As the BBC article which should have been linked quotes their attorney as saying, the post office is "an organisation that not only turned a blind eye to the failings in its hugely expensive IT system, but positively promoted a culture of cover-up and subterfuge in the pursuit of reputation and profit"
Whilst giving testimony in one case that there couldn't have been software errors, one of the Post Office executives was participating in internal communications regarding clear cut cases of software errors.
Yes, the software is bad, but these executives actively engaged in a cover up, in court. They should be prosecuted.
To play devil's advocate was there evidence of malfeasance besides the software?
If not, it is a bit disingenuous to say that the software did not send them to jail. If it was a witness who was mistaken and that was the only evidence, in standard english, we would say the witness sent them to jail.
https://www.bbc.com/news/business-56859357 https://www.bbc.com/news/uk-52905378
Also please don't post leading comments as being "devil's advocate". It's the laziest form of rhetoric, "just asking questions".