♪ ♪ We'd all had our lives completely tipped upside down.

NARRATOR: This is the story of one of the widest miscarriages of justice in British legal history.

♪ ♪ I went through hell.

ALAN BATES: It was diabolical.

Something had to be done about it.

♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ ♪ JO HAMILTON: The village shop and post office had come up for sale.

Someone suggested that I would be the perfect person to take it over.

NOEL THOMAS: I started my first job as a postman back in 1965.

And in 1994, I took over the post office.

♪ ♪ JESS UPPAL: I passed my interview, so, yeah, I was given the position, and everything was perfect.

HAMILTON: We had a group of pensioners who would come in to get their pension every week.

(sheep bleating) Very much part of a community.

28p, please, love.

How much?

BATES: You do get to know your locals.

(dog barking in background) We'd have a good banter, a good laugh with every... all the customers-- it was really good.

You're not only their postmaster, you were also an adviser to people.

Jo?

It was lovely.

You felt like you were actually the heart of the village.

ISSY: Morning!

With you in a minute!

No rush.

HAMILTON: It was idyllic.

I felt that I've managed to get myself a good position as a postmistress-- it's not easy.

HAMILTON: The idea was that it would be my retirement business.

UPPAL: I thought I was gonna spend the rest of my life there.

But I didn't know what was ahead of me.

I went through hell.

♪ ♪ BATES: It was diabolical.

Something had to be done about it.

♪ ♪ Look, Alan!

Look what we did!

Look what you did!

REPORTER (on TV): Should the Post Office bosses go to prison, too?

LEE: All right, enough, come on, Noel.

No, no, no.

Hit them in their pockets.

Hit them in their pockets.

That's what you want to do.

That's, that's what's gonna hurt them.

NARRATOR: This is the story of a saga that began nearly 25 years ago.

We were not mad, were we?

(laughs) RON WARMINGTON: Dealing with Post Office has been more difficult than dealing with the mafia.

It's like fighting a steam roller.

NARRATOR: A group of subpostmasters from all over the U.K. fought to expose one of the widest miscarriages of justice in British legal history.

WOMAN: We want answers now, to know who's actually done this to so many people and why.

♪ ♪ FILM NARRATOR: There begins the long chain of accounting, and every ha'penny of every transaction accounted for.

NARRATOR: The Post Office was established in 1660, and had always used paper and pen to balance the books.

But in 1999, management introduced something completely new.

♪ ♪ A computer system called Horizon.

It was the biggest I.T.

rollout in Europe.

The Post Office connected 40,000 terminals across the country to one central hub.

HAMILTON: An engineer arrived.

He screwed it on the desk, and I asked him what it was, and he goes, "That's Horizon.

It's going live shortly-- you'll hear all about it."

It was great-- I was really enthusiastic.

I'd been involved with developing, um, bespoke software packages where I'd worked before, and I was all for it.

Basically, I never had a problem balancing until that was installed, and then, a couple of months after that, I had a very big shortfall at the end of the week.

It said I was minus £2,000.

Just overnight, £11,000 of stamps had gone missing.

BATES: I suddenly found I had £6,000 shortfall.

And I couldn't understand where that had gone.

That was a ridiculous amount.

NOEL THOMAS: There was no way of going back and checking stuff, like you did with the paper, 'cause once you pressed that button, it had gone.

♪ ♪ (phone ringing) HAMILTON: I rang the help desk, and they told me to do various things, which doubled the shortfall to minus £4,000.

When I rang the helpline, I was told that there was nobody else having these problems.

Oh, yes, the helpline was telling you, "Nobody else has got a problem.

You're the only one."

"You're the only one this is happening to."

"You're the only one."

That's what they kept saying.

Then I started feeling like I was going mad.

I knew I wasn't computer-literate, but I wasn't stupid, either.

In the end, you were totally confused, and nothing was done.

♪ ♪ NARRATOR: Under the terms of their contracts, the 20,000 subpostmasters were liable for any shortfall, whatever the cause.

