Original subtitles

(dramatic music)

I'm David Wilson, emeritus professor of criminology.

And for over 30 years, I've investigated

the phenomenon of murder and what it is that might

motivate someone to kill.

Every murder case is different.

But time and again, a deadly pattern emerges

of warning signs and red flags.

In this new series, I investigate some of the UK's most

harrowing murder cases to understand how and why

these terrible crimes occur.

This is Murder UK.

(dramatic music)

In the summer of 2011, Stepping Hill Hospital in Stockport

sees a sudden, terrifying outbreak of illness.

The medical staff are immediately confronted by a series

of events that defy logic.

22 people collapse unexpectedly.

(Nazir Afzal) It was a normal month.

There are... undoubtedly, every day, every week,

people die in hospital,

even those who come in on, you know, chest infections

or something not remotely serious.

But when you've got a spate of people suffering serious harm

who've come in for relatively innocuous reasons,

you know, a chest infection or whatever,

questions are going to be asked about what's happening.

And the initial reaction at the hospital

is to seek a scientific explanation

for what's going on.

They look at monitoring equipment. Is it faulty?

Is there something going wrong with the administration

of the medicines?

(David Wilson) Then, people start to die.

(dramatic music)

(Sarah Jarvis) Of course, when people go into hospital,

almost by definition,

they are ill or about to undergo

a medical or a surgical procedure.

But many of the patients who died

were not at the end of their lives.

Many of them were relatively young.

Once is suspicious.

Twice is a little more suspicious.

A dozen times, something's up.

(Stephen Wright) My name is Stephen Wright.

I'm associate editor at The Daily Mail newspaper.

And I cover crime and investigations.

I've covered some of the biggest crime cases, both in the UK

and abroad.

Normally, I get attracted to stories which

involve some degree of scandal.

The police were called in to investigate

because people were dying.

And it was a mystery, a big mystery.

I know that from talking to my contacts

in Greater Manchester Police, such was the concern that this was out

of control, the idea was even contemplated that they'd

shut down the hospital.

(David) The scale of the crisis forces Greater Manchester Police

to call in Detective Superintendent Simon Barraclough

to lead an investigation into the unexpected collapses.

(Simon Barraclough) We didn't know why people were becoming ill.

We didn't know the source of that illness.

So, in other words, whether somebody

was actually deliberately in the hospital poisoning patients.

And what was actually happening was happening

within that hospital on two of the very busiest wards

in the hospital.

(Stephen) What stood out really about these episodes

was that people were coming in for all types of illnesses.

It wasn't a particular person or a particular age group.

(David) The police start to investigate

individual patient files.

(dramatic music)

Josephine Walsh was a 72-year-old woman.

She had suffered from a chronic lung condition,

but a treatable one, and was thought to be getting

better when she was taken ill.

(David) She's given a saline bag to help rehydrate her.

Using bags of saline to keep people hydrated are absolutely

standard practice on every ward.

There are many patients who are unable to drink, either

because they're unwell or because they're about to have

or have recently had surgery.

It is absolutely standard.

If you walk into pretty much any adult hospital ward, whether it's

a surgical or a medical one, you will see numerous patients hooked

up to intravenous bags of saline.

(David) But Josephine's saline bag doesn't offer rehydration.

Instead, she describes a terrifying feeling of sudden decline.

(Stephen) She gave a very graphic description of how she felt

she was dying, how she could not believe the symptoms

she was suffering, feeling dizzy, and her blood

sugar levels had gone way down.

The normal times that we see severe levels of what we call

hypoglycaemia, or low blood sugar, are

among people using insulin as a treatment, usually people

with type 1 diabetes.

Sometimes, people with type 2 diabetes need insulin as well.

(David) Josephine doesn't have diabetes and does not need insulin.

Mercifully, when she did come round,

someone gave her some Lucozade, something

as simple as that to get her sugar levels back up

and quite possibly save her life.

