Thursday 26 November 2015

Barrister criticises Post Office prosecution

Stephen Mason
Since 2011 I've been in contact with Stephen Mason, a barrister who is the author of a book on electronic evidence and the editor of a journal called the Digital Evidence and Electronic Signature Law Review.

Mr Mason has sought and received permission to publish the full transcript of Seema Misra's trial.

Seema Misra used to be a Subpostmaster at West Byfleet Post Office in Surrey. Despite being convicted of the theft of £75,000 from the Post Office by unanimous verdict at Guildford Crown Court in Nov 2010 (and subsequently sent to prison whilst pregnant), Seema has always protested her innocence. Her case is currently being considered by the Criminal Cases Review Commission.

Seema Misra
It was Seema's husband Davinder who made me aware of alleged problems with the Post Office Electronic Point of Sale and branch accounting system (Horizon) whilst Seema was still in prison. Seema was convicted on the strength of electronic evidence drawn from the Horizon system.

Since the BBC Inside Out South investigation in Feb 2011, alleged problems with the Horizon computer system and criticism over the way the Post Office suspended, sacked and prosecuted a number of its Subpostmasters has been the subject of a Select Committee Inquiry, two parliamentary debates (1 and 2), several more Inside Out investigations, two One Show pieces and a recent Panorama.

We know from the Panorama that the Post Office prosecuted one Subpostmaster for theft despite an internal investigator stating he could not find any evidence of theft. The Post Office says it cannot comment on individual cases due to confidentiality, but that a financial loss and false accounting together is often sufficient evidence for a theft charge. The Post Office maintains the Horizon system works fine and that it's never done anything wrong in any of the cases we've featured.

In his introduction to the Misra trial transcript, Mr Mason warns that the "the reader must take great care in reaching settled conclusions from the transcript of the trial, because the transcript is only one part of the entire record."

This does not stop Mr Mason from making considered, but repeated criticisms of the Post Office prosecution. Here he attacks a fundamental defence the Post Office have always made about the Horizon system - its "robust"-ness:

"To assert that a complex system, which the Horizon software appears to be, is ‘robust’, the prosecution ought to have produce [sic] evidence to establish what was meant by ‘robust’ and the truth of the claim. 
"No evidence was produced to demonstrate that the system was ‘robust’, nor to establish the ‘quality’ of the system – none of the test [sic] set out in chapter 4 of Electronic Evidence seem to have been considered. 
"The Post Office also failed to produce any evidence regarding the operation of the operating environment and the reconciliations, error rates, controls, and relevant internal audit processes used to ensure integrity, and to provide details of the various up- dates that fixed problems with the software."

He then goes on to address the issue of who actually controls the Horizon terminals in a Post Office:

"The comment that the defendant would have been aware of a defect in the software (excluding the specific defect discovered in a post office in Callendar Square in Falkirk) is manifestly incorrect.
"Neither observation was accurate, nor, it appears, sustained by any evidence produced at trial. Moreover, the observation (Day 1 Monday 11 October 2010, 23H – 24A) that Seema Misra was ‘the person responsible for the computer system at this office’ demonstrates the failure of the prosecutor to understand that end users of the Horizon system do not control the computer system: Fujitsu undertake this task."

Mr Mason then goes on to criticise the expert witness for the prosecution:

"Gareth Jenkins, the system architect for Fujitsu Services, was asked about the possibility that a problem that might arise between the systems [Horizon and Riposte], but he considered this was of no relevance, even though he did not know whether the problems encountered with the Riposte software might have affected the Horizon system (Day 4 Thursday 14 October 2010, 97 – 98).
"In effect, the prosecution did not present any witness for the defence to cross examine on this particular and important point, although it was admitted that the Escher software [Riposte] appeared to be the cause of the problem encountered at the post office in Callendar Square in Falkirk (examination in chief: Day 4, Thursday 14 October 2010, 46F – 50; cross examination: 88G – 111). 
"Mr Jenkins relied on a great deal of hearsay in giving his evidence, he rarely obtained and submitted original data, and on occasions spoke to other people in Fujitsu Services to ascertain answers to technical questions – yet none of the people he spoke to were called to give evidence."

The assertion that it was only Seema Misra who was having problems with Horizon appears to have been contradicted during the trial:

"The previous owner of the post office run by Seema Misra claimed that they did not have any problems. It later transpired that this was not correct (Day 5, Friday 15 October 2010, 2 – 9). 
"However, before the first owner of the post office made the additional admission, the prosecutor reached the false conclusion that because the first owner of the post office did not have any problems, it followed that there was no failure of the computer system at a later date (Day 1 Monday 11 October 2010, 50F)."

