Original subtitles

(Richard Shepherd) When a murder is committed,

it's always a race against time to find the truth,

to separate fact from fiction, to catch the killer,

and to make sure that justice is served.

But what happens when the truth vanishes with the victim?

I'm Dr Richard Shepherd, and I've spent

my entire career as a forensic pathologist,

performing nearly 23,000 autopsies.

I've learned that the dead don't hide the truth,

and they never lie.

Through me, you'll be hearing directly from the victim.

With the aid of a state-of-the-art laboratory,

using ground-breaking technology,

I'll be investigating a series of intriguing crimes

where, from the victims' bodies,

are revealed to you the truth behind these murders.

(camera shutter snapping)

-(touch tones beeping) -(line ringing)

(Dispatcher) Good morning, Dorset Police.

On the 17th of June, 2013, Dorset Police

pay a welfare visit to a flat in Bournemouth.

It's the home of taxi driver William Spiller,

who hasn't been seen for some time.

And there, they make a gruesome discovery.

(sonar beeping)

(touch tones beeping) (line rings)

Dorset Police receive a phone call from a woman

who says she's concerned.

She's had no contact with her boyfriend for some weeks now.

The problem the police have in relation to a phone call

like that is that they're both adults.

They're both grown-ups.

These are not uncommon things to happen.

If, as an adult, you don't want to contact somebody or call them,

then you're perfectly entitled to do that.

It's a very difficult situation for the police to deal with.

William's girlfriend hadn't heard from him for quite a while.

And obviously, she was worried.

Something didn't seem right.

And the neighbours also alerted them.

They're reporting there are flies -

dead flies, flies everywhere swarming - and a smell.

The police or a social services-type organisation

must go and look.

Because, you know, there are welfare concerns.

(Brian Hook) The woman had been receiving

texts and messages via the phone

but had never actually spoken to the boyfriend.

And that was unusual.

And at that point, I think Dorset Police

were quite right to decide

that they would go and check on the person's welfare,

which is basically to go knock on the door

and say, are you OK?

(knocking)

They enter the block of flats.

And as they approach the front door,

they are aware of an odour, a musty smell.

They force entry into the flat.

(door clicks open)

The smell was coming from the bedroom,

and there discovered this absolutely horrific scene.

(Brian) Any experienced officer would tell you

once you've witnessed that odour of decomposition,

you will never forget it.

There's a TV in the bedroom, and the TV is on a makeshift table

made of four plastic boxes.

And it's obvious to them, because of the infestation and the smell,

that they contained remains of some sort.

When the police smelt this and saw all the flies

around these plastic boxes, which are clear,

so they would have seen these body parts.

A further search is made of the flat.

And in a filing cabinet, they find a box.

When they open up that box to see what the contents is,

their worst fears are realised.

They discover it's a human head,

an absolutely horrific find

for the officers that go there initially

to find human remains that have been dismembered.

(Jane Carter Woodrow) It must have been so traumatic for the police

to deal with in that investigation.

Imagine that the forensic scientists or the detectives that

came on after would have been very surprised

by the head in the filing cabinet.

So this particularly grisly murder would have certainly

affected, you know, some of the police in terms of trauma

that they may have suffered afterwards

from dealing with the case.

(Brian) At this point, the officers withdraw.

The flat is cordoned off.

And obviously, detective branch is informed

and a homicide investigation is commenced.

(Kevin Browne) It was immediately clear,

from the way the body parts had been stored, that this

was not typical of a murder scene.

It would be unusual for the police to find something so ordered

and something so obvious.

I mean, usually, if someone is dismembering a body,

it's to conceal it, not to use it as a table for the TV.

So the police would have been very confused about why

has this person gone to so much time

to put a body in boxes

and then just to leave it there for it to be discovered.

So, in this case, this isn't about concealment.

This is about order.

The evidential trail starts right away.

This is actually a very complex crime scene,

even down to some of the things that perhaps might not be obvious.

Do all the body parts belong to the same body, is the first thing,

or are we looking for other victims?

As a pathologist, when I'm faced with multiple body parts,

the first thing I must do is make sure they

all belong to the same person.

We could possibly be dealing with a serial killer.