But her statement gave a really harrowing account

of what it was like, the agonising feelings

that you had as the saline drip's taking effect in her body.

(David) The medical anomaly in these cases

is the discovery of severe hypoglycaemia

in patients who aren't diabetic.

How does insulin come to be in bags of saline?

And that shifts the focus of the investigation

into a contaminated product.

We have to look at access, access not just to the patients,

but also to the bags of saline.

And that will shift the focus of the investigation away

from specific illnesses that individual patients

might have had to the contaminated product itself.

And Josephine is the first of many hypoglycaemic attacks

on wards A1 and A3.

(Sarah) Grant Misell was just 41 years old.

And he'd come in with an overdose.

Now, he was expected to make a full recovery.

And he'd just been kept in for observation.

(Stephen) When he did arrive at the hospital,

he was examined and treated with a saline drip.

Mr Misell was to suffer life-changing brain damage

as a result of that interaction.

And this very wealthy, successful man was warned

he would never be the same again.

On admission, Grant is seen by a male nurse, Victorino Chua.

His comments in the patients' notes provide a profound contradiction,

entirely dismissing Grant's critical state

and raising immediate questions about his intent.

(Donna Youngs) Grant Misell is exhibiting all the signs

of a hypoglycaemic attack, but Victorino writes up his notes

as the patient is settled, the patient is calm,

and doesn't draw attention to the clear medical emergency

in front of him.

(dramatic music)

(David) As the investigation intensifies, the chaos

on wards A1 and A3 only grows.

Stepping Hill Hospital is desperate to pinpoint

the source of the patient collapses,

but the truth remains hidden.

There was no sign of

this trend,

this very worrying trend ending,

and obviously, a situation of deep, deep concern.

I don't think, at that stage,

people in the authorities

contemplated the idea that a nurse charged with caring for people

could be setting out to cause complete mayhem.

(Donna) Over the course of the next just five weeks,

there are more than 20 incidents of people

seeming to suffer from unexplained insulin overdosing.

And in fact, there are two deaths as a result

of these incidents in that period.

(Stephen) Tracey Arden was a woman who

was 44 years of age when she was admitted to Stepping Hill

in the summer of 2011.

She was a sufferer of multiple sclerosis.

She wouldn't have had a long life expectancy.

Nevertheless, she was not expected to die that year in hospital.

(dramatic music)

(David) Shortly after Tracey's death,

another patient, Derek Weaver, follows the same pattern.

(Stephen) Weaver was in his early 80s who

suffered from a chronic lung condition

when he was admitted to hospital.

Unfortunately, in this case, because of the impact

of the low blood sugar on his body's ability to fight off

the infection, he died not directly

as a result of the low blood sugar,

but indirectly as a result of the effect

that that had on his body's ability

to fight the bacterial infection that he'd come in with.

(David) The day after Derek Weaver's death,

a nurse on ward A1 notices a critical detail.

Five weeks after this outbreak has started,

on the 11th of July, 2011,

we have a young nurse about to administer

a saline drip when she notices

that the saline appears to be foamy, frothy,

which it shouldn't be.

They immediately reported this.

And it was as a result of that

that it was discovered that that ampoule

had been tampered with.

She can smell the disinfectant type aroma

of artificial insulin.

The nurse immediately informs the senior staff.

And an investigation of all the medicines in the treatment rooms

is immediately carried out.

(David) The sense of fear that people have about what's happening

on the wards provides the killer with a great deal

of psychological satisfaction.

The killer must understand that they are the cause

of what is happening, but are unidentified.

That gives to them a sense of power, a sense of control,

and also an imperceptible sense of being unimpeachable.

And of course, what that does is feed into the killer's narcissism,

the need to be the centre of attention,

the need to be the person that everybody's talking about.

(Sarah) The medical team immediately

went on to examine other ampoules and intravenous bags

and discovered that many of them, too,

had been tampered with and contaminated, mostly with insulin.

Those bags are plastic.

