All language subtitles for murder.uk.s03e05.1080p.web.h264-cbfm_track3_[eng]

(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."

(suspenseful music)

In Berkshire, in the home counties,
half-sisters Kylie Dembrey

and Tara Randall
grow up inseparable.

(Tara Randall)
She was very caring,

wanted to do everything
for everyone.

She was very, like,
cheeky, and she was gobby.

But there was nothing
that we weren't used to.

Just sassy.
(laughs)

(David Wilson) Kylie's mum met
and married Tara's dad in 2000.

It was a bustling family home
with five siblings.

The sisters could be a handful.

Kylie, in particular,
was known for her energy.

She was funny, loving.

She could be naughty.

She used to wear my clothes.

(laughs)

She definitely didn't like school.

She used to go to the clubs,
friends' parties and stuff.

But she wasn't bad.

(David)
Tara naturally grows protective

of her younger sister,
who suffers from epilepsy.

But as they enter their teenage
years, Tara begins to mature.

And her interests shift to boys,
and to one boy in particular -

Mark Sinclair.

(Tara) When I first met Mark,
I was about 17.

Literally, I met him,
and within, like,

I think it was, like, about
three months, we were dating.

And he was just very kind, caring,
just a nice, genuine bloke.

(David) Tara's relationship
with Mark Sinclair

develops rapidly.

And as it does, she begins to see
a disturbing change in him.

I fell pregnant
with my first child at 17.

Then the drugs started, the drink.

He became nasty,
like, real spiteful.

Wanted to cause an argument
all the time.

(David) As Sinclair and Tara
settle further

into teenage parenthood,
his behaviour worsens.

When I had my eldest,
the beginning was fine.

Then, when he was about three...

three months old,
the drinking got worse.

I had to call the police because
he'd left my house with my son.

If I refused to give him money
for drugs or drink,

it would just cause a big uproar.

When I refused
to give him money one night,

he literally threw me out
of my bed with my son in my arms.

You could just see
the rage in his eyes.

(David) Sinclair, who had been
in care himself

from the age of 11,
clearly struggles with parenthood.

Dr Donna Youngs has
researched his mental health,

including the diagnosis
of a serious personality disorder.

Dissocial personality
disorder is...

it's almost like
a low-level psychopathy.

It's one that was formed
very early in life.

I mean, we're talking
before the age of seven,

before the age of eight years old.

He rejects, he renounces
all the normal social ways

of going about doing things.

He has a recklessness.

There's a callousness,
a callous streak to him,

alongside, curiously,
alongside a very passionate,

intense, loving streak.

(David) Former detective
Paul Barton believes

Sinclair's diagnoses, when combined
with his recreational drug use,

created a potent recipe
for disaster.

(Paul Barton) Sinclair had been
known to the police

since he was 17 years of age.

There are a number of people
in this country

that have personality disorders.

Not all of them
are managed by the police.

But I think this is particularly
tricky when somebody

with a personality disorder is
also addicted to substance abuse,

such as drugs or alcohol,
because the effects that has

on those individuals
is they become more volatile.

They become more paranoid,
but also,

probably the medication that
they're supposed to be taking

for their personality disorder is
actually not working

because of the other substances
they're taking.

He had quite an extensive
criminal history,

which include a range
of serious sexual assaults,

violence, threatening behaviour,
and also weapon offences.

So he was quite
a dangerous person.

(David) Mark Sinclair's psychology
is, well, quite simply, alarming.

When you combine a diagnosis of
anti-social personality disorder,

which would have a lack of
empathy, a recklessness to it,

with chronic substance abuse,
you've got somebody

who really does not know
any social boundaries whatsoever.

And the drugs aren't
creating that psychology.

What they're doing
is stripping away

any last vestige he might have
about social convention,

about rules, about boundaries.

And therefore, Tara's living
with a very dangerous man indeed.

Initially bewitched
and seduced by Sinclair's charm,

Tara doesn't know the man
she's actually with.

She's unaware of his
mental health diagnoses.

And she certainly doesn't know
of his extensive contact

with the police
prior to their relationship.

This included being charged
at the age of 17

with sexual assault
against a minor.

He was a completely
different person,

completely different person.

He was... he was nasty.

Everything had to be his way.

And he was just evil,
absolutely evil.

(David)
Bearing witness to Sinclair's

increasing abuse of Tara,
younger half-sister Kylie

often steps in to offer support.

(Tara) Kylie used to come
and baby-sit the children for me

when we used to go out.

Obviously, some of it
she was there for.

So she did see quite a lot.

(David) In 2008, having had
two children with Tara,

Sinclair's drug use
and his lifestyle choices

lead to a prison sentence.

