Surviving the Post Office review – fresh details of the appalling scandal will make you even more angry

It is worth remembering that the ITV drama Mr Bates Vs the Post Office was only broadcast at the start of January this year, which seems remarkably recent given the extent of its impact. It dramatised the Post Office Horizon scandal , one of the biggest miscarriages of justice in living memory, and in doing so brought it to the very front of the conversation in public life. By painting the story in bold human colours, the programme showed the nation the fallout from the faulty Horizon IT system, owned by Fujitsu, which led to hundreds (at least) of Post Office workers being wrongly prosecuted for theft.

As Will Mellor discovers in the lean, powerful documentary Surviving the Post Office, the human cost has been appalling, and countless lives have been devastated. In many cases, the social consequences of these accusations were as horrifying as the legal ramifications. Those falsely accused of wrongdoing were ostracised, spat at and shouted at in the street. One woman recalls having a brick thrown through the window of her house. Mellor takes her to her old street after 16 years. She has not been able to face going back before now. What happens when she gets there is deeply affecting. Like her, many victims were forced to move. Their neighbours believed that they had stolen from pensioners and exploited their communities, when the employees were the ones being exploited.

The title has an ironic ring to it, as for the innocent workers it soon becomes clear that life after the Post Office has been transformed beyond all recognition. In the ITV drama, Mellor played Lee Castleton, who briefly ran a Post Office in Bridlington, which is why he is presenting here. Mellor knows, he explains, that “this role was more important than any other”, and it is hard to think of another series that has so successfully dragged injustice into the spotlight. He begins by meeting up with Castleton, which is a nice, slightly surreal jumping-off point. They have become friends, says Mellor, as Castleton talks about life since his brief time as a subpostmaster, in 2003 and 2004, when he was accused of stealing more than £20,000. As the drama showed, he was taken to court in 2007 and ordered to pay it back, in addition to the legal costs of the Post Office. He was forced to declare bankruptcy. Mellor asks him if he is angry. Not in the way that you might expect, he says, because he believes that his children deserve to have their father back “fully”.

To hear the stories afresh is newly infuriating and galvanising. The Post Office is still using the Horizon system

This initial chat over a cup of tea sets the tone for what follows, which is, perhaps, an even more clarifying account of the human consequences of the outrageous behaviour of the Post Office and of Fujitsu (both of whom offer their apologies, once again, in a caption at the end of the documentary). The families of those accused of stealing money feature strongly, and it is emphasised, over and over, that the people who went to court were far from the only ones affected. Katie and Thomas Watson were children when their mother, Fiona, was told that she could either accept guilt for the shortfall in her Post Office, repay the losses and return home to her family, or she could face full prosecution. She accepted responsibility for something she had not done. Their story is truly heartbreaking.

Tragically, they are not alone. The film-makers spoke to hundreds of people affected by the scandal. The scale of the trauma experienced by those who had done nothing wrong, and by the people around them, is miserable. But to hear their stories afresh is newly infuriating and newly galvanising. It reminds, or perhaps informs, viewers that the Post Office is still using the Horizon system. There is nothing to replace it. One remarkable woman, who has remained a post office operator even though she paid back money she never owed them, says that every week, every time she has to press that button, she feels sick.

In another caption, we see that the government has offered £103m to the Post Office to replace their IT system. You can only wonder why taxpayers are funding Fujitsu’s catastrophic mistakes. That’s Fujitsu, which has, since a court ruled in 2019 that its Horizon system was to blame for accounting errors in the Post Office, been awarded £1.4bn in government contracts .

The public inquiry into the Post Office scandal is ongoing, and is not due to conclude until next year. New information keeps emerging, keeps reiterating how truly awful and malicious it has been. Like Mr Bates Vs the Post Office, this small but mighty documentary brings it right back to the people who suffered, and are suffering, as a result.

• Surviving the Post Office aired on BBC One and is on iPlayer now.