Original subtitles

(tense 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."

(gentle music)

In 1994, in Bordesley Green in Birmingham,

Eric Lloyd is being nursed by his Filipino partner, Marie Whiston.

She's a nurse, and they live together in his home.

Eric Lloyd was eight years older than Marie.

(ominous music)

On the surface, it looks like this gentle nurse

is taking care of an ill man and looking after him.

I mean, nursing would have been just

the most natural profession for somebody with Marie's personality.

(Sarah Jarvis) I was a medical student, and I supported myself

through medical school by working as a nursing assistant

in a psychogeriatric hospital, where I was surrounded

by nurses from the Philippines.

There was a huge influx of nurses from the Philippines

around about that time.

They were incredibly devoted,

but they also worked very, very long hours.

So if Eric knew that Marie was a nurse,

he might have thought that she would be both excellent at caring

and also very, very grateful to have him

to care for her financially.

(David Wilson) Eric's medical records show that early on

in his relationship with Marie,

he suffers two mystery health scares,

both ending in a hospital emergency room.

(tense music)

Shortly after getting together with Eric,

Eric is rushed to hospital on two separate occasions,

suffering from excess insulin in his blood.

(David) Doctors are stunned.

Eric isn't diabetic,

so why would he have insulin in his system?

The only way to have too much insulin

is if you're given too much insulin.

Then your blood sugar can drop through the floor.

In the early stages, that can lead to feeling hungry,

feeling generally unwell, feeling lightheaded,

possibly having blurred vision, feeling irritable and angry.

As time goes on, with a more severe episode of hypoglycaemia,

you can come disorientated.

You can act very oddly. You can become confused.

You can collapse. You can have seizures.

And in extreme cases, it can cause abnormal heart rhythms

and even death.

Since Eric wasn't diabetic, the critical question is obvious.

Did his own partner and nurse, Marie Whiston,

deliberately inject him with insulin?

(Sarah) It is not something you take without knowing it.

You can't eat insulin.

If you take insulin in oral form,

then it doesn't get absorbed into your system,

so it needs to be given by injection.

Eric knows that that just isn't possible.

He hasn't been injecting insulin.

So what sense can he make of this?

And does he suspect Marie?

And yet he remains with her.

I think that, quite simply, Eric Lloyd needs Marie at this stage.

Two years on from his two health scares,

Eric seems to have recovered, until one day,

the inexplicable illness strikes again.

Marie was working a night shift at the hospital.

She came home from work and found Eric dead.

(door creaks)

An unexplained, unexpected death.

(David) Eric's death appears to be from natural causes,

but not everyone agrees.

One former police officer in particular, Stephanie Stevens,

begins to harbour serious doubt.

I was working as a coroner's officer

for the West Midlands Police.

If emergency services are called, if there's a sudden death,

then usually it would be the ambulance service

who arrive first. It might be the police service who arrive first,

depending on the circumstances.

If they have concerns, any concerns,

they are required to inform the coroner's service.

And the coroner's assistant will be informed.

And on this occasion, the coroner's assistant,

Stephanie Stevens, actually attended the scene.

I always remember it was a Friday.

And it was about midday.

I had a phone call from a GP who said that

one of her patients had died.

And it was unexpected.

And she obviously needed to refer it to the coroner.

I went out, went to the house in Belchers Lane,

Bordesley Green in Birmingham,

which is right opposite to Heartlands Hospital.

(David) Heartlands Hospital is where Marie works.

Marie opened the door wearing her nurse's uniform.

I went upstairs, walked past a very pretty bedroom,

which was obviously her room, walked into his bedroom,

and he was lying across the bed, very, very sparse bedroom...

just a bed and a set of drawers.

And he was dead, obviously.

So I examined the body... very, very cold.

He'd been dead for a long, long time.

And immediately, Stephanie is concerned and suspicious.

That is entirely due to Marie Whiston's reactions.

I was met by a woman dressed in a nurse's uniform.

Straight away, I was just like, this is really weird

because it was midday.

And why...why had she only just reported it?

Went downstairs to speak to her.

And I said, why are you still in your uniform?

And she said, well, I've just finished nights.

I said, this is midday.

Well, I went out to the shops.

My first impression of Marie Whiston was that

she was lying.

She was absolutely lying.

(David) But it is Marie's unusual way of grieving

that strikes Stephanie Stevens as most suspicious.

She was trying to cry, but there was no tears.

And she was looking out the corner of her eyes

to see if I was looking.

