The final closing statements are being made to the Post Office Horizon IT Inquiry and lawyers for key figures have submitted their last arguments.

Former Post Office boss Paula Vennells says, in her own written statement published online, she is “devastated” that information was “not shared with her” about the faulty Horizon IT system.

It is the first time the inquiry has heard from her since her appearance earlier this year.

Here are three summaries of some key submissions from Ms Vennells and other so-called core participants.

Paula Vennells

The former Post Office boss’s final legal submission states there was “nothing to show she acted in bad faith”.

As part of a bundle of closing statements Ms Vennells is described as someone who “wanted to do right by the sub-postmasters”.

She accepts that she “did not manage to uncover the truth about the matters” because “she herself was not told about issues which may have allowed her to do so.”

Her lawyers said she was “devastated” by the fact that information was “not shared” with her but that she “has no desire to point the finger at others”.

Her apology to the inquiry was also reiterated as part of her legal team’s 138-page written submission.

“Ms Vennells apologises unreservedly to all those who are affected by the matters which this inquiry is investigating,” it read.

While Ms Vennells admits she was the “holder of ultimate executive accountability”, her lawyers state that should “not be confused with an obligation to make every decision personally.”

She “relied” on briefings, reports and advice from “senior colleagues”, including IT specialists and lawyers, they wrote.

Her main argument is that the information passed on to her “was incomplete or wrong”, or that information “was not passed on” at all, adding therefore that “does not equate…to a failure on Ms Vennells part.”

Her closing submission also casts doubt, at times, on other witness testimony.

It states that contemporaneous documents rather than recollections, where disputed, should be relied upon.

Fujitsu

Fujitsu, which provided the faulty Horizon accounting system software, says it “fully acknowledges and accepts its share” of failings and “deeply regrets its role” in the suffering of Post Office victims.

Lawyers for the IT company state that the Horizon IT system, however, was “but one part” of the Post Office IT infrastructure.

It states that both Fujitsu and the Post Office “were aware from the outset” that bugs, errors and defects were present in the IT system.

The written statement admits that Fujitsu staff were able to access sub-postmasters’ branch accounts remotely.

It also describes IT training for Horizon users as “inadequate”, as well as Fujitsu and Post Office helpdesks.

Their lawyers point out that “miscarriages of justice” were not caused by “technological failures alone” but also ” the product of serious human and organisational failures in conduct, ethics, governance and culture”.

The IT company made a promise to “never again provide witness evidence of any kind in support of Post Office-led criminal investigations or prosecutions”.

Gareth Jenkins, former Fujitsu employee

Gareth Jenkins, a Fujitsu engineer, provided key evidence which helped in Post Office prosecutions of sub-postmasters.

Part of his defence is that he was “never formally instructed as an expert witness” and didn’t have “any formal qualifications” for providing that evidence in “a legal context”.

Mr Jenkins’s lawyers also blame the Post Office’s “systemic failings as an investigator and prosecutor”.

They describe “an agenda” that seeks “to make Mr Jenkins responsible for failures which were those of Post Office Limited alone… and which extended well beyond the relatively small number of cases that he was involved in”.

His legal team also describe an “astonishing” consequence of him not being “formally instructed” as an expert witness as this: “…not a single statement prepared by Mr Jenkins upon which POL [Post Office Limited] relied, in any of his prosecutions, constituted admissible expert evidence”.

He is accusing the Post Office of “actively misrepresenting” him to the role he was “required to discharge”.

Mr Jenkins denies he suppressed problems with Horizon, instead insisting that he volunteered information to the Post Office.

His lawyers describe failures by prosecutors as part of a “broader canvas of dysfunction”.