When it got to about £9,000 short, I told my parents and I, and my husband, and I said, "Can we re-mortgage and put the money in?

"'Cause I've got no idea what's happening, but I've got to make it good."

And my mum went down to the building society and drew it out, and we put it into, the money into the safe.

Every week, I was putting money in myself.

So we basically went through the cash until it all ran out, and, to try and make up the balance every day.

It was just up and down, up and down.

It was never, ever right.

And on the end of the month, when we had to do the main balance, that's when it all used to come out, like... "Where, where's this money gone?"

And the amount kept growing, so I then didn't say anything.

I kept quiet, and let it grow to £36,000, terrified of what was gonna happen.

♪ ♪ NARRATOR: In North Wales, one subpostmaster took a different approach.

♪ ♪ BATES: I had £1,000 of shortfall, and I've never been accepting the figure that Horizon had thrown up each week, because I always felt that if I cleared it, I was accepting the Horizon system's figures.

And I wasn't prepared to do that.

Eventually, they got round to telling me I had to do it, or else.

And I said, "I won't do it, not until I have access to the system."

And eventually, they decided just to terminate my contract without giving me any reason, and that was it.

So they walked off with my life savings, and they decided to give my Post Office to somebody else.

Horizon's just created a whole batch of worry, not just for me, but for subpostmasters all over the country.

♪ ♪ HAMILTON: I shall probably clean at least till I'm 70-ish.

I'm resigned to the fact that I, I only have the state pension, and unless I sell my house, I need to keep working.

♪ ♪ NARRATOR: The Post Office used their sweeping powers to bring private prosecutions against their own employees.

In 2003, they went after Jo for the money they said she'd stolen.

I was originally charged with theft, and I pleaded not guilty, and we almost got to trial, and they offered up a plea bargain at the 11th hour.

And said, "Well, if you plead guilty to false accounting, we'll drop the theft charge, provided you repay the money."

NARRATOR: That meant Jo was forced to borrow in order to pay back the £36,000 the computer said was missing.

I could only raise £30,000 on the house, so we had a village meeting.

And I had to explain to everybody that I was in trouble in the Post Office, and someone put up their hand and they said-- 'cause it was November-- they, they said, "Well, couldn't Jo have an early Christmas present?"

And... From the moment I told them, I thought they were all gonna think I'd stolen money, and they didn't.

It was quite the opposite, and, um, yeah.

It was very humbling.

Literally, thousands of pounds went through the, the letterbox.

I think we'd reached it in about two weeks, and, yeah.

INTERVIEWER: Wow.

My village.

(laughing) (shop bell ringing) ♪ ♪ NARRATOR: When she went to court, the village showed up again.

HAMILTON: I just looked at the judge, and he goes, "Well, I'm not considering a custodial sentence."

Well, I was literally...

The, just, the tears were streaming down my face.

NARRATOR: Jo was sentenced to a 12-month supervision order.

But there were other people whose ordeals left an even greater mark.

UPPAL: We had a lot of happy memories here.

Especially when the children used to come off the bus, we used to look forward to seeing them after school.

They used to come running, running across this road, yeah.

And I enjoyed being here, as well.

Would've handed it over to them.

A lot of happy memories.

But they all got broken.

NARRATOR: In 2009, the Post Office charged Jess with the theft of £5,000, and her face was splashed across the local papers.

Family members actually went round to the shops, local shops, and gathered as many papers as they could.

It was also in one of the Punjabi papers, as well.

So basically, everybody read that story and pointed fingers.

We had somebody come in and spit on the floor, as well.

(glass shattering, alarm blaring) We had car windows broken.

You know, they did try and, you know, traumatize us, really.

And I would get this feeling that everybody else is thinking that "she's a thief."

And thinking about it day and night, day and night, I just wanted to end my life.

♪ ♪ I'm showing you the box.

(dog barking in distance) We can cross quickly.

And this is where the Post Office was.