And I was looking.

And I could tell that she was lying.

Marie Whiston appeared to be very upset,

but she felt that her tears were crocodile tears.

She felt that her concern and her upset was totally false.

If you don't mind me doing this, this is what she was doing.

Trying to cry but not letting me see.

And I was just...

there's something really weird about you.

(David) What Stephanie Stevens seemed to be picking up on

is that Marie Whiston was performing grief,

almost as if she was conforming to a script,

that it wasn't authentic.

It wasn't emotional.

It wasn't grief.

You know, grief is overwhelming.

Grief is all-encompassing.

And you can't therefore switch it on or switch it off again,

depending on who's watching you and how they are

reacting to you being in grief.

So I think that's quite interesting,

that what Marie Whiston seemed to do

was perform a script, as opposed to actually

having those genuine feelings.

Marie also seems unusually anxious for Eric

to be cremated as soon as possible.

Stephanie also was very concerned that Marie Whiston

appeared obsessed with finding out when and whether

Eric could be cremated.

All she said was, I want him cremated.

I need him cremated straight away.

(Sarah) Now, of course, Stephanie Stevens,

with her experience with the coroner's office,

would have been very aware that a postmortem is impossible

once a patient has been cremated.

And, of course, there is no chance of going back

to look for further evidence.

(Stephanie Stevens) And straight away,

I'd got this instinct that she was trying to hide something.

(David) Cremation is probably the ultimate form

of destroying forensic evidence.

You are literally burning the body,

and therefore, any toxins within the body,

any physical marks on the body

are immediately going to be destroyed because, of course,

the body will be burned.

And therefore pushing in the way that Marie Whiston did

for an early cremation is, again, going to raise suspicions

in the same way that her performance of grief

had raised suspicions.

This was, frankly, another red flag.

(Sarah) So she then does some looking around.

She is suspicious enough that she looks around the scene.

She noticed that Eric had vomited, that there was a pool of vomit.

Now, this would be very unusual if a patient

had simply had a cardiac arrest.

If a death is reported to the coroner,

then it's the coroner's job...

them and their coroner's assistant...

to decide whether there are any suspicious circumstances.

If they do feel that there may be suspicious circumstances...

they don't have to have proof at this stage...

but if they feel there may be suspicious circumstances,

then firstly, they will report it to the police.

They will decide whether a forensic postmortem,

taking much, much more careful note

of what's going on, will happen.

And of course, they can decide that a death certificate,

which will allow the release of the body,

should not happen.

(Stephanie) So we took the body back to the mortuary.

Postmortem was done the very same afternoon.

(David) Despite the postmortem, Eric's sudden death

remains unexplained.

(Stephanie) The pathologist called me...

this would be now about half past 3:00...

and said I can't find a cause of death.

So I've taken stomach contents,

blood and urine, as we normally do.

And we took all those contents,

obviously, because we've got no cause of death.

Stephanie Stevens was suspicious.

And there is no question that she was going to allow this to proceed

to cremation without looking into it further,

no matter how much Marie Whiston wanted it.

There was no way I was letting it go, no way at all.

(David) Police determined they must uncover more

about the background of Marie Whiston.

Marie Whiston grew up in the Philippines,

which is an extremely poor country.

A lot of people there either live in very rural locations

or an awful lot of them in the capital of Manila,

which is very overcrowded and very, very poor.

She marries very young, which is not unusual there.

(Donna Youngs) 18-year-old Marie Whiston in the Philippines

marries a man who, unbeknownst to her,

is actually a violent alcoholic.

She then flees the Philippines and comes to the United Kingdom.

Once in England, Marie trains to become a nurse.

If you met her, she would seem the most caring and gentle of people.

To go into nursing was a fairly obvious career choice.

There was a television programme

around about that time called "Angels."

And there was very much a feeling that nurses were,

in some respect, angels.

There they were in the caring profession,

looking after other people.

It would have allowed her a very different lifestyle,

if you like, compared to what she'd had.

She wasn't dependent on anybody as she had been in the Philippines.

It would have allowed her financial independence.

And that would have been enormously important for her.

But it would also have given her social status

because of the high regard in which nurses were held.

And that would have been, I suspect, very appealing to her.

(David) Now settled in England, Marie decides to remarry.

(Donna) In 1973, Marie then meets and marries Robert Whiston.

Coming to the UK as an immigrant and fleeing

the kind of violent marriage at such a young age that she did,

she will have felt very exposed and vulnerable.