And it's at this critical time
that Social Services intervene.

They had done all
their assessments.

And they... they basically said,
because of the domestic violence

part of it, they would take my
children for their own protection.

So basically,
it was him or my children.

I chose my children.

I didn't want to be with him.

At that point in my life, I had
got to the point where I'm like,

I actually don't want
to be with you no more.

(David) Social Services
knew their priority

was the children's
permanent safety.

They had to assess
the long-term risk Mark posed,

given his conviction
for a violent offence.

Even with Mark behind bars,
Tara was given a stark,

non-negotiable choice -

sever all ties to him now,
or the children would be removed.

Tara is finally free from Sinclair

and his increasingly dangerous
level of abuse.

But on his release from prison,
a shocking secret is revealed.

Mark and Kylie
had been seeing each other.

Mark and Kylie met when Kylie
was baby-sitting

for Mark and Tara,
Kylie's older sister,

which tells us Mark doesn't

subscribe to the normal
social rules of behaviour.

(David) Sinclair dating Kylie,
Tara's sister,

is simply another form of control.

It's the ultimate form
of betrayal for Tara herself.

It further isolates her.

It further can degrade
her own sense of self-worth.

And, of course, this goes back to
Sinclair's underlying psychology.

This is somebody
who can't empathise

with another person's feelings.

And so he must realise the impact
on Tara when he starts dating Kylie

is to make her
feel even more abandoned,

worthless, degraded.

(tense music)

(suspenseful music)

(David) What exactly does
Kylie Dembrey see in Mark Sinclair?

I think it's that
bad-boy-type image

because that's how he comes
across, is a bad boy-type person.

The fact that Kylie,
when she met Mark,

would have been very naive,
very impressionable -

she was so young, 16 -

is a real factor in the way
their relationship formed.

This relationship beginning
in this clandestine way,

her being chosen
above her sister in some ways.

And I think that all this
excitement, all this drama,

and the charisma that
I have no doubt Mark has

would have literally
swept her off her feet.

(David)
At the news of their relationship,

older sister Tara
is immediately concerned.

I said to Kylie that, obviously,
I didn't want the contact

because I didn't want him knowing
anything about my children.

(David) But other family members
are not worried.

Mum Theresa doesn't know about
Sinclair's dark criminal past.

Kylie had been
seeing him for a few months

before we actually met him.

He seemed kind.

He treated Kylie like a princess.

Obviously, he made her happy.

(David) In 2008, Kylie and Sinclair
move in together.

I think the choice
that she has made

has been
a particularly unfortunate one

because he can be so deceptive.

Because this covering of
attractive, charming,

charismatic qualities
is just... is just that.

It is a facade beneath which
this very different personality

also lingers.

They seemed like a really
good couple together.

(David) But over the course
of their early relationship,

Mum Theresa does begin to notice
things, things of serious concern.

Used to come home, and she
would have a bruise

or a mark on her body.

Obviously, when I used to ask her,

she would say things like
she'd fallen over.

But she wouldn't
tell us the truth.

I said to her, why do you want to
be with someone who's controlling,

telling you, you can't wear this

and you can't wear that?

(David) Perhaps it's because,
like Sinclair,

Kylie herself had been diagnosed
with a personality disorder.

Hers, however, makes her prone
to unstable relationships

and a deep worry that
people might abandon her.

How does she know
just how abnormal it is

for her to be in fear
of violence from her partner?

How would she know?

She doesn't have
that background experience.

What we have with Mark
are two very distinct components

to his personality.

So we've got
this intensely loving,

passionate, doting,
romantic side of him,

and then this
ever-present violent potential

waiting to be unleashed.

(David) Later in 2008,
Kylie receives news

that intensifies her connection
to Sinclair.

She's pregnant by him.

(Theresa) When Kylie first
found out that she was pregnant,

she was like any mother.

She was excited.

She couldn't wait.

(David) The pregnancy, however,
doesn't give any pause

to the abuse,
though Kylie will often downplay,

rationalise, and contextualise it.

It's quite common in sort of
longstanding domestic abuse

situations when
the police get called,

and the perpetrator is arrested
and then taken back into custody.

And then the victim has
that kind of cooling off period,

that downtime to start thinking
about the consequences.

And it's not uncommon
for a victim of domestic abuse

to actually change their mind
and say,

you know, I don't want
to press charges.

(David) In September 2008,
the authorities

do recognise Kylie as a victim.

Sinclair hurts her badly.

He's arrested and pleads guilty
to battery.

This is the police's
first official record

of contact with the couple,
and they talk to Kylie.

(Paul) I don't think Kylie
ever saw herself as a victim.

