coming from a family which has had direct experience of racism, I found this to be grossly insulting and offensive – I made my feelings clear about this at the meeting of the Parliamentary Labour Party which followed publication of the report.

It is therefore unsurprising that antisemitism has continued unabated in and around the Labour Party since 2016. Just this month, Peter Kirker – who is a member of the Campaign for Labour Party Democracy executive and has been a party officer in London and the Midlands – wrote in the Morning Star under the headline “Enough already with this Zionist frenzy”, in a piece which stated that “the noise around anti-Jewish racism has been engineered from within the murky right-wing world of British Zionism.”

The online abuse I quote above is, of course, nothing compared to the abuse meted out to Jewish Labour Members of Parliament and activists. My friends Luciana Berger, the MP for Liverpool Wavertree, and Ruth Smeeth, the MP for Stoke-on-Trent North, and others described in vivid detail the true awfulness of what they have been subject to last week. They have to live with this every day.

Sadly, even when there is an admission that antisemitism is a problem, too often it is followed by an avalanche of “whataboutery” by people in the party: But what about the Tories? But what about Gaza? But what about the bias of the mainstream media? Of course these are important issues. But the question on this issue is: if antisemitism exists in the Labour Party, which it clearly does, then what is the party going to do about it?

The constitution of the Labour Party says the Labour Party is a “democratic socialist party” and we seek to create, amongst other things, a community where “we live together, freely, in a spirit of solidarity, tolerance and respect”. It also says that we seek to create a society which “delivers people from the tyranny of prejudice”. As Martin Luther King said 50 years ago this month to America: “Be true to what you said on paper.” The Labour Party has lost its moral compass on the issue of antisemitism, and needs to reflect on the values it was founded upon.

It’s time to clear the large backlog of antisemitism cases in the party, rather than just sitting on them. It’s time to rebuild relations with the Jewish community, who understandably do not feel that Labour is a safe place for them. And it’s time to stop merging criticisms of the policies of Israel or capitalism with a commentary on Jewish people – something which happens time and time again in the party. How can we criticise the Conservative Party for running a racist, Islamophobic and prejudiced London Mayoral campaign in 2016, call them to book for delivering clearly racist leaflets last month in local elections Havering, or suggest racism lies behind the Tories’ mistreatment of the Windrush generation when we don’t get our own house in order?

Nothing currently illustrates just how broken British politics has become than the issue of antisemitism in Labour and the Tories’ appalling treatment of the Windrush generation – each of the main parties attacks the other on the issue, but both lack the credibility to do so in the eyes of many because of their party’s record on addressing prejudice within their own ranks.

A Jewish member of my constituency party – one of our most dedicated and active – emailed me a few weeks ago. She wrote: “What’s a dedicated Labour member such as myself supposed to do now? How many more incidents such as this should I take on the chin and stay in the party? How, when time and time again people I’ve supported and congratulated for winning elections turn out to hold antisemitic views, could I ever campaign and support anyone in the party, outside my immediate circle?

“Why should any Jewish person vote Labour?”

This is an instruction to act. We must do so.