The Post Office began rolling out the legacy Horizon IT system for accounting in 1999, which, along with its two subsequent upgrades, contributed to one of the worst miscarriages of justice in British history.

A timeline of what happened and the subsequent ramifications - The timeline of events involved in the Post Office Horizon scandal goes all the way back to 1999.

First part of the UK Horizon IT Inquiry Report points finger at Post Office and Fujitsu managers who “should have known that Legacy Horizon was capable of error.”

Post Office bosses should have known Horizon was faulty but “maintained the fiction that its data was always accurate” when prosecuting subpostmasters, the first tranche of a public inquiry’s final report has concluded.Chairman Sir Wyn Williams said “a number of senior” people at the organisation were aware the system, known as Legacy Horizon, was capable of error up until it was changed in 2010, with a number of employees also aware the updated system, Horizon Online, also had bugs and defects.A total of 59 victims of the Horizon scandal contemplated suicide with 10 attempting to take their own lives, Sir Wyn’s final report concluded.He said there was a “real possibility” 13 people took their own lives as a result of the suffering they endured during the scandal.Sir Wyn said around 10,000 people are eligible to submit compensation claims following what has been dubbed as the worst miscarriage of justice in British legal history.Lead campaigner and former subpostmistress Jo Hamilton said the report “shows the full scale of the horror that they unleashed on us”.The scandal was propelled into the spotlight in January last year following the airing of ITV’s drama Mr Bates Vs The Post Office, starring actor Toby Jones about Sir Alan Bates, former sub-postmaster and founder of the Justice for Subpostmasters Alliance.Ex-Post Office chief executive Paula Vennells is accused of overseeing a huge number of wrongful prosecutions and convictions, and was in post at the time Sir Wyn said bosses should have known Horizon was faulty.The chairman’s 162-page report criticised the “unnecessarily adversarial attitude” of the Post Office and its advisers towards making compensation offers to victims and that the organisation and the Government “simply failed to grasp how difficult it would be to provide appropriate financial redress.”Approximately 1,000 people were wrongly prosecuted and convicted throughout the UK between 1999 and 2015 as a result of faulty Fujitsu software, with a significant number contemplating self-harm, the report said.Sir Wyn also singled out the behaviour of Post Office investigators, saying subpostmasters “will have been in wholly unfamiliar territory and they will have found the experience to be troubling at best and harrowing at worst”.The publication of the first tranche of the report on Tuesday focused solely on the devastating impact of the scandal on victims and the compensation offered to subpostmasters, with a further report potentially attributing blame expected at a later date.Teasing his conclusions for the final overarching report, which is still likely to be some months away, Sir Wyn said: “Although many of the individuals who gave evidence before me were very reluctant to accept it, I am satisfied from the evidence that I have heard that a number of senior, and not-so-senior employees of the Post Office knew or, at the very least should have known, that Legacy Horizon was capable of error.“Yet for all practical purposes, throughout the lifetime of Legacy Horizon, the Post Office maintained the fiction that its data was always accurate.”Sir Wyn made a total of 19 recommendations as part of his report, including that the Government and the Post Office should make a public announcement about what they mean by “full and fair redress”.In a statement issued after the publication of the report, Sir Wyn said he is “critical” of the Post Office and the Government for the “development and evolution” of the compensation schemes.He also said the main scheme, the Horizon Shortfall Scheme (HSS), had been subjected to “egregious delays”.In his recommendations, Sir Wyn said claimants who apply for compensation as part of HSS, should be entitled to free legal advice.The chairman also addressed criticism of another scheme, the Horizon Convictions Redress Scheme, saying claimants should be entitled to the £600,000 fixed offer even if they submit their own detailed individual claim.Sir Wyn urged the Government to establish a public body to devise, administer and deliver compensation to those wronged by authorities.The report said the number of people eligible to submit compensation claims as part of the scandal is likely to rise “by at least hundreds, if not more, over the coming months”.In a statement, the Post Office said: “The inquiry has brought to life the devastating stories of those impacted by the Horizon Scandal.“Their experiences represent a shameful period in our history.“Today, we apologise unreservedly for the suffering which Post Office caused to postmasters and their loved ones.“We will carefully consider the report and its recommendations.”

Government bodies kept awarding Fujitsu with contracts to the tune of £500m even after the ITV drama Mr Bates vs The Post Office.

UK Post Office bosses should have known Horizon was faulty but "maintained the fiction that its data was always accurate" when prosecuting sub-postmasters, the first tranche of a public inquiry's final report has concluded.

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