But in this case, there was a torso, a head, arms and legs,

all neatly severed through the joints

and stacked in plastic boxes.

They did all fit together.

And DNA testing confirmed they all belonged to the same person.

This was the body of a white man in his 40s who was large.

He was around 20-plus stone.

And the cuts through the bone were not

those of an expert, which suggested he'd been dismembered

using some kind of saw.

Certainly, the cuts weren't smooth or made with surgical tools.

But who was it?

One of the most important things in a situation like this,

you have to identify the victim.

That is of paramount importance.

The dismembered body was in such a state of decay,

there was very little left to identify the remains.

But what we did have was his teeth.

The inner soft tissue of the tooth is covered by a layer of enamel,

which is a very, very hard substance,

capable of withstanding incredibly high temperatures

and can sometimes last for hundreds of years after death.

Comparing the teeth with dental records

confirmed that this was 48-year-old taxi driver William Spiller.

(Brian) William was known locally as a gentle giant.

He's a fun-loving, humorous man that was known to a lot of people.

William was in a long-term relationship

with a woman called Glenys.

It was her that had called the police initially.

(Jane) William was a taxi driver.

He seemed very popular where he lived down in Bournemouth.

He was also a doorman at one time.

He loved playing snooker.

He did all the sort of usual things.

He had a caravan at the beach, and he'd go down there.

And he was also a father.

(Richard) William had a 27-year-old son, Nathan Robinson,

who spent his childhood growing up in the Midlands with his mother

before moving to Bournemouth to be with his dad.

(Brian) Nathan studied at Aberystwyth University.

He has a degree in mathematics.

And, at one point, he was considering

doing a master's degree.

(Jane) Nathan had just finished a degree,

graduated from Aberystwyth.

He'd gone to live down in Bournemouth.

He didn't actually have a job at that time,

but the two were living together.

(Brian) It was fairly obvious, when William was found,

that nobody had been in the flat for some time.

However, Nathan had lived with William for some years.

So where is Nathan now?

Nathan falls into two camps.

He's either in the suspect's camp or the victim's.

He could be either at this point.

If Nathan is a suspect or a victim, what's imperative,

regardless of which camp he's in,

we need to find him as a matter of urgency.

In a quiet cul-de-sac in Bournemouth,

police have launched a murder investigation after finding

the dismembered body of taxi driver William Spiller

neatly packed in storage boxes.

There was a torso, a head, arms and legs,

all neatly severed through the joints

and stacked in plastic boxes.

The dismembered body was in such a state of decay,

there was very little left to identify the remains.

But dental records confirmed this was 48-year-old William Spiller.

William shared his flat with his 26-year-old son, Nathan Robinson.

(Brian) Nathan's not there.

From the investigative perspective, why is he not there?

Nathan now has a foot in two potential boxes here.

He's either a suspect.

He could be a victim.

We need to find out which one he's in.

(Richard) Police launched a countrywide search

for William's son.

William's body was dismembered and badly decomposed,

but could it still tell us something

about what had happened to him in those moments before he died?

He was found to have a number of stab

and slash wounds all over his body.

If we look at the torso, we can see the spine and the ribs that

protect the vital internal organs.

But if we look at just the soft tissue of the torso,

we can see that the wounds are superficial.

They cut through the skin and the underlying muscle only.

They go nowhere near penetrating through the ribs

and into the vital organs.

And that's really important because it tells us

that the weapon used to cause these injuries

is very sharp but also very shallow.

During the search of the flat, police seize

a Stanley knife - a box cutter - a saw, and a hacksaw.

(Richard) While the Stanley knife was the likely weapon used

to inflict soft tissue wounds on William,

these injuries alone weren't enough to have caused William's death.

But there was something else his body

told us about this brutal attack.

Often, at postmortem, it's not what you see but what you don't see

that can become important.

As we look at William's arms, I can see there are

no slash wounds to his lower arms.

And wounds like that are caused when someone raises

their hand to defend themselves.

They're called defensive injuries.

And the lack of those defensive injuries in this case

suggests to me that this was a sudden attack

and that William was taken by surprise.

So there's no defensive wounds on the body.

And you're talking about a man as big as William,

who is 20 stone and 6'4".

