Sir Wyn Williams, chair of the Post Office Horizon IT Inquiry, said he could not make a definitive finding that Horizon caused the deaths by suicide of all 13 people considered in the report. He did not rule out a causal connection as “a real possibility.” That is a serious qualification—not a finding that causation was proved.
What the inquiry chair said
In Volume 1 of the inquiry’s report, published in 2025, Williams wrote: “I should stress that whilst I cannot make a definitive finding that there is a causal connection between the deaths of all 13 persons and Horizon, I do not rule it out as a real possibility.”
The distinction matters: the chair left open the possibility that Horizon was connected to the deaths, but did not conclude that it caused all 13. The report’s subject is the human impact of the scandal and redress. The inquiry’s official reports and statements page lists Volume 1; the report is deposited on the UK Parliament website.
What the report recorded about suicide
- 13 deaths: The chair referred to 13 people who died by suicide. He could not make a definitive causal finding for all 13.
- At least 59 people: The inquiry received evidence from at least 59 people who said they had contemplated suicide and attributed this to their experiences with Horizon and/or the Post Office.
- 10 attempts: Ten of those people attempted to take their lives; some attempted more than once.
These are figures reported in the inquiry evidence, not estimates of the rate of suicidal thoughts or attempts among all affected postmasters or the public. The report does not say that all 59 attempted suicide.
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Why the chair did not make a definitive finding
Williams said he had not been provided with medical and other evidence that would allow him to reach conclusions about causation. The inquiry was also not permitted to determine civil liability. Its statement therefore recognizes a possible connection while making clear that the evidence and the inquiry’s remit did not support a definitive finding that Horizon caused each death.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Could the number of deaths be higher?
The chair said it was possible that more than 13 people had died by suicide and that some deaths had not been reported to the Post Office or the inquiry. He described this as a possibility, not a confirmed additional count. The figure established in the report’s passage remains 13 people.
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