NARRATOR: Noel Thomas became a postman at the age of 17.

In 2005, when his nightmare began, he'd only ever worked for the Post Office.

There we are.

We're by the box, which was the post office that my wife and I ran for, um, 36 years.

You know, it was a betrayal, wasn't it, when we lost this.

At half past seven, there was a knock on the door, and, uh, there was a lady and a gentleman in the door, and said they were Post Office auditors, and so I let them in, made them a cup of tea, and I told them straightaway that I was, um, about £52,000 down, so all hell let loose, innit?

♪ ♪ NARRATOR: Noel was arrested and questioned at a police station.

NOEL THOMAS: She was just, "Where was the money?

", and, "Where was the money?

", and, "What did you do with it?"

You know, and it was, it was really aggressive.

NARRATOR: Then the Post Office did to Noel what they did to many other subpostmasters: they offered to drop the theft charge if he agreed to plead guilty to false accounting.

♪ ♪ I remember me telling him, "Will it keep me out of jail?"

And he said, "Yes."

♪ ♪ But unfortunately, when I went into court, the judge came to his sentencing words, and he said, um, "Nine months."

And he sort of paused.

And I waited for a suspended sentence.

But he said, "Take him down."

I'd been a councilor, I'd been a postmaster, I'd been a postman, and highly thought of.

All of a sudden, it was all taken away from me, like taking a mat from under your feet, if you like.

It was bloody horrible.

♪ ♪ ♪ ♪ KARL FLINDERS: My journalistic life has been dominated by this.

I mean, it's the biggest story I've worked on.

It's probably the biggest story I'll ever work on.

♪ ♪ NARRATOR: In 2009, the story hadn't hit the press yet.

Social media was in its infancy.

Even though many subpostmasters were being prosecuted, each one of them thought they were the only one.

But that was about to change.

This particular article began because we were contacted by a subpostmaster about his problems.

Often, when you get contacted by a single person, it's very hard to stand up a story.

But one of my former colleagues, an alarm bell rang in his head, and he thought, "I've heard this before," and, think it was four years earlier, he'd been contacted by Alan Bates, who'd had the same problems.

Then they started to build up a picture.

People having the same problems, people being told the same thing from the Post Office, which eventually led to them gathering information about four other subpostmasters and doing this first story.

But we were so worried about legal action, we didn't actually publish it for a year.

NARRATOR: This was the response from the Post Office.

MAN: The Post Office Horizon system is extremely robust.

It is regularly tested and scrutinized, and we do not have any complaints from subpostmasters.

That was an outright lie.

We knew of seven postmasters who had complained, and also, we know that computers have problems, especially complex systems.

Suddenly, subpostmasters who had problems were seeing the story, contacting each other, which then started the campaign.

♪ ♪ That's the seven from "Computer Weekly."

Then there's, uh, two that came via our website.

But where are all the others?

So we thought, let's see if we can get people together, and let's see how big the problem actually is.

Somewhere central.

Fenny... Compton.

(murmurs): Compton.

♪ ♪ BATES: We didn't know if anyone was gonna turn up, but, slowly but surely, people turned up.

♪ ♪ HAMILTON: We all sat round in a circle telling our stories, and... You almost felt embarrassed about having to say, "Oh, I'm Jo and I've been done for £36,000."

But I realized, like, "Oh, my God, we're all exactly the same."

NOEL THOMAS: That's when the stories, a jigsaw started coming together, if you know what I mean.

And we'd all had our lives completely tipped upside down.

BATES: People had been losing houses, cashing in their pensions, they'd been borrowing money off of relatives, marriages were splitting up.

HAMILTON: We all looked like we'd been in a war, and just weary with the stress that we'd been put through, and the shame of it.

BATES: It was diabolical, but that's when we knew something had to be done about it.

NOEL THOMAS: And that's when we picked Alan Bates as chairman.

That was really the start of everything, and that's where the JFSA, Justice for Subpostmasters Alliance, was born.