So what you're looking at here is a surprise attack or an attack

by somebody he actually trusted.

And there was no time, obviously, for William to defend himself.

(Kevin) When the police attend any homicide

in a domestic environment, one of their suspicions

is an immediate family member, because, unfortunately,

40% of all homicides actually are domestic homicides

in the home by relatives.

It's actually more common than you think.

And people are more at risk sometimes

from people they know than strangers.

And so, therefore, the police would first

investigate the immediate family members for a motive,

for potential harm to each other.

And they would suspect a domestic argument

that had gone too far, etc.

However, they would have been shocked by the fact there was...

that this body had been dismembered and ordered into boxes

and left there in the apartment in such an ordered way,

because that sort of approach to a body

is very unusual in a family murder or domestic murder.

(Richard) The police investigation continued

to focus on Nathan Robinson, and detectives

began to build a picture of his relationship with his father.

When the police were searching the flat

looking for evidence, one of the things they found

was an IOU note from Nathan to William

for an absolutely staggering sum -

36,000 pounds.

That is just unbelievable.

Nathan doesn't have a job.

And William is, effectively, funding Nathan's lifestyle.

(Jane) There seemed to be an issue of money between them.

Nathan was certainly seeing, in his father, a cash cow.

He owed his father a lot of money.

And if he needed anything, he would go to his father.

He didn't actually have a job,

although he did have a good degree.

He seemed to depend on his father for money,

and the relationship seemed pretty heavily biased that way.

(Brian) There were obviously problems within the relationship,

and a lot of this stems about money.

William lent Nathan some money so that he

could go on holiday to Thailand.

The understanding was that that money

would be paid back to William, but that never happened.

And the problem arose, because William now

didn't have that money, he was unable to pay

the insurance for his taxi.

It's his livelihood. That's how he makes his living.

Nathan wasn't in education.

So the father's expectation would be that he should support

himself through being employed.

And of course, there would have been

a disappointment for the father if that didn't happen.

So that would have created conflict.

(Richard) Police inquiries with friends and family

revealed that Nathan and his father repeatedly clashed over money.

Do you expect me to subsidise you for the rest of your life,

was one of the remarks that was heard by a neighbour

during one of their arguments.

(Jane) Money can be a source of conflict

in a relationship within a family.

It certainly can be.

There was a conflict between them about money,

and that seemed to escalate over time.

(Richard) As work continued on tracking Nathan down,

detectives needed to establish a timeline

of events around William's death.

The time when that person might have died is paramount

because it will direct your investigation.

It will also give you a window of when that person died.

You get that, you know where to start your inquiries.

(Richard) Pinpointing an exact time of death was difficult,

but the hatched flies and state of decay

suggested William's body had been in the flat for around four weeks.

There was confirmation from Glenys about contact she had

and contact she then didn't have with the victim.

And that period of time is narrowed down

as to when it's highly likely,

most likely that William was killed.

(Richard) A phone call from a neighbour

corroborated this time frame.

-(touch tones beeping) -(line ringing)

(Dispatcher) Good morning, Dorset Police.

(Richard) The neighbour went on to say he'd heard

a commotion and William calling out to phone for an ambulance

on the night of the 16th of May.

With a rough time of death, the investigation

could pick up speed and hone in on a potential suspect.

Part of the investigative process, the victim

is going to be lifestyled.

Where do they work? What hours do they work?

Who are their friends? Where do they frequent?

Where might they be expected to be at any particular time?

Because that's where the paths of our victim and our suspect

or suspects may well have crossed.

There's a huge amount of work to do.

We all leave a pattern wherever we go.

Going into places, in buying things,

you're using cards, credit cards, debit cards, even cash.

One of the main investigative strands these days -

closed-circuit TV.

Hundreds of hours of CCTV is seized and looked at.

On that CCTV, we see Nathan.

Nathan is at the railway station.

Nathan is seen buying a ticket to travel to Scotland.

(Richard) This trip to Glasgow in Scotland happened

on the 17th of May, the day after a neighbour reported

a commotion at William's flat.

It made Nathan the prime suspect.

But with no criminal record, lots of friends,

and no concrete evidence, he seemed an unlikely murderer.