But over time and through meeting Robert,

she becomes more established.

She has children.

She goes into the nursing profession

and puts down roots in England.

(David) Serial monogamy is a survival strategy,

especially for people who feel exposed or vulnerable in some way.

And so quickly marrying one partner after another

is to give that person a sense of security, a sense of safety.

The relationship, in other words, isn't emotional.

It's transactional.

If that security no longer is forthcoming,

then that person will quickly move on to the next partner.

So serial monogamy is an interesting pattern

in how Marie Whiston behaves throughout her life.

But Marie holds a profound secret, one she's desperate

to keep away from her new husband.

They went on a holiday to the Philippines.

We don't know if he'd had any suspicions before,

but while he was there, it appears his suspicions

were very much aroused that she might still be married

to her abusive and alcoholic first husband.

(Donna) It's actually a bigamous marriage.

She remains married to the violent, alcoholic husband

in the Philippines.

The bigamy, I think, is just something

that she felt she had to do to survive,

even if that means committing bigamy.

And when Robert discovers this, things turn nasty.

She married a gentleman called Robert Whiston.

They had, I think, two children.

But eventually, the marriage broke down in rather

acrimonious circumstances.

There was a big battle over the custody of the children.

And in the end, it was Robert Whiston who was awarded

the custody of the two children.

Robert was given care and control of their children...

in other words, effectively full custody.

But I think it would have been very unusual for a father

to be given full custody,

especially when their mother was a nurse.

(David) So why does the judge refuse to grant custody

to the children's mother, Marie?

There's talk of Marie trying to set fire to Robert.

Somehow, the judge is picking up on something unstable,

erratic, untrustworthy lying beneath the apparently

placid and gentle demeanour that Marie is presenting.

And I think this is the first time

that anybody is picking up on this.

And I think it's here that we get our first indication

of the instability and volatility

of Marie's personality.

(David) In 1989, Marie makes the acquaintance

of former factory worker Eric Lloyd.

So quite quickly after her marriage to Robert has imploded,

Marie meets a car factory worker, Eric Lloyd,

who is not in the best of health.

He and she live together in his house.

Marie very easily falls into a nursing role for him.

(Christopher Hotton) Mr Lloyd had made Mrs Whiston

the beneficiary of his will.

And so if he died, then she stood to inherit

a significant sum of money.

(David) But despite being a beneficiary of Eric's will,

Marie immediately embarks on another affair.

(Christopher) Her interest in him waned,

and eventually she met a gentleman called Mr Beattie.

And at the time that Eric Lloyd died,

Mrs Whiston was, in effect, in a relationship with Mr Beattie.

This new relationship is more than just a passing fancy.

The pair are making plans to start a new life together in Canada.

In fact, she'd been off registering

her forthcoming marriage to another man.

She was aiming to elope with him or to go abroad with him

and marry him.

And of course, if she'd done that, then she would have missed out

on her inheritance from Eric.

(suspenseful music)

So while with Eric Lloyd, she was also conducting an affair

with a Mr Beattie, I think, all the while preparing for that,

looking for a means to cash in on her relationship with Eric Lloyd,

knowing that he was not very well.

(tense music)

(David) Of course, when the serial monogamy

leads to the end of a relationship, there's often a tipping point.

And sometimes that tipping point, as in this case with Eric,

would be because Marie has established that there would be

a better transactional relationship with someone else...

in this case, with Mr Beattie in Canada.

She therefore needs to get rid of Eric.

And therefore, the serial monogamy will move on yet again.

It suggests that Eric's murder was a calculated transaction

to finalise the past and fund the future.

(David) Stephanie Stevens, the coroner's officer,

is sure something's wrong.

And she's not the only one.

Eric Lloyd's family are also certain

he didn't die from natural causes.

Just a couple of days after Eric's death,

his daughter makes a dramatic accusation.

On the Monday morning, literally as I got to work,

knocking at the coroner's door was the daughter

saying, Marie Whiston, my dad's common-law wife,

I think she has killed him.

So I said, what makes you think that?

She said, well, Dad's just changed his will.

(David) Marie is the primary beneficiary of Eric's will.

Then, for an unknown reason, Eric changes his mind.

(Donna) This threatens the most fundamental thing to Marie.

Marie's survival instinct

will have been utterly kicked in by this.

To someone like Marie Whiston, to exclude her from his will

will have activated, will have triggered that survival instinct.