His conclusion:

"Arguably, the evidence of the software system was not sufficient for anybody to make a decision based on the evidence put forward in the trial [my italics], and it seems that all Professor McLachlan [expert witness for the defence] could do was highlight the fact that he had so little evidence to consider, that he was not able to offer any sensible or conclusive conclusions."

In summary, a barrister who specialises in the presentation of electronic evidence in court believes evidence presented by the Post Office during a criminal trial was "arguably" not sufficient for a jury  (or indeed "anybody") to reach an informed decision. In Seema's case the Post Office didn't offer any other evidence as to her guilt of theft, a point noted by the judge in his summing up to the jury.

A barrister's opinion is just that, a barrister's opinion. But the evidence required to convict someone of a criminal offence must be beyond reasonable doubt. Mr Mason believes the prosecution's evidence was arguably insufficient. The jury, without the benefit of Mr Mason's expertise, disagreed.

I've asked the Post Office to respond to Mr Mason's comments and will post up their reply if I get one.


Further reading:

Ongoing Computer Weekly investigation into Horizon and timeline
Post Office Horizon primer written by me in 2013


  1. Great piece Nick. The publication of this transcript is probably the final nail in the coffin for POL. It's taken me a while to read it and get to grips with what was said. But lets go back to Panorama and what POL came out with after that.

    They said "The Post Office wholly rejects extremely serious allegations repeated in BBC’s Panorama programme of 17 August 2015. The allegations are based on partial, selective and misleading information.

    The Post Office does not prosecute people for making innocent mistakes and never has
    There is no evidence that faults with the computer system caused money to go missing at these Post Office branches
    There is evidence that user actions, including dishonest conduct, were responsible for missing money"

    There is nothing partial and selective about the WHOLE transcript.

    POL prosecuted Ms Misra. They must have determined she was guilty of theft before they took that action. How did they come to that conclusion? There was no evidence produced in the trial to show that she deliberately took money and in fact the prosecution concurred there was no evidence to show that she had enjoyed any benefit from the missing amounts.

    Innocent mistakes happen all the time in PO Land. They must do otherwise how on earth do POL explain TWO MILLION POUNDS of losses in Crown Offices. So why did they decide Ms Misra wasn't making innocent mistakes. They relied totally on a CV to show she was intelligent enough to 'steal' the money. DOH! If she was that intelligent she wouldn't have. She not only knew she would be audited, she knew there was a shortage and she was trying to pay it back by borrowing from her Sister-in-Law.

    There is no evidence to show that the computer system caused these losses. There is no evidence to show that they didn't. This is where the judge and the law went sadly wrong. It is not for Ms Misra to prove that there was a computer fault, it is expressly for the prosecution to prove there wasn't - without reasonable doubt. That is something POL cannot and will never be able to do. All computer systems have faults and we now have the evidence to prove that not only do faults exist in the Horizon system that cause losses to subpostmasters, but POL are aware of these, do not inform the network that they exist and even worse wait 6 months before applying a software fix.

    The last sentence from POL is deplorable. It shows their incompetence, lack of understanding and low level of intelligence. Apart from the fact that no evidence of dishonest conduct with regard to how the losses occurred was offered by POL in the Misra case they have the temerity to continue to suggest there was. The main point though is 'Missing Money'.

    There probably was no "Money" involved here. Neither the defence or the prosecution pointed that out. Shame on them. Before you can steal something it does actually have to exist. In the latest example of a software fault in Horizon, the computer generated an additional three transaction of £8,000 each which resulted in the subpostmistress being liable to POL for that amount. The £24k NEVER existed. In the Misra case it seems that the onus to detect and report any computer error was placed on MS Misra. SOrry - but when she was interviewed did she pass an aptitude test in computer programming? More to the point was she made aware that POL knew of errors in Horizon but failed to inform her that when they found them they wouldn't tell her about them so she wouldn't know what to look for?

    The end is sight Nick. Hats off to you Alan, Stephen, Michael and others who have brought this to the attention of the press, the Government and now hopefully the Serious Fraud Office because at the end of the day I do believe criminal charges could and should be brought against POL management. Cheers, Tim

  2. you have kept the taxi waiting a long time Ms. Vennels !!