Police continued to investigate.

(Brian) Now that we know where Nathan has gone,

crucial evidence is being gathered in Scotland.

We need to know his movements, where he's been, who he's seen,

and what he's actually doing in Scotland.

His friends said that he was being extravagant.

He was buying them meals.

He was staying in expensive hotels.

He treats his friends. He's buying drinks.

He's buying food.

You see this largesse.

You see he's trying to impress his friends.

He has a definite sense of... in my opinion, a definite sense

of entitlement about him.

He feels this is his right.

He's there showing off.

Question is, where does this money come from?

(Jane) But we know that he doesn't have any money.

He doesn't have a job.

And his father didn't want to give him any more money.

You can only assume that he's taken his father's money.

After leaving Scotland, Nathan's spending spree continues.

He goes to see his mother.

He takes her on an expensive spa weekend in a hotel.

When he goes down to Birmingham, when he takes his mother out,

again, look at me, I'm the business.

He is the centre of his world, totally egocentric.

But he wants admiration, which you always see in narcissists.

In the four weeks since leaving Bournemouth,

Nathan had spent over 8,000 pounds.

(glasses clink)

(Richard) So did Nathan murder his father for money?

(Kevin) He used his father's money to an extreme,

spending a lot of money in a weekend.

That may tell me that he was half expecting to be caught

and he was having a big splash before he got caught.

(Brian) Police eventually track Nathan down,

and they arrest him on suspicion of being

involved in the murder of William.

His remark when he's arrested is, is this a joke?

After William Spiller's body was discovered

carefully dismembered and neatly packed in storage boxes,

police arrested their prime suspect,

his 26-year-old son, Nathan Robinson.

William's body had been slashed with a knife,

but there were no defensive wounds,

suggesting a surprise attack by someone in the home.

Shortly after the murder, Nathan had

gone on a spending spree in Scotland and Birmingham

with his father's money.

Well, it seemed that after he'd cleaned up

and he'd ordered the flat in the way that he did

that he couldn't remain there.

He needed to leave the flat and go away to Scotland,

to Glasgow, to see friends.

And so obviously, the environment of his father being there

was impacting on him, that he couldn't stay there the weekend.

Police eventually track Nathan down,

and they arrest him on suspicion of being

involved in the murder of William.

His remark when he's arrested is, is this a joke?

It's a strange response for somebody that's been arrested

for such a serious offence.

I've experienced silence.

I've experienced anger.

I've experienced confusion.

But that response is strange.

I think it's the response of somebody in denial,

and certainly he's going to be denying any involvement.

And what they now want to know

is, how much do the police know?

In other words, how much evidence have

you got that I'm involved in this?

(Jane) This is classical of narcissism.

They don't expect to get caught.

They're very arrogant.

No way is this anything to do with me.

It's very casual denial.

He wants to elicit a response from the arresting officers.

He wants them to carry on talking.

He wants them to say something back,

even if it's just, no, it's not a joke, mate.

He's now entered a conversation that he has started.

That's the start of him trying to control.

(Richard) Nathan claimed he was innocent of his father's

murder, but William's body would reveal more answers

about what happened the night he was killed.

It's the job of the forensic pathologist to determine

what was the fatal injury.

There were knife wounds all over William's body.

But critically, there were also injuries to his neck.

The neck is where there are some major blood vessels.

And you can see them here.

In red is the carotid artery, which carries blood

from the heart up to the brain, and the jugular veins,

which carry blood back to the heart.

Some of these blood vessels are protected

beneath this big muscle of the neck, the sternomastoid muscle.

But there's one blood vessel here, one branch of the jugular vein,

that sits on top of this muscle.

And if it's cut, it's going to bleed torrentially

and is likely to cause death very quickly

without immediate medical assistance.

William Spiller's neck was severed in this place,

an injury that would have produced a considerable amount of blood.

Cutting up the body would create even more blood.

But when police first discovered William,

the flat didn't look like a crime scene.

(Brian) One of the things that was noticed

was that the flat was very clean.

In other words, if somebody is dismembered at that flat,

you would expect there to be blood staining, blood spattering,

a whole array of things.