And I'm fairly confident
Mark wouldn't have allowed her

to see herself as a victim.

(David)
On release from custody,

Kylie allows him
back into her life.

(Theresa Randall)
He came out of prison

a month before baby was born.

(David) Their child's birth
offers a moment of relief.

They seem to have put it all
behind them.

We were all happy.

Mark was excited, cried.

And it was just a happy day.

(Paul)
So you've got to remember that

Kylie was only around
about 16 years of age

when she first met Mark.

So then to suddenly be in love
and loved by an individual,

you know, and have a child
with them has probably

had a massive impact on Kylie.

You know, she doesn't
know any different.

And I think
she really relies on Mark,

who's probably said,
if I go to prison,

who's going to look after
the kids?

Who's going to put
food on the table?

We're talking about
an emotional dependence,

where he had... he had a drug
addiction, but she certainly had

an emotional dependence on him.

(David) By 2009, calls to
the police about abuse at the house

Sinclair shares with Kylie
come in thick and fast.

Her mum, Theresa, begins to see
the physical evidence for herself.

(Theresa)
He had no respect.

He used to smash my house,
punch the doors.

It was scary.

You didn't know
what to say to him.

He would go for you.

Because he's done it
to me a few times.

(David) One of the questions
that I think most people ask

in situations like this is,
why does the person being abused

not get up and leave their abuser?

It's not as simple as that
for a number of different

but interacting reasons.

The first is,
after she has been abused,

there would then be
an intense period

in which Sinclair
would show her love.

And that relationship between
what's healthy and what's abusive

becomes blurred.

And we know from decades
of research about domestic violence

and coercive control that,
ironically, the person being abused

is at greatest risk
when she articulates the fact

that she is going to leave.

Now the risk is not just to Kylie
but also to their young son.

And reports of domestic abuse
and Mark's previous convictions

bring the couple urgently to
the attention of Social Services.

(Paul) We know that
the child was taken away

into care by Children's Services.

And that's an extremely
serious step to take,

taking a child away
from its mother.

But I can only assume that the
Social Services and other partners

had considered the risk
that Mark posed towards Kylie

and felt that was
the only opportunity

they had to safeguard that child.

We've got to remember,
the police have been called

on a number of occasions
to this address,

where Kylie had refused
to support a prosecution.

And therefore, you know,
if she was making excuses

for Mark's behaviour,
how could she

possibly safeguard her children?

It made me feel very angry, upset.

I couldn't believe it.

I'd lost my grandchild.

(David) As her one-year-old son
is taken

into the protection
of Children's Services,

Kylie, too, is devastated.

Despite the heartbreaking loss
of her child,

Kylie still can't
give up on Sinclair.

After the baby was taken away,

Mark and Kylie
still stayed together.

(David) Even after Kylie
loses access to her child,

when the child is taken into care,

that, ironically,
must bring her closer to Sinclair

because she feels
even more worthless,

she feels even more abandoned,
and therefore,

will cling on to Sinclair
in a way that

she hadn't previously clung on to

because it becomes
more intensified.

She's bereaved, I would suggest.

She's feeling lonely,
abandoned, and worthless.

(tense music)

And Sinclair's behaviour is
becoming increasingly volatile.

He's arrested for violent
offences and burglary

and spends time in and out of
prison and mental health hospitals.

He always comes back to Kylie.

While Mark can be
this callous, violent individual,

I have no doubt
of his love for Kylie

and the way that they simply

couldn't stay away
from each other,

and rings absolutely true to me.

There's a kind of till...

till-death-do-us-part quality
to their initial relationship.

I mean, I think we even have
Mark saying at some point,

if you try to leave me,
I'll kill you,

just totally bringing together
the two parts of his personality,

the passionate and the violent.

In that one sentence,
you get Mark.

(David) By 2010,
still living in Newbury,

their relationship
is marred by periods

where, if Sinclair isn't in prison
or hospital, he simply goes AWOL.

Kylie used to try and ring him.

Sometimes he would
change his phone number.

The only time Kylie
would ever hear from Mark

is if he would ring her.

But then Mark would just come back
as like nothing had happened.

(tense music)

In the course of their
12-year relationship,

they were on and off, and Mark
had another child elsewhere.

(David) He has an affair
and gets someone else pregnant.

She took it really badly.

And, obviously, he promised her
that he would never

have another child
with anyone else.

(David) After everything
they've been through,

Kylie is devastated.

But then she becomes pregnant
by him again.

(Theresa)
When Kylie told me that

she was pregnant
with her second child,

I was excited for her.

But I was always scared
that this baby

could go the same way
as the first baby.

(David)
Anxious over the possibility

of losing her second baby,
Kylie decides to keep

the child away from Sinclair.