♪ ♪ It was like a switch got turned, and the Post Office was the enemy.

They'd gone from this trusted brand to a monster.

And it was, like, "We are gonna get them."

♪ ♪ ♪ ♪ ♪ ♪ (computer keys clacking) SUZANNE SERCOMBE: This is the view I have of him most of the time.

I mean, most mornings, this is what he's doing, and as you can see, he's still in his dressing gown.

♪ ♪ NARRATOR: For the past 20 years, Alan and his partner, Suzanne, have had their lives dominated by one thing.

BATES: The whole of this Post Office issue has turned into probably the worst unpaid full-time job you can imagine.

♪ ♪ SERCOMBE: I'm gonna do the cat, and I'll have her sitting down on the carpet here, looking up at him as if to say, "Well, when are you gonna finish?

", you know.

"When are you gonna take a break?"

BATES: Because you are hearing stories of such distress and family ruin.

So, you couldn't give up working on something like this, because it, it developed a life of its own.

And it wasn't just me.

Other people were chasing their own MPs.

♪ ♪ LORD ARBUTHNOT: The good thing about being an MP is, if you contact someone like the chairman of the Post Office and say, "I'd like to meet you to talk this through," they tend to respond.

Um, Mrs. Hamilton?

That's me.

James Arbuthnot.

Thank you for coming.

HAMILTON: He came out to the shop and met my parents.

And he was just a thoroughly decent guy.

There are two other cases in my constituency alone.

Wow, really?

It's very odd, isn't it?

I thought there's something obviously not right.

And so I went to see the then-chief executive of the Post Office, Paula Vennells.

NARRATOR: Paula Vennells was hired by the Post Office in 2007.

By 2012, she'd worked her way up to the top job, and used her in-house PR to highlight her commitment to subpostmasters.

It was Paula Vennells who suggested that what we needed was forensic accountants to go into the allegations, and we said, "That's exactly what we need.

Who would you recommend?"

♪ ♪ NARRATOR: Ron Warmington runs Second Sight.

I was head of investigations for one of the world's biggest banks for many years, and now I'm meant to be retired.

The only reason I'm not retired is because of this case.

NARRATOR: Ron's investigation was paid for by the Post Office itself.

BATES: But obviously, we had very serious concerns that it's gonna be a bit of a whitewash.

NARRATOR: So Alan and the MPs brought in their own top forensic accountant.

WARMINGTON: Kay Linnell flew at me like a tigress.

I don't doubt your paper qualifications.

I have them here in front of me.

But I see nothing to persuade me that Second Sight is remotely capable of producing a truly independent report.

Clearly suspecting that either we were hired to do a whitewash or that we'd be hopelessly incompetent.

Probably she thought both.

The involvement with the Post Office started with Jo Hamilton, my local subpostmistress.

NARRATOR: Kay volunteered to help the subpostmasters.

I had no idea how long it would take, but I knew we had a room of people who had lost everything or were losing everything, and people were still being prosecuted almost on a daily basis.

And I knew we had to do something to try and stop the tide or raise the profile.

She clearly was exactly the person we needed.

Having had that meeting with Ron and Ian, which I suspect they will remember, I was satisfied they would do an independent job.

♪ ♪ NARRATOR: Ron's team began their investigation in 2012.

At that time, the Post Office continued to prosecute subpostmasters.

UPPAL: Basically, I was told I was going to get two years in prison.

NARRATOR: In the West Midlands, Jess was convinced a faulty pinpad on her Horizon terminal had caused the shortfall.

And she pleaded not guilty to theft.

But the case dragged on for three years.

UPPAL: Went to numerous courts up and down the country.

In Wolverhampton Crown Court, the judge said, "Where's the pinpad?"

And the Post Office said, "The pinpad's been taken away for repair."

And so the judge said, "Well, if it's gone for repair, it was faulty."

And that's when it all got thrown out, basically.

NARRATOR: By then, the damage had been done.