If you dismember somebody, it's very difficult

to clean up afterwards.

It takes quite a considerable amount of effort.

One of the things that the police discovered afterwards was that

the neighbour had complained to Nathan

that he had a pink liquid coming down the wall in his bathroom.

The neighbour came upstairs to enquire what that was,

to report it to him, and he immediately covered for that.

The neighbour said he's very cool, calm, and collected.

(Richard) Nathan claimed he had spilled red wine.

(Brian) Nathan didn't bat an eyelid

and was absolutely normal in explaining why that

was happening to the neighbour.

(Kevin) The pink fluid was probably

a mixture of bleach and blood.

(Richard) Armed with this information, detectives homed in

on the CCTV that captured Nathan's movements

around the time of the murder.

He goes out and he buys steam cleaning equipment.

He actually buys two steam cleaners.

There's a lot of evidence to indicate that Nathan is,

in fact, the killer of his father.

(Richard) And a forensic sweep of the flat

revealed critical evidence that the killer hoped to have washed away.

Just because you clean up blood

doesn't mean to say it's not still there.

So it might look clean, but it's not.

From the investigative process of using a liquid -

be it bleach, be it soapy water -

to try and get rid of bloodstains, what you're actually doing

is spreading it.

That stain that was 6 inches around, when you dilute it,

now it becomes 12 inches, 14 inches, 24 inches.

And what you're actually doing is moving the blood

into the cracks and the crevices where

you might not be able to see it,

but, forensically, we can find it.

Cutting up a body, especially in a domestic environment

rather than a clinical environment will make a lot of mess.

To systematically go through and clean that up,

it shows a level of not thinking about what has happened and just

getting on with the job and thinking about it as a task -

a cleaning task - rather than what it represents.

This was just something that had to be cleaned up and ordered,

which he did meticulously and very carefully.

So obviously, this to him was just a task needed to be done.

(Jane) So he's completely in control of what he was doing.

You know, there was no sort of lost touch with reality.

He knew what he'd done, knew what he was going to do.

He was going to try and cover for himself

to get away with this murder.

(Richard) Nathan also spun a web of lies

to make it look as if his father was still alive.

After William's death, Nathan goes to a huge amount of effort

to cover up the fact that he's dead.

So he didn't want that murder discovered.

He had the foresight to make sure that nobody would

be calling round for a while.

(bell dings)

(Brian) He pays the rent for the flat a month in advance,

so nobody's going to come knocking on the door.

He actually used his father's phone to communicate

with William's girlfriend, Glenys, to convince her

that he's still alive.

She'd had some text messages.

And those that she'd had, she didn't actually think

sounded quite right because she knew that William

would be in touch with her.

(Brian) He sends messages saying that

William's gone to the Midlands

because one of his friends is dying

and he wants to be with him.

You know, a terribly cruel thing to do.

(Richard) And when Glenys first

tried to report William missing to the police,

Nathan called them with his own version of events.

(line rings)

He's actually explaining away why his father is not being seen,

and all the time he knows exactly where his father is.

Just a cold, callous,

calculating thing to do.

I think that Nathan is looking for excuses.

He knows the evidence that's against him, it's overwhelming.

And he is trying every single avenue to get out of it.

(Richard) But he'd reached the end of the road.

On the 18th of June, 2013, Nathan Robinson

was arrested and later charged with the murder

of his father, William, the unlawful disposal

of human remains, and theft.

(Kevin) What we understand by patricide,

when a son or daughter kills a parent,

is that the relationship between the son and the father

is detached and possible hatred between each other.

There must have been a level of conflict in the past.

And indeed, what we find, in this case,

that it was so extreme that he committed murder, patricide.

(Brian) There is a link and a bond

that we all have with our family, which is close.

And the breaking of that bond almost feels like sacrilege.

(Jane) Nathan was a very cold, calculated killer.

And he certainly never expected to get caught.

The evidence that's against him, to be quite frank,

it's overwhelming.

(Richard) The police were confident they had their man.

But in court, Nathan Robinson denied murder on the grounds

of diminished responsibility.

And what that means is that he is saying to the court

and wants to prove to the court, he actually

didn't know what he was doing at the time

because he had no mental faculties that enabled him

to know what he was doing at all.