Having excluded her from his will, he sealed his fate.

Marie now had both the method

and the motive in her hands.

Underneath the placid demeanour, there was always a potential

to react when she needed to survive.

But now things have imploded again.

And acrimoniously, she's become something

much more strategic, much more dangerous.

She's mutated into somebody much more ruthless,

somebody who will now do anything to survive.

And I think that that's why very soon after meeting Eric Lloyd,

we see her beginning to put into play a plan

to murder him.

(David) Marie appears to have a motive,

but which method did she use?

The two mystery insulin overdoses that Eric suffered

earlier in their relationship are the key clue.

It seems very likely, given that Eric firstly

said he'd never taken insulin,

secondly, had no reason to because there's no suggestion

that he wanted to harm himself, and thirdly,

wouldn't have had easy access to insulin.

The only person who, A, had access to insulin

and, B, might have wanted to harm him is Marie.

That very much suggests that she is giving him insulin

in order either to harm him or in an attempt to kill him.

(tense music)

What my belief is...and this is what I told the coroner...

is that she'd come home from working her night shift.

She'd gone out to dispose of the syringe,

which we never found.

I actually went around the bins in Bordesley Green

looking for the syringe, but I never found it.

There was a pond.

And I even went out into the pond and searched the pond

to see if there was anything in the pond.

(Sarah) Nurses are extremely used to giving injections.

Marie Whiston was an experienced nurse.

While she was working on wards, she would almost certainly

have had patients with type 1 diabetes.

And she would have been giving them injections

if they were incapable of doing it themselves,

of giving them injections of insulin.

So there's no question she knew about the effect

that insulin could have.

She knew about the danger of giving too much.

(tense music)

If you give a person who's got a normal pancreas

producing a normal amount of insulin

extra insulin from outside by way of an injection,

then that can and will reduce dramatically

the amount of sugar in the blood.

And that can lead to death, for example, by heart failure.

(suspenseful music)

In fact, as recently as 2020,

there was a review in a medical journal

which was sort of asking the question...

wasn't saying, but was asking the question,

is insulin the perfect murder weapon?

But at this stage, Eric's postmortem

shows no signs of foul play.

The police are not convinced Marie is a suspect.

(Stephanie) When I informed the police, the police were,

no, I don't think there's any evidence.

The coroner backed me, and he said, actually said to me,

as a coroner's officer, Stephanie, I trust you.

Go with your instincts and do what you need to do.

(David) Stephanie returns to Eric's house,

determined to find physical proof.

(Stephanie) That's when I went back,

and I cut the carpet up where he'd been sick.

Found a Medi-Swab, which is what you use to pre-inject someone.

Eric was not a man who was taking injections of insulin

or anything else, to her knowledge,

and therefore, there was no reason for pre-injection swabs

to be in the place if it wasn't that somebody else

had been giving him an injection.

As forensic tests are carried out on the vomit-stained carpet,

Marie offers up another explanation for Eric's death...

suicide.

(Sarah) Marie Whiston was not about to admit murder straight away.

She perhaps does the obvious when she suspects maybe

that there isn't going to be a cremation,

that the insulin might be found.

She decides to claim that Eric has committed suicide, which would,

of course, be a way of explaining how he had

such high levels of insulin in his body

if she hadn't given it to him.

(David) When Whiston realises that she can't refute the evidence

in relation to the presence of insulin in Eric's bloodstream,

she quite clearly tries to manipulate the narrative once more.

She tries to box clever without admitting her own guilt.

And that's why she starts to claim that Eric committed suicide.

She recognises that the police have evidence

in relation to the insulin,

and she's simply fabricating a narrative to explain

why the insulin might be there.

With the police still unconvinced, it falls to Stephanie

to prove that Eric Lloyd died from an insulin overdose.

Now, the best way to show whether you've been given insulin

or whether you've produced it naturally

is to use something called C-peptide,

which is a natural chemical produced by your body

when it's producing insulin.

In the ordinary person, where they've got insulin in their blood

that's come from their own pancreas,

there is a known relationship between the amount of insulin

and the amount of C-peptide.

And if they are... those two substances

are in the normal relationship, well, that demonstrates

that the pancreas is responsible for the insulin

that's in the blood.

Where a person is injected with insulin,

that injection does not contain any C-peptide.

The manufacturers of insulin don't put C-peptide in it

because it's not a substance that has any known use to the body.

(David) The science is clear.