And they are relatively easy,

because they're plastic, of course,

to get a needle, to inject a needle into

in order to contaminate them with something else.

(dramatic music)

The police arrive at Stepping Hill Hospital.

Their investigation, called Operation Roxburgh, begins.

The moment Operation Roxburgh was set up,

everything at the hospital changed.

CCTV was set up at the entrance.

It was set up in the treatment rooms, at the drug storage rooms.

Everybody was under constant monitoring.

(David) And more saline bags are found to have been contaminated.

On discovery of 19 contaminated saline ampoules

in the treatment resource room, CCTV is put into place.

And the medications are kept under much higher levels of security

as the police try to establish what's going on.

Clearly, there's a climate of fear and suspicion.

And it becomes apparent that there is wrongdoing going on,

that this is no longer being treated

as some kind of technical or scientific problem.

Somebody is deliberately causing harm.

After these bags have been found to be contaminated,

the police look at others.

And we discover that it's not just saline bags

that are being contaminated.

A bag of metronidazole, which is an antibiotic

used to treat severe infections, has also

been contaminated with insulin.

And another bag has been contaminated with lidocaine,

which is used as a local anaesthetic,

but which can also cause abnormal heart rhythms

and can be potentially fatal.

(Nazir) Other nurses carrying out their normal activities

were putting people at risk without any knowledge

that they were doing so.

Nurses were being accompanied by security guards

doing their job in July of 2011 because they

were so concerned about what was happening.

The whole organisation was in...

well, in real danger of falling apart.

(Sarah) Access was restricted to even intravenous saline, which

normally, you'd never think of as something

that you would need to look carefully about, that you would

need to pay close attention to.

So everybody is going to be suspecting everybody else

and worrying about the impact, not just on each other,

but, of course, also on patients.

(David) Police launch a methodical, painstaking search for clues.

They must now systematically dissect the entire operation

patient by patient, shift by shift.

The police do a meticulous and detailed cross-referencing of all

the hypoglycaemic incidents that have occurred

in the hospital and monitor the shift

patterns of more than 4,000 staff.

(Sarah) The investigating team set about looking at every episode

that they could find of hypoglycaemia, low blood sugar,

and cross-referenced all of those episodes

with which staff were on duty.

That must have been a horrible time for all the staff,

worrying whether they might come under suspicion.

(David) The police's investigation leads to one particular name,

Rebecca Leighton.

Her fingerprint is found on a saline bag

that the police suspect was contaminated.

(Nazir) Very early on in this investigation,

the police presented some evidence which gave cause

for concern sufficient enough

for her to be charged not with murder

but with causing criminal damage which endangers people's lives,

i.e. potentially damaging the saline drips.

(David) Rebecca Leighton is remanded in Styal Prison.

There was some pressure to deal with this,

from a police perspective, as early as possible.

And that meant... not cutting corners.

It meant that when they became aware, as they did,

of somebody who was perhaps involved in nothing overly

criminal, but some kind of criminal activity,

the suspicion fell on this particular person.

And then, sadly, the police's role was to try and find

as much evidence against her without thinking there might

be somebody else at work here.

(David) In arresting and prosecuting Rebecca Leighton,

you see the police almost forced into making a decision

when there simply isn't the evidence beyond a reasonable doubt

to make that prosecution.

And what does the arrest of Rebecca Leighton

do for the killer psychologically?

Well, it makes him feel unimpeachable.

It makes him feel even more powerful, even more in control.

After six weeks in prison, all charges against her are dropped.

There's no evidence she was a poisoner.

(Nazir) Thankfully, after six weeks,

I'd come to the conclusion there wasn't enough evidence

against her, dropped the case against her.

She was very vocal and later successfully

sued Greater Manchester Police.

(David) The police later pay Rebecca Leighton

53,000 pounds to settle out of court for breach

of privacy and negligence.

(Stephen) I mean, that was really a sensational development

and increased the interest level in the case,

you know, a proper crime mystery.

Who was it?

