In depth: PO inquiry - Ex-Fujitsu engineer claims he was unaware of expert witness obligations

The name Gareth Jenkins has weighed heavily upon the public inquiry into the Post Office scandal. It was his testimony as an expert witness that secured the conviction of at least 15 sub-postmasters. In one case involving Seema Misra, who would be jailed while pregnant, Jenkins appeared in court to give evidence.

But Jenkins was not a Post Office employee. He worked for Fujitsu, the company that designed and operated the Horizon system which falsely calculated shortfalls in hundreds of Post Office branches.

His role as a witness came under scrutiny over four days of evidence at the inquiry this week (former Post Office chief executive Paula Vennells appeared for only three days). Key questions included: did Post Office lawyers make sure that Jenkins was cognisant of his duties as an expert witness – and did they cause him to alter his witness statements?

Jenkins maintained throughout his oral evidence that he had been ill-prepared, ill-advised and unaware of his obligations. He regarded himself as an expert on Horizon brought into legal proceedings to give background information, not an opinion.

He emerged as a key figure for the Post Office in 2006 when the organisation sued Bridlington sub-postmaster Lee Castleton over £27,000 apparently missing from the branch account.

Castleton’s defence lawyers (before he ran out of money to pay them) asked for disclosure of issues with Horizon. Very little was forthcoming, but Jenkins denied any wrongdoing. ‘I now know that I gave evidence without understanding that I might be subject to “expert duties” (depending upon the sort of evidence I was giving),’ he told the inquiry. ‘I also thought that I could trust the way in which POL lawyers conducted these cases and that, in turn, my approach was appropriate and correct.’

Jenkins told the inquiry he had not understood the difference between a civil and criminal court. He did not recall being told of his duties as an expert witness, and when he was told he would not be called for evidential reasons, he wrote: ‘I won’t try and understand what this means!’.

He also recalled that the handling of prosecutions was ‘fairly chaotic’ and that he had been bombarded with questions he had already answered.

'I now know that I gave evidence without understanding that I might be subject to ‘expert duties’ (depending upon the sort of evidence I was giving). I also thought that I could trust the way in which POL lawyers conducted these cases and that, in turn, my approach was appropriate and correct'

Gareth Jenkins

Inquiry counsel Jason Beer KC wanted to know if Jenkins ever felt pressure to stress the reliability of Horizon whenever defence lawyers raised doubts.

‘There were certainly cases where they were trying to put words in my mouth which I didn’t want to say… I just took it as being the way these things happened,’ Jenkins replied. The engineer would be approached directly by external lawyers asking for information on a case. One Fujitsu colleague said Jenkins was being ‘ambushed’ and Jenkins emailed a lawyer saying: ‘You should really be addressing such requests through Post Office Ltd rather than directly to myself.’

The inquiry saw evidence that, in one case leading to the jailing of a postmaster, Post Office investigator Graham Ward had wanted alterations to Jenkins’ statement. Jenkins had said in his draft that there had been a system failure and that these were ‘normal occurrences’. Ward wrote: ‘This is a really poor choice of words which seems to accept that failures in the system are normal and therefore may well support the postmaster’s claim that the system is to blame for the losses!!!’.

But there were times when Jenkins found it more difficult to argue he was a dispassionate expert who had not been properly briefed.

Internal emails showed that he referred to Misra as having ‘decided to jump on the bandwagon’ of blaming Horizon. When discussing another case on which he was asked for information, Jenkins wrote: ‘This is another example of postmasters trying to get away with “Horizon has taken my money”.’

Jenkins apologised for his choice of words but insisted he did not believe Horizon was at fault at the time.

Jenkins’ claim of ignorance of his expert witness duties was challenged on day two, when he conceded that he had seen a letter outlining what those duties were.

‘I had clearly not remembered about the fact I had seen this letter in 2006,’ he told the inquiry, but stressed that he still did not understand what was required of him.

Jenkins was also questioned about why he did not reveal details of Horizon bugs to Misra’s defence team. Were there concerns about the consequences?, Beer asked.

‘I can understand that now but I don’t think I was conscious of that sort of discussion,’ Jenkins replied.

The hearing continues.