(Richard) But was there a reason why he did it?

During the court case, Nathan makes

an absolutely explosive claim.

He'd forgotten about it.

And suddenly, it came back to him.

(sonar beeping)

(Richard) When police officers carried out a welfare check

on a Bournemouth flat, they discovered

the dismembered body of taxi driver William Spiller

stored in plastic containers.

The postmortem showed that wounds across William's body

were inflicted by a Stanley knife, also found at the flat.

William's son, Nathan, was the only other person living at the flat.

Around the time of the murder, neighbours

had reported a commotion.

Nathan was spotted on CCTV buying cleaning products

and then went on a spending spree with his father's money.

After a nationwide search, police arrested William's son, Nathan,

and charged him with murder.

(Brian) He eventually goes to court and he pleads not guilty.

As part of that not guilty plea, he is offering up a defence,

a defence that is known as diminished responsibility.

If you're found guilty with diminished responsibility,

you cannot be given a whole life sentence.

You will be sentenced to a much lesser term of imprisonment.

There's an element of sadism, almost,

in this, because he's making William's girlfriend

and the family of his father

go through the horrific details of the crime.

If he'd have pleaded guilty, none of that would have happened.

But now he's got the best of both worlds.

He's trying for that.

He's trying to get a reduced sentence,

and he's enjoying the details of his crime coming out.

And it's a kind of celebrity notoriety

that you get from that as well.

So I think that would have appealed to him because I

do think he wants attention.

(Brian) As part of Nathan's diminished responsibility plea,

Nathan accepts that he killed his father.

He accepts that he watched him die and that he didn't

call an ambulance that could have potentially saved his life.

He then says he has no memory whatsoever of those events.

Nathan then says the next thing he remembers

is he's in the shower washing off the blood from his father.

Now, I would suggest that the cognitive thought process

of realising that you have to wash the blood off to get rid

of evidence means that there is a thought process that has been

followed from the actual event of killing his father,

which he has accepted.

And it's selective.

He's been selective in what not to remember.

(Richard) The prosecution argued against the plea

of diminished responsibility, claiming

Nathan had a clear financial motive for murdering William.

Father of 48 supporting a son of 26 is nothing unusual

as long as that son is in higher education

and he's seen to be achieving.

The arguments come when he's dropped out.

Nathan owed his father 36,000 pounds.

What are you going to do? When are you going to get a job?

That's when the arguments come.

And of course, there would have been a disappointment

for the father if that didn't happen.

In my opinion, he had a sense of entitlement.

He wanted the money.

His father was fed up with giving him money.

He clearly had a grudge against his father.

And of course, the most telling thing

is the fact that the way Nathan wanted

to spend his time after he'd murdered his father

was to support his mother, show her a good time,

go out and spend money with his mother.

And he obviously had an emotional attachment to his mother

that was absent for his father because he took his mother's

surname, not his father's surname.

The Oedipus complex was first talked about by Sigmund Freud,

and he suggested that sometimes a son competes with the father

for the attention and love of the mother

and so that the son and father are in conflict.

And in some cases, this can be so extreme

as to lead to violence between the father and son

and even death and homicide.

(Richard) After the prosecution rested their case,

it was the turn of Nathan's defence team.

Nathan's barrister suggested during the case

that this was an unusual crime, that it

was a result of a sudden snapping that caused the killing

and that the crime had no motive.

(Richard) But did William's body support this claim?

The multiple injuries on William's body

would tend to indicate a sudden explosion of violence.

But the fact that Nathan watched him bleed to death

and then dismembered his body

would suggest something far more calculated.

We know that Nathan had used a Stanley knife to inflict

the injuries, but the police also found a couple of saws

that he'd used to dismember the body.

William Spiller was a big man.

He was 6'5" - that's nearly 2 metres tall -

weighing 160 kilogrammes.

That's about 25 stone.

Dismembering him would not have been easy.

Joints are particularly complex with interlocking

pieces of bone held together with tight ligaments.

Take the shoulder joint, for example.

Here, the head of the humerus, the clavicle,

and part of the shoulder blade all are fixed together

by tight fibrous bands.