The attacker was still at large.

(Nazir) There was urgency.

And that urgency was such that, ultimately, the wrong person

was suspected initially.

(dramatic music)

(Sarah) It must have been horrible for all the staff

left behind when the colleague with whom they'd worked regularly,

and may well have liked and trusted,

was arrested.

Suddenly, they were left shaken,

but almost more shaken when it then

becomes apparent that she didn't commit these crimes

and is released.

Because the staff will then have realised that, actually,

they've spent the last six weeks still living

and working with the culprit.

A murderer has been among their midst

all that time, even when they thought they had been caught.

(dramatic music)

(David) After Rebecca's release, a quiet calm

settles over Stepping Hill.

The attacks stop, but only for a time.

(Stephen) By that time, the medical store cupboards

had a lot more security around them, which meant that

whoever it was who was believed to be contaminating medical products

wouldn't have such easy access.

Should the killer, the attacker, wish to continue their spree,

have to find a new method.

(dramatic music)

Everything seems to be getting back to normal

at Stepping Hill Hospital until the night

when Victorino Chua gets into an argument

with the daughter of one elderly patient that he's looking after.

(David) 86-year-old Maria Pawlyszyn is

admitted to Ward A3 after suffering a suspected mild heart attack.

The nurse who looked after Grant Misell is on shift,

Victorino Chua.

(Donna) Her daughter, who gets into an argument with Victorino

over the suggestion from another doctor

that her mother needs a heart monitor,

and Victorino sulkily throws a heart monitor

without a plug at the patient.

The daughter, in fury, argues with Victorino.

The next morning, her prescription

charts are found to have been altered,

and not even very well altered.

It's pretty crude.

On careful examination, it turns out that she's not the only one.

(Donna) And in fact, the prescription

charts of five other female patients

have also been clumsily altered.

(David) Altering prescription charts can be deadly.

(Sarah) In hospital, patients will have a prescription chart which

will give medications that they are to be given regularly,

along with how they're to be given, the dose they're

to be given, how often they're to be given, and so on,

and drugs which are to be given as needed, so for instance,

painkillers, which may be needed and given as required.

Those prescriptions are all checked against each other.

So if a prescription chart has been changed

and nobody notices, then the patient may well be

given something by the nurses completely unknowingly,

which could do them harm or even kill them.

Who on Earth would want to do that?

(David) What's interesting is that there is a sudden

and, for me, quite a clumsy change in MO.

You know, Chua stops using insulin

and starts to change prescription charts.

Now, that's actually quite clumsy.

It's clumsy because it's quite easy to ultimately

work out who it was that changed the prescription chart.

We could speculate that he's doing that because he feels omnipotent.

He feels as if he's never going to be uncovered.

Or we can interpret that as simply he becomes more desperate,

he becomes more desperate, and therefore is

trying anything to cover the tracks that would have

led investigators to his door.

Six elderly patients, including Maria Pawlyszyn,

are lucky to survive.

Given the severity, the matter is immediately referred to the police.

So the police are called in again.

And this time, they draw up a Venn diagram

of all the nurses on shift the night before,

all of this pointing to only one common denominator,

Victorino Chua.

(David) After emigrating from the Philippines,

Victorino Chua joined Stepping Hill Hospital in 2009.

(Stephen) Chua was born in the Philippines' capital, Manila,

in 1965.

He was one of six children born to a couple.

He had what we in the UK would regard probably

as quite a poor background.

His father had died when he was only 19 or 20.

And that had affected him badly.

But I think one of his relatives had

encouraged him to become a nurse.

And he went to a respected local nursing college,

to Metropolitan Hospital Nursing College.

And then he went to another nursing college

called the Galang Nursing College, which was a very notorious

nursing college because of the poor academic records

there and the finances.

And he did qualify as a nurse at the Galang.

And he was earning equivalent of about 3 pounds a day as a nurse.

And he was married and had two children who he was supporting.