If Eric's blood shows insulin without corresponding C-peptides,

it proves the insulin was injected.

But there's a major problem.

The blood samples collected from Eric during his postmortem

are compromised and may be unusable.

The problem was that they weren't acceptable as evidence

because the samples were too damaged.

(Christopher) Pathologists took two blood samples

at the initial postmortem, but by the time

those samples came to be examined, they had deteriorated.

What happens is, when somebody dies, the blood coagulates.

So when we were trying to test for what

we suspected was an insulin overdose...

bear in mind, Eric Lloyd, the deceased, wasn't a diabetic...

we couldn't test the blood.

(Christopher) The red blood cells within the blood had broken down.

And so the prosecution said that blood really

could give no reliable information so far as the presence of insulin.

(David) With the blood samples compromised,

Stephanie needs a plan B.

Eric Lloyd's first postmortem was inconclusive,

but Stephanie Stevens was not prepared to give up.

He had a second postmortem.

(Peter Acland) I first became involved with the case

of Eric Lloyd through the coroner's office.

I knew Stephanie quite well.

I go into the coroner's office most days of the week.

And she seemed to have an instinct about the case

that something wasn't quite right.

There had already been a first postmortem

as a general, ordinary, so-called coroner's case,

where a colleague of mine had made a preliminary examination.

And his findings were inconclusive.

It had already been some increasing suspicion

about the case was developing

through Stephanie Stevens' concerns,

and therefore it was felt that the home office pathologist

should have another look at the body.

(David) To bring a case against Marie,

police must prove Eric Lloyd died from an insulin injection.

But there are no signs of a struggle,

nor any obvious needle marks on Eric's body.

I was able to really confirm that

there was no obvious external injuries.

There was a bruise on the thigh, which possibly may have been

related to a needle mark but could have occurred

through any other trivial incident.

Methods of estimating insulin are particularly difficult

in blood and urine, especially urine at the time.

So again, that was difficult.

We were struggling, really, to try and prove that...

or disprove that Mr Lloyd had had an overdose of insulin.

(Stephanie) We couldn't test the blood,

so the coroner said, well, let's try something else.

So this is the first time ever in history

that we decided to test the urine.

Looking at both the insulin and his C-peptide level.

The problem was that the samples were so damaged

that they couldn't be used in evidence.

Now, that left the scientists, the investigators,

with only one choice, which was to turn to the urine samples.

(Christopher) But what they did was to look at two urine samples

that had been taken at the initial postmortem,

but nobody had ever tested urine before

for the presence of insulin and C-peptide.

Ordinarily, you don't need to.

You just use blood.

(tense music)

With the critical blood evidence ruined,

investigators are forced to look beyond

conventional forensic methods.

(Sarah) So what they did was to compare

those urine samples with lots of other deceased people.

And they treated them blind without anybody

knowing which sample was which.

And they were able to identify which one had very high levels

of insulin and not of C-peptide,

which suggests that it was an insulin injection.

(Peter) The Central Mortuary in Birmingham,

they would be doing something like 6 to 10 autopsies a day.

So there was the opportunity to take blood and urine samples.

They weren't taking any tissue.

These were materials that would have been...gone to waste anyway.

(suspenseful music)

The painstaking work takes a full year as samples are collected

and a new technique is developed.

(Stephanie) For 12 months, I collected over 100 urine samples

to test for insulin.

And in all those 100, only 2 came back as positive.

And they were the only two people that actually were diabetics.

And they really developed a new science of examining urine samples

in this way and establishing that there was a relationship

between the amount of insulin and the amount of C-peptide in urine,

which could demonstrate that a person had been given

something from outside the body.

(David) Experts come to a final conclusion:

Eric Lloyd died from a lethal overdose of insulin.

It was as a result of that

that they were able to charge Marie Whiston.

But will the controversial technique be enough to convict

Marie Whiston of murder?

This science was very controversial.

A lot of experts gave evidence at trial.

And it was hotly contested that this science was reliable.

If the science isn't 100% reliable,

the prosecution needs compelling circumstantial evidence.

(Christopher) Unfortunately for Mrs Whiston,

the prosecution case did not rest solely on scientific evidence.

There was a lot of other circumstantial evidence

which the prosecution contended supported their scientific case.

(David) Investigators begin to delve deeper

into Marie Whiston's past.

Perhaps most significantly from the prosecution's point of view,

during the course of the divorce proceedings

from Mr Whiston, which had taken place many years before,

Mr Whiston had sworn an affidavit.

