Paula Vennells

Ms Vennells was in senior roles at the Post Office when it prosecuted hundreds of sub-postmasters for theft and false accounting - despite many raising concerns about the IT system.

Some were left bankrupt or imprisoned and many were shunned by their communities, but the charges were false.

More than a million people signed a petition calling for Ms Vennells's CBE - awarded for services to the Post Office and to charity - to be revoked.

After days of pressure, she agreed to hand back the honour.

Ms Vennells first joined the Post Office as group network director in 2007 and was promoted to chief executive in 2012.

Alongside her career, she was ordained as a priest and served at three churches in Bedfordshire.

The year Ms Vennells took charge, the Post Office bowed to pressure to investigate after several sub-postmasters raised concerns about the Horizon system.

It commissioned a report by investigation firm Second Sight, which ultimately concluded there were no widespread accounting or IT issues.

Ms Vennells told a parliamentary committee in 2015 there had been no evidence of any miscarriage of justice.

But in 2017 a group of staff managed to bring its case to the High Court.

As it progressed, Ms Vennells faced increasing criticism and eventually stepped down in 2019, having been paid £4.5m during her time as boss.

The judge said the sub-postmasters should have their convictions quashed and described the Post Office's evidence as "institutional obstinacy".

After announcing she was returning her CBE, Ms Vennells said she was "truly sorry for the devastation caused to the sub-postmasters and their families, whose lives were torn apart by being wrongly accused and wrongly prosecuted".

She left the Post Office in 2019 and became chair of Imperial College Healthcare NHS Trust.

However, as the scandal grew, she quit in December 2020 for "personal reasons".

Angela van den Bogerd

The Post Office executive worked there for decades, holding roles including head of partnerships - and despite the growing scandal was made business improvement director in 2018.

She's understood to have handled complaints about the system and sat on a working group to deal with the fallout from it all.

Portrayed in the series by former Coronation Street actress Katherine Kelly, her evidence was fiercely criticised by a judge when hundreds of sub-postmasters won their case in March 2019.

Mr Justice Fraser said "she did not give me frank evidence and sought to obfuscate matters, and mislead me".

Ms van den Bogerd left the Post Office in 2020 for a job as head of people at the Football Association of Wales.

However, just a year later, she left after the departure of its chief executive following a no confidence vote.

At the time, sources at the Welsh FA told the BBC its ruling council had voted to get rid of her due to unease over her role at the Post Office.

It's unclear if Ms van den Bogerd is working again. She reportedly had a LinkedIn profile until recently, but it now doesn't appear in search.

Read more:
What is the Post Office scandal and why has it taken so long?
The devastating effect on the victims wrongly accused

Gareth Jenkins

The former chief IT architect for Fujitsu, the company that designed Horizon, provided evidence and reports backing up the reliability of the system in a number of Post Office prosecutions.

He's been investigated by police amid concerns his court evidence wasn't consistent with information he may have had about problems with the system.

Mr Jenkins has asked the public inquiry for immunity against incriminating himself, but it's refused to pass on his request to the attorney general.

He was due to appear twice in 2023, but on each occasion, it was postponed due to disclosure failings by the Post Office.

In the last instance, in November, it had to be postponed again after a last-minute dump of 3,045 new documents.

The inquiry chairman said it was a "source of frustration" but the documents needed to be processed and disclosed to Mr Jenkins before he gave evidence.

A rescheduled date for his evidence is still to be set.

Some MPs have called for Fujitsu to help pay for compensating Post Office staff.

Work and Pensions Secretary Mel Stride suggested it might have to contribute if the inquiry concludes it made mistakes, saying it "won't necessarily just be the taxpayer" who is "on the hook for this money".

Fujitsu said it's "fully committed to supporting the inquiry in order to understand what happened and to learn from it" and that it previously apologised "for its role in their [sub-postmasters'] suffering".

Alan Bates

Mr Bates gave his name to the ITV drama Mr Bates Vs The Post Office, which brought the case to a wider audience and sparked outrage over the injustice.

Part of the Justice For Subpostmasters Alliance, he was one of six lead claimants in the original court battle and led the campaign to expose the scandal.

Played by actor Toby Jones in the series, he moved from Yorkshire to run a post office in the seaside resort of Llandudno in North Wales for five years.

Mr Bates believes he was dismissed because he flagged up problems with the Horizon system.