(David) In 2002, Victorino answers a newspaper

advert to work in a UK care home.

That's not remotely unusual.

There are a huge number of nurses from the Philippines

working in the NHS.

And I have to say, having worked with many of them myself,

my experience is that the NHS would fall apart without them.

(Donna) Victorino works in a number of care homes

and seems to get on initially fairly well,

to adjust fairly well, and be well liked in these care homes.

(David) Victorino, however, is prone to falling out with people.

(Donna) I think he has that kind of superficial, gentle personality.

But underneath it all, there is a burning anger

which does come to the surface.

And we hear about him leaving care homes

in dispute when there have been arguments,

disputes with other workers.

You've got to have professionalism.

And any explosions of ill temper would be really bad for patients.

But they're also going to be extremely bad

for the morale of the team.

(dramatic music)

(David) Victorino Chua secures a job at Stepping Hill Hospital,

despite management being made aware of his volatile temper.

(Donna) He seems to be getting on well in his role as a nurse,

but even now, actually, Victorino is experiencing anger issues.

(Nazir) He did not like those who managed him.

He did not like the hospital authorities.

He felt that he should be allowed to just get on with his job.

Maybe in part, he was upset about the fact

that he wasn't being promoted, that he'd

been turned down for promotion.

And so he did not care who was held responsible for the things

that he was doing, because ultimately,

senior managers would take the flak.

(Donna) And we know that he's actually

seeing a therapist for this anger.

And there are just some bits of information that come out

from that therapeutic interaction.

(David) Victorino's therapist offers a simple outlet

for his frustration.

His therapist, fairly common practice,

recommended that in order to find an outlet

for his frustration and his anger, he writes down his feelings.

It's full of details about Victorino's feelings,

about his early life.

It's full of feelings of anger towards his colleagues.

(dramatic music)

(David) Chua comes across, to me, as one

of those people who are real grievance collectors.

He's fuelled by resentment.

He sees himself as undervalued.

He sees himself as having been overlooked for promotion.

He sees himself as much more competent than the role

that he plays within the hospital.

And grievance collectors, often, are very self-righteous.

And that self-righteousness seems, to me,

to be what fuels a lot of his behaviour within the hospital.

He's trying to extract revenge on those people

who didn't recognise his worth.

And of course, that kind of righteous slaughter

becomes the outgrowth of that resentment.

(Sarah) Now, interestingly, the people who worked with him

say that he was good to work with,

that they enjoyed working with him,

that he was friendly.

But there are reports that he was prone to violent outbursts

of temper, and particularly when his ability or his self-esteem

were challenged.

(David) I know from my own research that grievance collectors are

often prone to violent outbursts.

But, you know, violent outbursts, in themselves,

are not evidence of a crime having been committed.

And therefore, the challenge for authorities

is that they might be able to hone in on Chua,

but can they find definitive evidence that would

prove that he was the killer?

(David) Based on the evidence, police

discover that Victorino Chua is the common denominator

in all the collapses.

He's arrested at his home on January the 5th, 2012.

(Sarah) While they're there, the police search his home

and they find the bitter nurse confession, which,

frankly, was a real smoking gun.

"There's a devil inside me.

"Some of these things, I will take to my grave."

Clearly, he's talking about what he's guilty of there.

But he also talks a lot about his colleagues.

Now, some of them, he says, are OK.

But some of them, he describes as "nasty bitches."

The bitter nurse confession.

He sees himself as an angel who turned into an evil person,

but essentially, an angel.

This is a person who does not really blame himself.

He's so used to attributing blame to other people.

How many nurses write a document where they

compare themselves to the devil?

Seems to be some kind of confession

for all the incidents and murders that

have taken place in the hospital.

(David) I find the bitter nurse confession that Chua writes

a kind of fascinating piece of evidence.

It quite consciously tries to construct a narrative

about the evil inside the angel.

But it also constructs a narrative which really shows, I think,

more than anything, the narcissism that we're dealing with

in relation to Chua.

