Ex-judge Sir Anthony Hooper says the Post Office scandal is the "greatest scandal that I have ever seen in the criminal justice process"
He tells the Post Office inquiry "something went very, very wrong" and we need to "re-evaluate how we approach criminal cases of this kind"
Earlier, Lord Arbuthnot told the inquiry he was not happy with a "brush off" reply he had from a Post Office executive, after raising concerns about the system
Paula Vennells wrote to the former Arbuthnot - a leading supporter of wrongly convicted sub-postmasters - in 2012 to defend the Horizon system, describing it as "robust"
Arbuthnot also told the inquiry he was "frustrated" with successive governments' arm's-length approach to the Post Office when he raised potential issues
Between 1999 and 2015, more than 900 sub-postmasters were prosecuted due to the faulty Horizon system
Watch live coverage of the inquiry by clicking the play button at the top of the page
We're about to bring our live coverage of the Post Office inquiry to an end. You can read more about the key developments from today's hearing in this story.
And the background to the Horizon IT scandal is explained in this piece.
The page was written by Ali Abbas Ahmadi, Emily McGarvey, Sean Seddon and Alex Smith, and edited by Adam Durbin and Alex Kleiderman.
We've just finished hearing from Sir Anthony Hooper - chairman of the Post Office's mediation scheme - here's a quick roundup of what he said:
This morning it was the turn of Lord James Arbuthnot - you can see a summary of his evidence here.
Peter Ruddick
Business reporter
The success of the ITV drama 'Mr Bates vs The Post Office' means the key plot points of this scandal are now well known. But the thorough nature of an inquiry like this ensures it can still shock.
Take a four-minute exchange at just after 11 this morning. The campaigner Lord Arbuthnot recalled a meeting where he was, once again, told by the Post Office there were no issues with the Horizon IT system.
Jason Beer KC then listed various bugs and acquittals and cancelled investigations and asked if the former MP had been told about them at that meeting. Time after time the response came: "no".
Another word has been repeated a lot today: "Robust". It was the way Post Office officials described that bug-ridden system.
The man in charge of a short-lived mediation scheme - retired judge Sir Anthony Hooper - said that, looking back, there was never a chance of resolution so long as Post Office bosses 'robustly' maintained there was nothing wrong with Horizon.
Tomorrow, we start hearing from those former Post Office bosses. The stage has been set for the next act of this, still shocking, drama.
Azadeh Moshiri
Reporting from outside the inquiry
Speaking to David Enright, a lawyer for hundreds of sub-postmasters affected by the scandal, it’s clear he has nothing but admiration for the Tory peer, Lord James Arbuthnot, and his testimony today.
He says, “from myself and from the hundreds of people I represent I would say, bravo, my Lord”.
Enright believes the work that Lord Arbuthnot has done on behalf of victims is on par with Alan Bates’ own efforts.
He points out that Lord Arbuthnot not only campaigned on behalf of his own constituent Jo Hamilton, but also championed the cause of more than a hundred other constituents of other Members of Parliament.
As for his take on Sir Anthony Hooper’s testimony, he tells me it’s important given he was a Court of Appeals judge for two decades.
Enright was struck by Sir Anthony saying the case against the sub-postmasters "didn't make sense," and noted its “fundamental implausibility”.
He agrees, and adds, “it made no sense that the Post Office would accuse sub-postmasters when, just days after stealing thousands of pounds, they would have to immediately reconcile their accounts”.
Sean Seddon
Live reporter
Much of the evidence in the closing section of the hearing has been about the distinction between two criminal offences: theft and false accounting.
It's a technical legal matter but goes to the heart of whether the Post Office was abusing its powers to prosecute people.
The inquiry heard how the forensic accountants Second Sight brought in to investigate the Horizon system thought the Post Office was charging people with theft to pressure them into pleading guilty to false accounting.
Sir Anthony tells the inquiry he believes this view was correct. He says false accounting is generally treated as a lower offence in the courts and less likely to lead to a prison sentence, so sub-postmasters would be tempted to plead guilty to that in order to avoid a theft charge.
The inquiry chairman Sir Wynn Williams - who tends to keep rather quiet during these sessions - has just interjected to side with Sir Anthony’s interpretation.
An experienced judge himself, he says that in reality, false accounting and theft are treated differently by the courts.