UPPAL: The stress that we'd been through, the trauma that we'd been through, lied to, bullied, it all mounted up, and I ended up in hospital.

And I, uh, went to commit suicide.

(exhales) (voice trembling): I even tried to commit suicide in hospital.

♪ ♪ NARRATOR: Jess was so ill, the doctors decided to treat her with electroconvulsive therapy.

♪ ♪ UPPAL: All I remember is, they used to put this, like, a helmet-type thing on my head.

And the shockwaves were going through my brain.

So I had, uh, I think I had 14 treatments like that.

♪ ♪ After that, I lost all my memory.

I don't remember anything from my childhood.

I couldn't sleep unless I had sleeping tablets.

Put me on numerous medication.

(voice breaking): Which I'm still on today.

And it's all down to the Post Office.

♪ ♪ NARRATOR: During Ron's investigation, it became clear the Post Office had some serious questions to answer.

WARMINGTON: There were documents which looked extremely suspicious.

Very poor investigative processes that were directed blatantly at simply asset, recovering assets, um, by trying to get the easiest conviction possible, which generally was false accounting, using as a, as a, as a cudgel bluffing that they had a theft case.

♪ ♪ I'm pretty used to being able to detect crooks.

But when I really dug deeper, didn't find any evidence of theft at all.

♪ ♪ BATES: We didn't know whether the investigation would work.

But the very fact that they had access to Post Office's data, um, seemed quite promising.

And at that time, we did understand that Post Office did actually want to get to the truth.

I felt we were getting somewhere.

(chuckles): Little did I know how... How long the journey was gonna be.

♪ ♪ Remote access to the system was always a huge concern.

And the reason why was, it meant that someone else could be accessing your accounts on your counter in your post office, and you did not know about it.

♪ ♪ NARRATOR: When the Post Office rolled out their new computer system, every subpostmaster's computer was hardwired to a central hub.

This was located at the headquarters of the company who designed and managed Horizon, Fujitsu.

Post Office were quite adamant that no one else could ever access the systems or do anything like this at all.

And that was something that we wanted Second Sight to prove had occurred or how it had occurred.

MICHAEL RUDKIN: I went to Fujitsu headquarters with the intention of helping and, uh, looking at the system and how we accounted for bureau de change within branches.

Uh, Michael Rudkin to see George Delph.

That was the purpose of my visit.

I arrived as scheduled about 10:00 in the morning.

Cheers.

RUDKIN: Went into reception.

Mr. Rudkin-- George Delph, hi.

RUDKIN: Within a few minutes, my chaperone arrived.

I was really taken aback by the number of security doors that we had to pass through.

I was encouraged to enter into the boiler room by my chaperone.

And in doing so, I then recognized, to the right-hand side of me, there's two Horizon terminals on this workbench.

One of the guys, not happy with my presence, gets up and walks out.

My chaperone said, "This is my covert operations team and my covert operations room."

He proceeded to enter into this particular account, and he started, uh, altering figures, which, I said to him, "Is, is this real time?"

He says, "Look, I'll just prove it."

He says, "I'll alter the euro figures in this branch's accounts."

You're inside some subpostmaster's Horizon, and he doesn't know.

In total disbelief, I said, "Are you sure you can alter these figures in real time?"

And he said, "Yes."

I said, "Well, for your information..." I've been telling my members for years no one else has access to their branch accounts.

RUDKIN: "And here you are proving that you've got remote access."

At which, there was an, an immediate look of disdain on his face, and then ushered me out, and, more or less, thrown out as though I was a thief.

I said to Michael, "Your story is really, really interesting.

"But Post Office, of course, will ask for evidence "to support what you're saying.

So we need to find the visitors book."

The, the so-called visitors book that I signed, ironically, is the only visitors book that's disappeared.

WARMINGTON: "So, Michael, "you need to have a look through your email records "to see if you can find "the invitation that came through to you.

"So, get to it, Michael.

I need it, and I need it quickly."

I had a telephone conversation with Ron.