You know, the bitter nurse confession is about me, me, me.

And it's serving a purpose for him.

And that purpose is that we will always

remember that confession, as opposed

to remembering the people that he killed.

The confession is damning, but detectives

know they need ironclad forensic proof to secure a conviction.

The investigation moves to the interview room,

where Victorino Chua is brought in for questioning.

(dramatic music)

(Sarah) The police describe Victorino Chua

as a narcissistic psychopath.

Now, interestingly, psychopath is not actually a medical term.

But it's often used to describe somebody

who doesn't live within the norms of society

and who doesn't have any empathy or remorse.

It's closely linked with sociopathy.

That's otherwise known as antisocial personality disorder.

And people who have antisocial personality disorder

don't have any empathy for other people.

They don't get inside.

They don't have any feelings.

They don't care for anybody.

They only care for themselves.

They don't have a sense of right and wrong.

(David) Chua refuses to cooperate with the police.

(Nazir) A very senior police officer

was trying to persuade me to charge Chua

on the basis of what little evidence they had at that time.

And I was pushing back, saying there isn't enough evidence.

And eventually, after several hours of discussions,

I was able to persuade him that we're on the same side.

We want to convict the man who has caused these deaths and this harm.

But to charge him now prematurely would ultimately lead

to him being found not guilty.

And you would not get the justice.

And the victims would not get this justice.

Because of the huge numbers of opportunities

that he would have had to poison people

and to put their well-being at risk,

there was a vast police investigation.

It was incredibly complex.

There were almost 3,300 witness statements taken and almost

5,300 items entered into evidence.

The sheer complexity of this was mind-boggling.

(David) While the police operation continues,

journalist Stephen Wright is also investigating Victorino Chua.

(Stephen) Got a call from my office

saying that there had been what was perceived

to be a significant arrest in the Stepping Hill poisoning case.

I was asked, or told, shall I say, to get the first plane

to the Philippines the next day.

My boss wanted me to try and find out what I could about this man.

(dramatic music)

I established very soon in my inquiries,

there were very serious doubts about his qualifications

and eligibility to be a nurse.

I was able to make contact with the nursing administrator

at Galang, who still had Chua's records

from nursing college that looked like his marks had been amended.

It was highly, highly suspicious.

And police were later to form the opinion

that someone might even have sat his nursing

exams for him in the Philippines.

So as a result of those 10 days of initial inquiries in Manila,

I had really grave concerns about his qualifications, concerns

about forged references,

concerns about thieving,

which he was accused of at the hospital from patients.

I got back to the UK and was put in touch

with the senior officer in Greater Manchester Police

on the investigation.

I took the decision that it was in the public interest

for me to hand over my dossier.

(David) At the same time, the CCTV at the hospital

is also meticulously trawled by the police.

Chua is seen handling saline bags shortly before victims fall ill.

The way in which he killed people was to contaminate bags

either of saline or ampoules and to inject, usually,

insulin, into those.

(Simon) We identified 42 patients who we believed

had suffered from those low blood sugar levels.

And we started an investigation around each of those 42 patients.

Now, over the course of the time, that was distilled down

to 21 victims, who we felt we could prove to a court

were indeed poisoned.

(David) Chua engages in what I would call a kind of medical game

of Russian roulette.

You know, by tampering with the saline bags, he

allows his colleagues to use those contaminated

saline bags on their patients.

And that, of course, directs the finger of blame

away from Chua and onto his colleagues.

Nonetheless, he's still in control.

He's still powerful.

He's still manipulating.

But it also reveals what he feels about his colleagues,

which is much the same as he believed about his patients.

He's indifferent to them.

He doesn't see them as equals.

He merely sees them as props within a game

that he's playing, a game which is seeking to exact revenge

on those authorities that did not give him the promotions

that he felt he was due.

By 2015, the police and the Crown Prosecution Service

are confident in their case against Chua.

(Nazir) An inquiry like this, it's like a jigsaw puzzle.

