Several former executives from the Post Office have testified in a public inquiry into the Horizon IT system scandal. David Miller, a former chief operating officer, expressed regret for not addressing known issues with the Horizon system after failing to read a critical report in 2004. He admitted that had he read the report by IT consultant Jason Coyne, which pointed out software discrepancies, he might have acted differently. The report was initially commissioned during a civil case involving sub-postmistress Julie Wolstenholme. Coyne was dismissed and his findings were discredited by the Post Office.

Additionally, David Mills, a former chief executive, testified that revisiting the Horizon system would have put the organization into “crisis mode.” Mills claimed he was unaware of the complaints about the software defects during his tenure, though he acknowledged that the prosecution of sub-postmasters should have been a focal point for the board of directors. He also admitted his lack of action after being aware of an expert report questioning Horizon’s reliability, stating he felt he was not “clever” enough to delve into the issues. The settlement with Wolstenholme was about £180,000, despite the Post Office risking a loss of £1 million in her lawsuit.

The inquiry has highlighted various issues regarding the management of the Horizon system and its impact, which led to over 700 wrongful prosecutions of sub-postmasters, reflecting broader concerns about corporate accountability and oversight within the Post Office. The investigation continues to unravel the complex dynamics and decisions surrounding the Horizon system’s implementation and the subsequent management failures.