I said, "I have the evidence.

Are you in front of your computer?"

He said, "Yes."

I said, "Well I'm pressing send now"-- I did.

The reply came back, "Oh, my effing good God.

They are now going to become a hostage to fortune."

NARRATOR: The day after Michael's visit to Fujitsu, Post Office officials paid him a visit.

What come as an even greater shock was, the auditors that then came into my bedroom at 8:30 that following morning, sat on the edge of me bed, and said, "You've got a £44,000 shortage in your office."

My wife, Susan, who was managing the branch, ended up being convicted, with 300 hours community service, electronically tagged for six month.

She had to live through it, and then, and endure that experience.

♪ ♪ NARRATOR: In 2013, Second Sight published their initial findings.

With Ron's report in the public domain, Post Office management changed their approach.

LORD ARBUTHNOT: Paula Vennells rang me up to say, "What we're proposing is a mediation scheme "between the subpostmasters and the Post Office "with a senior judge as the mediator, "and that will be able to get to the bottom of all of these cases."

And I said, "Well, that sounds right and proper.

Let's go ahead with that."

♪ ♪ NARRATOR: Alan put forward 150 cases for the new scheme.

♪ ♪ BATES: The whole process, which was only meant to take x amount of months in, in total, was running into years.

You're supposed to go to mediation with a willingness to settle.

But it appeared that the Post Office was sending two lawyers who turned up and said, "You're out of time to make a claim.

It's over six years old-- forget it."

I think they were actually uncovering the real truth of what had been going on, and they didn't want to come forward with it.

ARBUTHNOT (archival): The Post Office has spent public money on a mediation scheme which they themselves have set out to sabotage.

NARRATOR: In Westminster, James Arbuthnot was working hard to keep the case in the public eye.

And they've broken their word to members of Parliament in so many different respects that it is, frankly, bewildering.

♪ ♪ If you could just introduce yourself for voice transcription purposes.

Paula Vennells, chief executive of Post Office.

NARRATOR: And then Paula was called in to face MPs.

LORD ARBUTHNOT: People do not like appearing in front of select committees because the select committee may get to the bottom of things that the witnesses may prefer that they didn't.

NARRATOR: Before the hearing, Paula Vennells asked colleagues to help clarify what she should say.

Here we go.

NARRATOR: A copy of her email has since come to light.

WARMINGTON: "Urgent: accessing Horizon.

"Dear both, Your help please in prep for the SC," the select committee hearing.

WOMAN: Is it possible to access the system remotely?

We are told it is.

That's obviously the question she's being warned she's gonna have to answer.

WOMAN: What is the true answer?

I hope that it is that we know it is not possible, and that we're able to explain why that is.

I need to say, "No, it is not possible," and that we're sure of this because of x, x, x.

This is a system that works well, and it works well for the vast majority of people.

For those it doesn't work for, we are doing our utmost.

CHAIR: I've got Nadhim, and then I've got Brian.

NARRATOR: The MPs wanted to know why the Post Office had been obstructive during Second Sight's investigation.

NADHIM ZAHAWI: Paula, why don't you give those files over?

What's the problem?

VENNELLS: Um, uh, so I, I think the, the point I want to, to pick up firstly, if I may, is that... No, just answer my-- no, answer my question first.

Why won't you give Ian Henderson those files?

Why?

We have, uh, as far as I'm aware, Mr. Zahawi, we have shared whatever information was appropriate on every single individual... That's not what Ian Henderson's saying.

It is the first time, personally, I've heard that.

You're the, you're the head of that organization.

Will you provide it, yes or no?

Simple answer.

I'm not prepared, on behalf of the Post Office...

Right.

...to give...

I've got my answer: so, you won't.

No, you won't.

No, you haven't got your answer.

You haven't heard a yes or no.

I'm simply saying that, at the moment, I'm not able to answer your question.

BATES: It was pointed out to her time after time that she was in charge and the decisions were with her.

