Priller
Well-known member
I supposed the culpability of Fujitsu depends on whether or not the bugs were known to them, or ever reported by the Royal Post. From the sound of it RP just assumed that the software was right, despite the ridiculous volume of reports not really making sense, so likely never looked into possible software issues. Not to be an apologist or anything but not all corner cases are found in software testing and if they go unreported, there's little that a company can do.
Trying not to 'spoil' the series, but Fujitsu explicitly knew the software was deeply broken and had techs making changes directly to POS systems in the background to try and secretly fix the accounting discrepancies all while stating publically that absolutely nobody but the sub-postmasters would have access to that data and and remote changes were impossible. They absolutely knew the software was deeply broken but hid it and lied repeatedly. Their tech support script was explicit in stating to anyone who called their helpline that they were the only one with the problem, too, to discourage people speaking to one another. The Post Office was responsible for the choices to prosecute the employees instead of doing the right thing, but they did so partly to protect the reputation of the Horizon system for a multitude of awful reasons. Ultimately, the first point of contact from the users when they had issues was to the Fujitsu subsidiary rather than the Post Office themselves, so I'd argue that they knew much more profoundly that there were problems, and in fact we're active in obfuscating that information to the corporate Post Office at innumerable points.