Wrapping up his evidence to the hearing, Sir Anthony is asked if he has anything else to add.
"It's the greatest scandal that I have ever seen in the criminal justice process," he says of the the wrongly-convicted postmasters.
He appears to tear up as he says: "We've had many miscarriages of justice but nowhere as many as these.
"We need to re-evaluate how we approach criminal cases of this kind, and I don't envy the chairman's task in trying to find out how it all started - something went very, very wrong."
He adds he is "very worried" about the current approach to criminal justice trials and how they are prosecuted.
Sir Anthony is being asked about technical legal matters now - in particular, his internal arguments at the time that the Post Office should be disclosing more information to the courts.
He says: "I feared miscarriages of justice and I wanted everything to be done so people could have them quashed before they died."
Sir Anthony says he was in favour of disclosing as much material as possible in cases where people might have been wrongly convicted.
He denies his approach was “throwing open the warehouse door” and describes the Post Office as making excuses to avoid disclosure.
The inquiry's counsel moves on to differences in opinion between Sir Anthony Hooper and the Post Office and their legal advisers.
The notes of a meeting between Sir Anthony and Paula Vennells about the possible outcomes from the mediation process, show the former scheme chairman had suggested apologising to sub-postmasters where appropriate.
Sir Anthony says he continues to hold that view and has "always held that view".
He criticises governments and institutions for withholding an apology, saying: "Instead of saying 'I'm sorry something went wrong', they continue to fight it out, often at huge cost to everybody."
When questioned about a Post Office lawyer's concern that apologising may increase the likelihood of an appeal, Sir Anthonywas that "by at least the middle of 2014, was there were likely to have been serious miscarriages of justice."
Quote MessageMy initial view that it was very unlikely that these people had stolen money remained. I wanted people who had suffered so badly, [...] I wanted people to get on, identify their miscarriages of justices by one route or another, and get their convictions quashed. That's what I wanted.
Sir Anthony Hooper
Sir Anthony continues to take issue with the Post Office's account from that time, which still held there was no evidence of systemic flaws in Horizon.
He says we now know the Post Office's version of events "to be complete rubbish", but that the mediation process did not find "smoking gun" evidence showing fundamental flaws in the system.
Sir Anthony says the mediation process was never going to reveal that crucial evidence because of the way it was set up, and it was only possible later when historic data was analysed in depth.
The inquiry moves forward to March 2015 and the end of the mediation scheme's working group.
The Post Office sent an email to Jo Swinson, who was postal affairs secretary, saying it has become "increasingly apparent" the scheme isn't working and "taking too long".
It also claimed that the Justice for Subpostmasters Alliance are "refusing to engage", while some "MPs have publicly withdrawn their support", and says delays were due to others within the working group calling for a wider scope of investigation.
Sir Anthony interjects making it clear he doesn't agree with this statement.
He says that "the scheme was working as it was intended", and they "were dealing with the problem" of investigations taking too long.
He adds that it is "not true" that JFSA were refusing to participate, and they had only refused to take part in a "pretty minor matter" over mediation.
Sir Anthony Hooper is asked about a thematic report produced by Second Sight, and his decision to send it to those mediation scheme applicants referenced in it - despite the Post Office's attempts to delay.
He tells the inquiry he is struggling to recall the details of whether there was a vote on it during a meeting, but says he remembers that it was a "hot topic".
He acknowledges that it was his decision to release the report despite the Post Office's objections, and emphasises that he "wasn't to do with the merits, I was concerned with procedure".
"I was concerned that Second Sight produced their report, and that that report goes out."
After a short break, the inquiry is shown internal notes which reveal by June 2014, high-level discussions were taking place about removing Second Sight from the mediation process - even when progress had begun to be made on advancing some of the cases.
It shows there was concern about a consensus forming that the process should be kept the same for another 18 months.
The Post Office was aware that would take it past the 2015 election, which would be “enticing to ministers - who can point to an established process between now and the election”.
Sir Anthony Hooper says he had no awareness of these discussions taking place at that time.
Sir Anthony says the structure of the mediation process meant the "smoking gun" evidence about systemic problems with Horizon was never going to emerge via its work.
He says he was drafted in to look at individual cases, which were often years old and very complex.
Sir Anthony says the wider problem is that there was "never an in-depth investigation" into Horizon as a whole.