And then we can see how they're surrounded

by muscle and other ligaments keeping it together.

Dismembering a body is never easy.

It must have taken him hours and hours.

William's dismembered body revealed that this was not a moment

of madness - quite the opposite.

This was a considered and determined action.

There's no doubt that the son was emotionally

detached from his father.

This particular individual would have been particularly callous

and not have much empathy for the victim.

And to have systematically tidied up and then stacked them in boxes

after dismembering the body shows a level of detachment from reality

and what has gone on in the room.

It's so bizarre that he went to all that trouble

to dissect the body, to put it in all these plastic boxes,

which, to me, seems like utter contempt -

utter contempt for his father.

And then to build them up and to put the TV on

and to use it as a stand,

I mean, that really is a horror movie.

When the police eventually arrived,

they found that his father's head

was actually in the filing cabinet.

No matter how emotionally detached you are from your father,

you know what your father looks like.

So the head represented a challenge

to the way he was trying to blank the whole thing out of his memory.

And so it had to be hidden away so the son could forget

what had happened in that room.

(Richard) But was his motive really just purely financial?

So from the ferocity of the attack,

from slitting his throat with a Stanley knife,

and then when his father was laying on the floor,

pleading for an ambulance and bleeding out,

to continually stab him

means there was real hatred in the act,

which suggests that it wasn't just an argument

about financial concerns

and about the amount of money that his dad, as a taxi driver,

was paying for his son to sit at home.

This was something else.

(Brian) During the court case, Nathan makes

an absolutely explosive claim.

He says that when he was 13, he was sexually abused by his father.

He'd forgotten about it.

And suddenly, it came back to him.

(Jane) Nathan tried to claim that he'd suffered from PTSD,

that he'd been abused by his father,

and that he'd had a really bad childhood.

If somebody has post-traumatic stress disorder

from a long period of abuse, if that had happened in childhood,

then yes, I could see

how a person could snap

or a child might want to get out of that situation.

It seemed to kind of come out of the blue,

his defence of abuse.

(Brian) He knows it can't be proved.

But also, it can't be disproved as well.

(Kevin) Nathan says, well, I was sexually

and physically abused as a child.

That may well have happened.

We do know that children who have been sexually abused

under the age of 10 are much more likely

to commit homicide than children who have not had that experience.

But with no evidence, the court finds it difficult

because he could be making it up as a way

of defending himself.

William is described as a caring, loving father.

(Jane) His father had always kept him.

He didn't have to have him at the flat.

Nathan didn't have to go and live there.

He could have gone and lived somewhere else, you know,

after his degree course finished.

It just doesn't wash.

There's nothing there actually in his past.

So they had nothing there that could back up that claim.

(Brian) Nathan is easily able to manipulate William,

to wrap him round his little finger

to get him to do what he wants.

We can speculate as to why William is happy to do that.

It could be guilt.

It could be a whole host of reasons.

It's up to the jury to decide whether or not they believe him.

(Richard) We'll never know exactly what happened

between William and Nathan and why their relationship broke down

with such devastating consequences.

After a three-week trial, the jury took just

two hours to return their verdict.

Nathan was found guilty and sentenced to life imprisonment.

The judge remarked during his sentencing

that this was a callous, cold-blooded, premeditated murder

of William, the motive being financial.

He believed the money was his.

He had the sense of entitlement.

It was there, and he would do what it took to get this money

and then to cover his tracks.

(Brian) I think the only way you can look at Nathan,

when you know all the circumstances

and all the facts of this case,

is, he was a cold, calculating person.

He was driven by money.

People say that money is the root of all evil.

And that's actually not correct.

What is correct is, the love of money is the root of all evil.

Nathan is just pure evil.

It was a fatal wound to the neck that killed William Spiller,

but the lack of defence wounds proved he

didn't expect to be attacked by his own son

and left to bleed to death.

Nathan tried to cover his tracks, throw the police off the scent,

and claim childhood abuse had triggered the assault.

But the clinical dismembering of William's body

proved this was no sudden snap of anger.

It was considered and calculated.

And for that reason, his body revealed the cold, hard truth

about his murder, and a dangerous killer was brought to justice.

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