But it just seemed to wash over her.

You miss completely... ZAHAWI: Well, this sounds like a shambles to me.

You've-- you came in here, opened by saying the system's working beautifully.

You now realize why you're in front of the committee.

Is that right?

The system...

The reason... Ian said... BATES: I just couldn't understand why, even after that, she didn't take things on board and actually be honest and own up and actually try and resolve it, which she should've done far earlier.

I am very sorry that I can't answer that, it's... HAMILTON: When I listened to the evidence from Paula Vennells...

...I realized what we were gonna be up against and just what it looks like.

I have been told that we're providing information.

It looks like it's a massive corporate cover-up.

NARRATOR: Then, a few weeks after the select committee hearing, the Post Office changed their approach again.

Post Office, uh, dynamited the mediation working group and fired everybody.

I think, at that stage, she decided it was preferable to cover up the injustice and to allow these subpostmasters to go to the wall.

And I think that's shocking.

♪ ♪ We were growing information, we were growing data.

NARRATOR: For more than ten years, Alan Bates and his team of campaigners had been carefully gathering evidence, bit by bit, against the Post Office.

LINNELL: Because we had those documents, there was a possibility then of starting some sort of litigation in the civil courts against the Post Office.

BATES: If we could find a legal firm to take it on board for us.

NEWSREADER: The headlines this morning: a report has criticized the Post Office for sacking or prosecuting subpostmasters without establishing the cause of cash shortfalls at their branches.

JAMES HARTLEY: Driving into work, normal day, into Leeds, um, and I heard a BBC, uh, radio program.

MAN (on radio): If the cash recorded by the computer system does not match up with the cash that's actually held at the branch, then they are held responsible for it.

HARTLEY: I thought to myself, uh, there may be something we could do about this to help, because it didn't sound right.

So I contacted Alan Bates.

BATES: I explained the case to him.

I showed him the type of evidence that we had at the time.

And I explained we had no money at all, but we felt there was a case there.

So, I needed to weigh up whether or not we could raise the necessary litigation funding.

HARTLEY (dramatized): There are specialist funders who are willing to take the risk, but only if there are enough of you.

HARTLEY: Because otherwise, we knew that Post Office would outspend us, and we would lose.

The only way that we were gonna be able to break through this and uncover it was a full-scale group action.

Group litigation orders are used when you've got very poor claimants and they've got enough similarity in their cases that you can literally fund one case and solve a lot of people's problems.

It was the only way, and to do that, we needed a much larger group of postmasters.

How many would you need?

(smacks lips): At least 500.

♪ ♪ NARRATOR: The meeting kicked off a nationwide search to find subpostmasters who'd had problems with Horizon.

Eventually, 555 people pursued a group litigation order against the Post Office.

BATES: The case against Post Office was very much to expose the way individuals had been mistreated in there, the lack of information that was available from Post Office, the flaws in the system they'd never owned up to, the denial that had happened, the bullying that had gone on, the abuse of individuals, the way that they'd raided people's houses, the way they'd been so high-handed, and God almighty, didn't give a damn, they're Post Office, and they can do what they want.

That's what we wanted exposing.

Alan had found the lawyers, they'd got the funding, and we were on.

NARRATOR: Alan and the Justice for Subpostmasters Alliance finally took the Post Office to court to seek financial redress.

Well, I went four days after my mum died.

She'd said to me, "Please don't stop."

And she said, "I'll be with you.

Wherever you are, I'll be with you."

And, um, yeah, four days later, I went to court.

Among Alan's group of 555 subpostmasters were people whose lives had been devastated by the Post Office.

Many had been bankrupted, prosecuted, or imprisoned.

HARTLEY: Gathering enough evidence at the beginning of the case was challenging, because Post Office had the evidence, which meant we were having to build the case with one arm tied behind our backs.

NARRATOR: But during the case, the Post Office was forced to disclose evidence they'd always claimed was irrelevant.

HARTLEY: So what we've got here is a known error log.