And you have to put all the pieces together.

And once you do that, the picture becomes clear.

In this case, his presence on the ward,

his animosity towards the hospital,

his feelings about himself,

the fact that he had access to the saline drips, the fact that he was

working on those wards, the fact that he tampered with the records,

the fact that he denied responsibility, that he tried

to blame other people, you put all that together,

and you've got a picture of somebody clearly at work here.

(dramatic music)

So we had opportunity.

We had methods.

What we didn't have was him actually

doing something that brought attention to him as somebody

that was ready to harm somebody.

And these records, the tampering of these records

were, in effect, the smoking gun.

You could put on somebody's medical record

that they required three times the level of insulin

that normal people would require.

So he began to tamper with records, which

meant that he himself didn't have to administer the fatal dose

or the nearly fatal dose.

Somebody else would do the same.

(David) The court is also presented with Chua's

bitter nurse confession.

(Nazir) He argued, in his defence, that it was just the ramblings

of a sad man who was alone.

We were arguing that you can't just take the letter on its own.

You have to take the letter with everything else

that we know about the man, that this

was, in part, the motivation for this guy

and why he might have done that.

Because in presenting and prosecuting a case,

you've got to tell the jury a story.

And the one thing that was missing in this story was the why.

And the letter helped us in identifying what the why

was, why he might have done this.

(David) On the 18th of May, 2015,

following three weeks of careful deliberation,

the jury finally reaches a verdict.

Of course, in the back of your mind, you're thinking,

well, you know, you've invested an enormous amount of time in this.

You also want to ensure that, most importantly, justice is done.

There are victims and victims' families

who are looking to you for closure or some form of closure.

And it's out of your hands.

It's in the hands of 12 members of the jury

who I think were out for 11 days.

And as the days go by, whilst they're

out considering their verdict, you are less sure of yourself.

And it was an immense relief when they came

back with the guilty verdicts.

(David) Chua is found guilty of the murder of Derek Weaver

and Tracey Arden, the poisoning of 19 other patients,

and the attempted poisoning of 7 more.

(Stephen) The families of those poor victims

have had to deal with the fact that their loved ones

had their lives taken by junior nurse

with dubious qualifications who played God,

effectively, around when he decided they should die.

The judge was damning of Chua, jailing him

for a minimum of 35 years,

calling him, you know, a truly wicked person.

(David) No motive is ever established for his crimes

beyond his history of anger and resentment.

My opinion is that

he's a narcissistic psychopath

and an attention seeker

who had complex mental health issues

but that at his root was an evil, wicked person

who enjoyed and took sadistic pleasure

out of seeing people suffer agonising

deaths or near-death experiences.

(David) In my experience, serial killers don't just

stop of their own accord.

They have to be stopped.

They might be stopped by being arrested and incarcerated

for some other crimes.

Or they might be stopped because eventually, enough evidence

is found so as to convict them.

And I've got no doubt that if Victor Chua hadn't been stopped,

he would have killed again and again and again.

(Nazir) Chua was manipulative, very, very cold.

He didn't care who was harmed.

He didn't care how they were harmed

or how seriously they were harmed.

He didn't care who did the harming,

because at the end of the day,

somebody else would be attaching the saline drip

or giving the medication.

So he was prepared to put other people in harm's way.

Other people potentially could have been prosecuted

for their acts, despite being innocent.

(Stephen) How on Earth was this allowed to happen?

What mistakes were made? What blunders were made?

Why was he able to contaminate these saline bags?

Why was he able to carry out these murderous attacks?

A lot of unanswered questions.

So many issues haven't been resolved.

Questions remain unanswered.

People got away with it.

People allowed him to get a job in the NHS

when he shouldn't have done.

There hasn't been true accountability, one could argue.

(dramatic music)

(David) Although new safeguards are now in place, the tightened

regulations offer little comfort to the victims' families, whose

lives remain forever changed by Chua's murderous spree

at Stepping Hill.

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