He's now pushing for swift compensation for victims - many of whom are still waiting for payouts.

Mr Bates said dozens of people have died over the years without compensation or seeing their name cleared.

Prime Minister Rishi Sunak has backed calls for the former sub-postmaster to be knighted for his work spearheading the fight for justice.

Mr Bates has welcomed the ITV show but said it "couldn't cover all of the human loss and suffering" as it's "an enormously complex and vastly diverse story".

"There are hundreds and hundreds of people and families who have been affected," he said.

"What I hope people will realise is that in many cases, even now, the real story is not finished."

Tim Parker

A former Post Office chairman, the multi-millionaire joined in 2015 and held a vital position as sub-postmasters fought for the truth.

Much of his tenure was shrouded in controversy and he made a timely exit in 2022, a week before the independent public inquiry into the botched IT system began.

One ex-postmaster, Damian Owen, told the inquiry a letter he received from Mr Parker was "the most feeble apology I have ever received from anyone in my life" - inviting him to get in touch but providing no contact details.

Mr Parker earned the nickname 'the prince of darkness' for his tough cost-cutting approach in previous roles with firms such as the AA and Clarks shoes.

He stood down as chairman of the National Trust in 2021 amid a political controversy and was previously chairman of luggage maker Samsonite.

His wealth was estimated at £247m by the Times Rich List in 2018.

In 2020, Mr Parker said he was "sincerely sorry on behalf of the Post Office for historical failings which seriously affected some postmasters".

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He said the firm was "resetting its relationship with postmasters with reforms that prevent such past events ever happening again".

"All postmasters entitled to claim civil compensation because of their convictions being overturned [should be] recompensed as quickly as possible," he added.

Sir Ed Davey

The now leader of the Liberal Democrats was postal affairs minister between 2010 and 2012 when prosecutions were ongoing.

He refused Mr Bates's request to meet him in 2010, saying in a short three-paragraph letter "it wouldn't serve any purpose".

Sir Ed said the Horizon IT system was "an operational and contractual matter for POL [the Post Office] and not the government".

He did later meet Mr Bates and said he passed on concerns to management - but didn't intervene in any cases.

The Lib Dem boss has now said he was "clearly misled" by executives.

"I wish I had known then what we all know now, the Post Office was lying on an industrial scale to me and other ministers," said Sir Ed.

He added: "My heart goes out to all those people, we need to make sure their convictions are overturned and we need to make sure they are fairly compensated, and quickly."

Political rivals have accused him of taking "the side of the employers over the workers".

Tory deputy chairman Lee Anderson urged him to make a public apology and said he'd taken the "side of the Post Office employers and sadly many went to prison due to him not listening".

Nick Read

Nick Read has been chief executive of the Post Office since September 2019.

Before joining he was group chief executive at Extra Energy and prior to that chief executive at Nisa Retail Limited.

Speaking to MPs on the business committee on 16 January, he said the company has still "not got to the bottom of" what happened to the cash paid by sub-postmasters and mistresses in a bid to cover the false financial black holes created by the Horizon software.

He said it has been investigated two or three times by external auditors, but it is something "we have struggled to uncover" due to various issues, including a low quality of data.

However, he admitted it is a possibility the money taken from branch managers could have been part of "hefty numeration packages for executives".

"It's possible, absolutely it's possible," he said.

Mr Read said the information has been provided to the statutory inquiry into the Horizon scandal, which will look into the question of where the money went.

Paul Patterson

The director of Europe's Fujitsu Services Limited appeared alongside Mr Read during questioning by MPs on the business committee.

Mr Patterson told MPs he was sorry on behalf of his company - as he accepted it would have to pay into the redress scheme.

"Fujitsu would like to apologise for our part in this appalling miscarriage of justice," Mr Patterson said.

"We were involved from the very start.

"We did have bugs and errors in the system and we did help the Post Office in their prosecutions of the sub-postmasters and for that we are truly sorry."

He said the company gave evidence that was used to send innocent people to prison, and while he did not know exactly when bosses first knew of issues related to Horizon, it had bugs at a "very early stage".

Mr Patterson, who has been in his current role since 2019, said he did not know why the tech firm did not act when it knew there were glitches in the system.

"On a personal level I wish I did and following my employment in 2019, I've looked back on those situations for the company and from the evidence I've seen, I just don't know."