So what this records is the fact that there were internet problems, network problems, which were causing the error in the system, which in turn were messing up the figures and causing a financial discrepancy.

This particular example showed that the transaction that had gone wrong needed to be manually corrected.

They had teams and teams of people doing it all day long, year on year.

Quite often in litigation cases, in court cases, lawyers will say, "Well, very rarely are we ever gonna find a smoking gun."

These were smoking guns.

Not just one smoking gun, multiple smoking guns, which proved to us and proved to the court that there were multiple problems in the system.

There had been from day one when it was installed.

And that was why Post Office lost the court case.

(people applauding) NARRATOR: At the end of the court hearings, Justice Fraser delivered a 330-page judgment outlining his findings on the Horizon system.

BATES: On the day the judgment was handed down, our side was totally crammed with people.

The other side of the court, there were just two people.

They knew what was gonna happen.

They knew which way this judgment was going to land, and it did.

LORD ARBUTHNOT: Mr. Justice Fraser's, uh, Horizon issues judgment: "This approach by the Post Office has amounted, in reality, to bare assertions and denials..." "...that ignore what has actually occurred."

"It amounts to the 21st-century equivalent of maintaining that the Earth is flat."

(giggles) Good ol' Justice Fraser.

The judge said there seemed to be a culture of secrecy and excessive confidentiality within the Post Office.

(cheering) We couldn't be more happy with the judgment from the court.

Um, this has been the result of many years' work, um, to achieve justice for over 550 people.

It was overwhelming.

It was utterly, utterly damning of Post Office.

And it just vindicated everything we'd ever said about them.

The win was one of the best days of my life.

The civil justice system in the U.K. had got to the truth.

NARRATOR: But the win came at huge financial cost.

Although the Post Office agreed to pay 57-and-a-half million pounds in damages, after legal costs, the subpostmasters were left with around £20,000 each.

♪ ♪ But the civil court win did enable the subpostmasters to appeal their criminal convictions.

REPORTER: These subpostmasters have not only had their convictions quashed, but they've been exonerated by the Court of Appeal.

(cheering, applauding) I'm not a criminal anymore, I'm a victim.

(laughs) NARRATOR: To date, 93 out of 736 subpostmasters have had their names cleared.

NOEL THOMAS: The sun was shining, and I was free.

REPORTER: How do you feel, Noel?

Very happy.

At last, you could go home and tell people you were innocent.

SIAN THOMAS: That emotion, it will...

It was like lifting that big rucksack with rocks on your back for years and getting rid of it.

Thank you, all.

MAN: Let him through, please.

Thank you, all.

Let him through.

SIAN THOMAS: You know, you could just throw it away.

It was such a big, big relief, 'cause the Post Office did a lot of damage, really, to him.

SIAN THOMAS: It's something that we couldn't have fathomed that was gonna happen to him.

NOEL THOMAS: I didn't have this many people at my wedding.

(people laugh) SIAN THOMAS: But I'm seeing my dad coming back now, s... You know, bit by bit, so we're, uh, really grateful, you know, that we've had this chance to see that, 'cause not many have.

(cheering) WOMAN: Yay, well done, well done!

(applauding) UPPAL: God's got me through everything.

I just thought I wanted to bring you here to show you, as well.

I've built myself up.

I've made myself stronger.

And I want everybody to know that I wasn't a thief.

I didn't rob the Post Office, as they say.

That's what matters to me-- my name cleared.

And it needs to be told.

Our stories do need to be out there.

But it, it's not just a little group of people.

It's hundreds.

Hundreds of people have been through this.

♪ ♪ Everybody ready?

NARRATOR: A statutory inquiry has been set up to find out what went wrong.

I know who should be held to account.

I mean, it's the people who have had a very cushy lifestyle on vast quantities of money whilst they've made hundreds, if not thousands, of individuals suffer whilst knowing the real truth of what's been going on, and denying the truth to all these individuals.

Those are the people who should be held responsible.

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