After Alan Bates' moment it's the children of Subpostmasters who now need a voice: David Behrens

It perhaps helps to explain the culture of institutionalised lying that took root there: better to fib than risk your career by admitting your shortcomings – especially when you know you can get away with it.

Mr Bates, whose appearance before the Horizon IT inquiry on Tuesday was almost as dramatic as when Toby Jones portrayed him on ITV, timed his appearance to a tee. A few days earlier there had been the drip-feed release of covert recordings by Post Office investigators which proved the organisation knew years ago that its technology was as buggy as a guest house mattress.

In particular, the tapes revealed that the Reverend Paula Vennells, the spineless and sanctimonious chief executive at the height of the scandal, knew in 2013 of allegations that the accounts system could be accessed remotely – something she expressly denied to MPs.

Here at last was the smoking gun – and after all the other revelations it amounted to nothing short of a firing squad aimed squarely in her direction. It made her denials of culpability ring as hollow as a government levelling-up manifesto and she will have to explain herself to the inquiry next month.

But there remains one group of people in this sorry saga who have yet to be given a voice. They are the children – most of them grown-ups now – of more than 700 branch managers wrongly convicted by the Post Office because the Horizon software made it look as if money was missing from their shops.

Some of their stories are quite heartbreaking and Vennells, an ordained Anglican priest, would do well to reflect on them if she is to fully appreciate how grave a sin she committed in trashing the reputations of their families.

She might, for instance, consider the case of Adi Misra, whose pregnant mother’s wrongful imprisonment for nearly five months led him to contemplate suicide. It was his 10th birthday when she was sent down and the thought eating away at him was this: “What’s the point of living when my mum isn’t here?”

Doesn’t that just make you want to weep?

Then there’s Katie Downey, who was 11 when her father was falsely accused of stealing from his branch in the Lake District. It left him suicidal and the family had to flee to France, where Katie was bullied so badly that she temporarily lost the power of speech. For years she blamed her parents for the depression she suffered, not realising until much later that they were themselves victims of injustice.

Millie Castleton, whose father was portrayed in the ITV drama, was also bullied over the false claims made against her family. Her dad had to sell their home in Bridlington when the Post Office bankrupted him with debts of £321,000 despite having done nothing wrong and Millie, just eight at the time, grew up with an inherent distrust of people and an eating disorder.

Robbed of their childhoods, in some cases their education and even their sanity, these young people and others like them have formed a protest group called Last Chance for the Children of Subpostmasters. The challenge now facing ministers is to see that they are not left in the same limbo as their parents.

They can do this by requiring Fujitsu, the company that created the Horizon system and runs it to this day, to set up a trust fund with guaranteed payments to affected families as a condition of keeping the government contracts that have earned it £3.4bn since 2019.

They could also dock the wages of Post Office managers – who are after all their employees – and use the proceeds to compensate families who could really use the money.

Most fundamentally they can disenfranchise the Post Office by taking away its archaic power to prosecute people without recourse to the police. This above all is what fostered the belief among its bosses that they were above the law.

As for the Reverend Vennells, the question is whether she can reconcile her ordination – and what her bible says about the kingdom of heaven belonging to children – with the travesty she perpetrated as head of an organisation that delivered misery to so many young people.