(Sarah) Marie's ex-husband said that not only had she threatened

to kill him in the past, but that she had threatened

to do it with insulin and that, as a nurse,

she knew how to do it.

(David) The ex-husband's affidavit really is a game changer,

both in terms of the investigation and in terms of the court case,

because what it demonstrates is that this is premeditated.

The ex-husband said that Marie had threatened him by injecting him

with insulin, which, of course, happens in this case,

and that the injection would be in a pretty

obscure place between the toes.

It's almost an open-and-shut case

because of what her ex-husband says.

He had set out in writing in a document that had been submitted

to the court at the time, 1988, an allegation

that Mrs Whiston had threatened to kill him

by injecting him with insulin...

(tense music)

And that she would do so by injecting him between the toes

where an injection site would not be discovered.

So here was this allegation, which was made many, many years before,

which was extremely damaging to Mrs Whiston's credibility.

It was, on the face of it, an extraordinary coincidence

that many years ago, she should make such a threat

and then years later, in respect of a different man,

there should be compelling scientific evidence

that that was exactly the way in which he had been killed.

(David) Analysis of the vomit-stained carpet

also reveals some damning evidence.

It's highly unlikely that Eric Lloyd, who, from the sound of it,

already had great suspicions of his wife,

was going to let her inject him without knowing exactly

what was going on, and to inject him with a drug

which he must have known

could not possibly be for the benefit of his health.

So it's perhaps no surprise that when Stephanie Stevens arranged

for the vomit on the carpet to be examined,

it was found to contain sedatives,

which almost certainly Marie Whiston had given him

to render him unconscious.

That then allowed her to inject the insulin freely.

Whiston's trial gets underway at Birmingham Crown Court,

the culmination of three years of painstaking work.

It was a very long and difficult period for Mrs Whiston.

And when the police interviewed Mrs Whiston after the death

of Mr Lloyd, she told lies about her relationship with Mr Beattie

and tried to cover it up.

(Sarah) As the investigation went on,

more suspicious lies and other circumstances came to light.

For one thing, Marie claimed that she'd been working a night shift.

Now, that gives her the aura of being very caring.

I've been off caring for patients.

I came home and found my husband dead.

In fact, she'd been off registering

her forthcoming marriage to another man.

She was aiming to elope with him or to go abroad with him

and marry him.

And of course, if she'd done that, then she would have missed out

on her inheritance from Eric.

She was just lying.

I could just tell she was lying the whole time.

(Sarah) There's no question that Marie believed that

her expertise as a nurse would allow her to get away with murder.

It's ironic that, in fact, it was her behaviour

when Eric was found

which finally resulted in her being found out.

It was only because she was so keen to get away with murder

and to have Eric cremated that Stephanie Stevens,

the coroner's assistant, was so suspicious of her.

And it was as a result of that that a series of investigations

was set in place, which resulted in her being convicted.

The jury returns its verdict.

Marie Whiston is found guilty of murder.

She actually stood up and shouted that I was a bitch

because I'd found her guilty.

But it was just her evil,

evil behaviour

that I knew that she was guilty.

(Donna) Marie murders Eric actually by injecting him

with an excessive amount of insulin,

causing a death which could very easily

have been written off as being the result of natural causes.

Now, there's a sophistication to that,

but actually, it's a medical sophistication.

It's a sophistication that's born out of her medical knowledge.

(David) Marie Whiston is sentenced to life in prison

with a recommendation that she serve a minimum of 16 years.

(Stephanie) I really didn't think we would get a conviction

because I didn't have all that much evidence.

But the jury convicted her on my evidence

and the fact that she was just guilty.

(David) On appeal in 2000, Marie Whiston's sentence

is reduced by two years.

Proving to be a model inmate, she soon earns her parole.

I believe that Stephanie Stevens, the coroner's assistant,

deserves more credit than perhaps anybody else

in bringing Marie Whiston to justice.

(Peter) I think Stephanie's involvement in this case

and her suspicions were vital in pursuing the end result.

(tense music)

Eric became almost a part of my family

because I was just so convinced that a wrong had been done,

and I needed to undo that wrong.

She was such a wicked woman.

(David) Of course, the real hero in this case is Stephanie Stevens.

You know, Stephanie Stevens saw Marie Whiston's mask slip

and was not prepared to let that go.

And because of her determination to find out the truth,

a calculated killer was brought to justice.

(dramatic music)

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