And asked about what the barrier was to resolving issues in the mediation process, Hooper says it was that the "Post Office would not accept any problems with Horizon".
"Therefore nothing could really happen," he says.
The inquiry is shown a report tabled by Second Sight, which Sir Anthony Hooper says the Post Office was "unhappy with".
Asked what his view was, Hooper says he was an independent chairman, and "was not in a position to make an assessment - I was trying to be independent".
He says the meetings themselves were civilised and there was "no shouting or arguing".
However, he adds: "The Post Office would not budge from position that the Horizon was robust. If that's your starting point then anything that criticises how the Post Office handled a case, it's going to be criticised".
"In the view of the Post Office there was nothing wrong. We now know it wasn't robust".
Sir Anthony says he does not feel that the Post Office were "dragging their feet" in preparing the reports on the cases for the mediation scheme, stating they were very difficult to prepare.
He says he disagrees with Alan Bates's conclusion that they were moving too slowly. "There was too much work," he says.
Sir Anthony adds that he spoke often to executive Angela van den Bogerd about the process and how he could help and whether they could speed it up.
Image source, Post Office InquiryLater, Sir Anthony is asked about his criticism of Alan Bates's comments that the Post Office were delaying their investigation.
"I felt the Post Office were seeking to deal with it in the time that they needed, says Hooper, and I said that."
He again makes the point that his criticism had nothing to do with the merits of Bates's case, it was all to do with procedure.
The inquiry is shown an account of a meeting involving Paula Vennells from March 2014 which gives an insight into some of the discussion taken place behind closed doors at the time.
It shows the then Post Office boss discussed "capitalising" on what they thought might be souring relations between Sir Anthony and Second Sight.
As detailed in the preceding post, Sir Anthony has clarified he had faith in Second Sight but had asked for reports to be structured more clearly.
However, sensing a breakdown between the two key parties in the mediation process, senior Post Office staff discussed whether they could gain from the situation.
It reveals Vennells was concerned about "forcing the point too much", and was worried Sir Anthony "might start to rebel if he feels he is being pushed in that direction".
The inquiry is shown a readout of meeting between ex-Post Office CEO Paula Vennells and Richard Callard, a senior civil servant at UK Government Investments, then a division of the Department for Business, Energy and Industrial Strategy.
Callard said at the time that Sir Anthony Hooper sent Second Sight reports back to them because he considered them to be "substandard and unsubstantiated".
He added that Sir Anthony "gave his idea" of what the general framework should cover and said this meant "his faith in Second Sight is waning".
Hooper rejects this as fair or accurate. "Not at all, I did not think they were substandard or unsubstantiated, my faith was not waning, I just thought the reports could be written more clearly".
Hooper has been going over the complexity of the mediation process in detail, using meeting notes and other documents sent between the Post Office and Second Sight that Inquiry counsel Julian Blake is pulling up on screen.
Hooper's frustration at the process is clear through the manner in which he is speaking.
He says the Post Office reports - produced as part of this mediation process - repeatedly said that there was nothing wrong with the Horizon system and the sub-postmasters were involved in "either theft of some form of carelessness."
Sir Anthony becomes very animated when asked about the Post Office's decision to sack Second Sight - the independent firm it had brought in to investigate claims - describing it as "ridiculous".
The inquiry's lawyer points out the minutes of Sir Anthony's remarks at the meeting where that decision was announced paint his response as fairly calm.
Does he think they were toned down somewhat, he's asked. Sir Anthony laughs and admits "I'm not very measured" at times.
He says he believes Post Office chief Paula Vennells was under pressure from the board to dismiss Second Sight because of cost and the potential fallout.
"I would have liked to get over to the board the fundamental implausibility of the Post Office's case" that thousands of branch managers were stealing, he adds.
As a reminder, Sir Anthony Hooper, a former Court of Appeal judge, was the independent chair of the mediation group that had been set up between the Justice for Subpostmasters Alliance (JFSA) and the Post Office.
The inquiry's barrister puts it to Hooper that concerns were expressed by Post Officials that the forensic accountants, Second Sight, who were appointed to look into the Post Office's IT system, had not come across as independent and was "unduly influenced by a need to satisfy certain MPs".
"Was that communicated to you?" Julian Blake asks.
Hooper says he would have "refuted it completely; they were being very independent".
"They were coming to conclusions that the Post Office didn't like."