For those trying to understand the English postmasters miscarriage of justice, this (from before the latest ruling) is the best, most readable read I've seen so far: https://www.private-eye.co.uk/pictures/special_reports/justice-lost-in-the-post.pdf.

(Likely a bit biased of course as Private Eye is involved in some respects, but still.)

"At a time of huge stress, the sub-postmasters’ legitimate options were either to accept the shortfall, making it their personal liability, or to refuse to sign off the accounts as correct... For many, either choice spelt ruin."

"The other possibility was to sign off the books by saying, incorrectly, that the funds did match the Horizon number and hope that what they felt sure was a computer glitch would correct itself. For people desperately worried over the loss of their livelihoods...

... who knew they’d done nothing wrong, this didn’t seem like an inherently dishonest move. But it played into the hands of a calculating and draconian Post Office prosecution service."

"When she called the Post Office auditors in the hope of resolving her problems, she received no sympathy. Instead, she was charged with false accounting and theft – despite Post Office investigation documents which later came to light stating: “There is no evidence of theft.”"

"The theft charge was in reality a tool to leverage a conviction for false accounting, triggering recovery powers under proceeds of crime laws. "My lawyers had struggled to get any disclosure from them so I was advised to accept the plea bargain – because they could not prove...

... I hadn’t taken the money even though the Post Office couldn’t prove that I had. I was told I would be less likely to go to prison for false accounting and felt I had no choice at all. I was terrified of going to prison.”

As others have noted, there are similarities to robodebt, albeit smaller in scale. But this scandal is significantly worse in several respects: the debts were not just not proven, but created by the PO; and dozens were wrongly prosecuted, with many imprisoned.