I had almost given up on finding a way to write about Official Secrets for the JC. I have been working on this thriller about Katharine Gun, the GCHQ whistleblower who leaked details of a US intelligence operation to fix the United Nations vote to go to war in Iraq, for the best part of a decade. But it didn’t seem to have a Jewish angle, no matter how hard I tried to find it. None of the main characters in the film are Jewish, nor any of the leading actors. The director is South African and the producer is a Brit of Irish extraction.

So much for the Jewish domination of Hollywood.

But then I realised the connection was staring me in the face: Official Secrets is the story of a brave whistleblower, a woman who was prepared to stand up and tell the truth as those around her kept their heads down. Those who have spoken up about antisemitism within the Labour Party will immediately identify with Katharine Gun.

As I write, I am preparing to present the film to an audience in Berlin, the capital of a country which understands the murderous cost of keeping quiet about institutional wrongdoing.

Here in Berlin another young woman decided to blow the whistle. In February 2019, a 27-year-old Labour Party employee, Louise Withers Green, came for a short break with a group of colleagues who had quit working for the party. She later told Jessica Elgot of the Guardian that the trip had a profound effect on her.

“We were really feeling the impact of what even just racist threats can become. Being faced with what that can lead to — it made it feel urgent that we did something.”

It is difficult not to be affected by Berlin. It gets under your skin because of the sheer weight of 20th century history: not just the Holocaust but the Cold War and its legacy of division that has fed the rise of right-wing populism in the east of the country. When she visited, Withers Green had been signed off sick from work, where her job involved preparing cases against members facing expulsion by Labour’s National Executive Committee. She had been obliged to sign a non-disclosure agreement but she returned from Berlin determined to speak out. As a result of her experience in Berlin, she decided to participate in John Ware’s BBC Panorama documentary, Is Labour Antisemitic?, which alleged senior Corbyn aides had interfered in the complaints process.

Louise Withers Green was not the only whistleblower to speak out. Another seven also came forward to give testimony to Panorama. But it is Withers Green who spoke so movingly of the visceral effects of that trip to Berlin and the power of the city’s history to persuade her of the need to act.

What links Gun and Withers Green is empathy. In Katharine’s case she felt she could not stand by as the US and its allies prepared for a war in which thousands of Iraqis would lose their lives. And Louise could not tolerate the rise of anti-Jewish hate in a party she had joined, in part, because of its record of fighting injustice and racism.

I have learnt a lot about whistleblowing during the making of Official Secrets and even more from the experts I have met during the many panel discussions I have taken part in across America, the UK and Europe. The Labour Party antisemitism crisis could be used as a case study in how not to deal with whistleblowers and cause maximum damage to an organisation as a result.

The latest management thinking suggests that badly-run organisations always treat whistleblowers as a virus that needs to be eradicated rather than “good bacteria” to be encouraged. It would appear the Labour Party didn’t get the memo. While paying lip-service to the idea the that it needed to address the problem, the organisation went on the attack against the whistleblowers. The statement released on the night the Panorama programme was aired is an exercise in personal vitriol suggesting the individuals involved were “disaffected former officials” including those driven by their opposition to Jeremy Corbyn’s leadership. “This throws into doubt their credibility as sources,” it continued.

A healthy organisation would have welcomed the exposure of race hate and put measures in place to allow its employees to better report it. Instead, Louise Withers Green and her colleagues felt the only place they could turn was the media.

Their fears that the Labour Party was not equipped to deal with their concerns was confirmed by the reaction. The Labour leadership chose to impugn the integrity of individuals who took considerable personal risk in bringing the poison in the party to the attention of the public rather than deal with the problem. The fact that Jeremy Corbyn himself condemned the programme suggested that the systemic organisational failure stemmed from the top.

As the election campaign gathers pace, the Labour leader must now feel he can’t move without tripping over an antisemite or someone trying to expose anti-Jewish racism within his party. Whistleblowers are everywhere: from high-profile celebrities such as Tracy-Ann Oberman and Rachel Riley to former MPs Dame Louise Ellman, Luciana Berger, John Woodcock and Ian Austin, who stood down from Labour in disgust.

The fears of those party employees who participated in the Panorama programme have been borne out by the number of prospective candidates discovered to have unfortunate “anti-Zionist” skeletons in their closet. The Equalities and Human Rights Commission investigation into institutional racism in the Labour Party continues and employees labelled disaffected by the leadership prepare libel actions. Meanwhile, Jeremy Corbyn is routinely labelled an antisemite and knows he can take no action against the most dishonourable of epithets.

Riley and Oberman have been the victims of appalling online abuse, while moderate Labour MPs have been driven out of the party they love. But this is not the worst of it.

All communities can and should be judged by how they treat their most vulnerable members and the same is true of a political party. Just this month Labour student activist Isobel Housecraft revealed that she had contemplated suicide after the backlash against her for speaking to Panorama. The 19-year-old Hull student had even been called a “dirty Jew” by a Labour colleague, despite not being Jewish. She was told there would be long-term consequences for her actions and that she had betrayed Corbyn. As a result she wrote a note to her family and friends apologising for failing them before she was persuaded against ending her life. Jeremy Corbyn should feel personal shame that a teenage Labour Party member considered suicide after revealing the truth about Labour antisemitism.

I have spent the past months travelling the world with Katharine Gun, one of the most courageous people I know. It has taken 16 years to get her story onto the big screen and win her vindication. People have sometimes asked why this story still matters but here in Germany they understand how important it is to establish the true historical record, however long it takes.

In time, Louise Withers Green will be vindicated. She has said that she hopes that in 30 years she will be proud of what she has done. It should not take so long.