She seeks safety
and enters a women's refuge.

(Theresa) She went
to a mother and baby house.

And whatever Kylie did
with the baby,

they used to write it down

so that Social Services knew

that she was being a good mum.

(David) Over the course
of around ten months,

Kylie develops a sense of
independence with her child.

However, in July 2012,
Sinclair tracks down

the refuge where Kylie is staying.

He assaults her and is
sentenced to 22 weeks in prison.

There's now little chance
they'll reconcile.

Kylie had said so many times
that she would leave him.

But it never happened.

(David)
Half-sister Tara is certain

Kylie has left Sinclair for good.

She even hears her
make a solemn promise

to their father on his deathbed.

I had a phone call
from my other sister, Rebecca,

to say that my dad
was down at the hospital,

really poorly with pneumonia.

Dads absolutely hated Mark.

The only reason why he was civil
was because he was with Kylie.

Kylie promised our dad that...

that she would never
get back with Mark.

And that's when she promised
that she'd leave him.

(David)
But then the family feels certain

Kylie has found strength
through her second son,

away from Sinclair for good.

But then...

Kylie used to secretly
meet Mark where she lived.

And Social Services found out.

And because she'd done that,
that's why they took the baby.

(David)
Kylie's child is taken into care.

Ironically, what that does
is make her even more dependent

on Sinclair.

And so that puts even greater
control in the hands of Sinclair,

because without Sinclair,
Kylie has nothing.

(tense music)

(suspenseful music)

(David) When authorities
in Berkshire discover

Kylie has been meeting
Sinclair in secret,

they have no option but to offer
protection to her second child.

It just breaks my heart.

I felt angry.

I was annoyed because I knew...

That she would always choose Mark.

(Tara) I messaged her,
and I said, look,

you made Dad a promise.
And she said, I know I did.

But I can't...

I've... that's when she said
about the bond,

and he's the only part
of her children.

In fact, he probably
made himself feel

like the victim of all of this.

You know, he lost his
two children with Tara.

He's now lost his
two children with Kylie.

Kylie's had her children
taken from her.

You know, is she a bad mother?

Is this punishment for her... for
her past behaviours, if you like?

(tense music)

So in 2012, Mark and Kylie
actually moved out of the area.

Now, one might think, well,

that's an opportunity
to start all over again.

But when I read something like
that, I'm immediately thinking,

this is quite risky
because they're moving

from one police area to a
completely different police area,

another local authority area.

So all these partners aren't
going to be aware of the history

of Mark and Kylie.

And so had they gone somewhere
else to actually almost start

that cycle of violence again,

where they're undetected
until such time,

you know, the police are notified?

(David)
By 2017, there's clear evidence

that Sinclair's cycle of violence
is becoming even more brazen.

There was this
particularly nasty incident

where he chased his mother
and a police officer

with a meat cleaver.

And it's no surprise that when
it came to a review of his risk,

he was deemed high risk.

And for me,
that shows that his pattern

and offending behaviour is just
getting worse and worse and worse.

But obviously, this then makes it
a really high-risk situation

for Kylie,
who's in that relationship,

and on a number of occasions
has been

the sole victim of his violence.

(David)
With Sinclair in a secure unit,

Kylie relocates multiple times,
first to an Oxford refuge,

then back to Newbury.

Yet the cycle repeats immediately
upon his release, and they reunite.

They go to live
with her mother, Theresa,

who quickly notices Sinclair's
increasingly strange behaviour.

(suspenseful music)

(Theresa) When Mark
used to live at my house,

he used to come into my bedroom
at night

and just look at me
and watch me sleeping,

which I thought was a bit strange.

(David) Sinclair's mental health
issues worsen,

and they are exacerbated
by his drug use.

He's now diagnosed with further
conditions, including sociopathy.

And then he sells
something precious of Kylie's

to a local pub landlord
so as to get money to buy drugs.

There will have been umpteen
examples of his callousness

in their relationship.

We know, for example,
that he sold Kylie's puppy

in order to get money for drugs.

That absolutely sums up
the dissocial personality disorder

characteristics that Mark had.

(David) Sinclair strives
to convince Kylie

his crimes are her fault.

But Kylie remains trapped,

unable to leave Mark
without proper support.

In June 2018,
authorities in Berkshire

grow so concerned
for her safety that they step in

and initiate a MARAC.

(Paul) A MARAC is a Multi-Agency
Risk Assessment Conference,

and it's chaired
by an independent person.

And a number of partners
are invited to that meeting,

which would include the police.

It may involve probation,
housing, local authority, health.

And the idea is that
those partners share information

that they have
on that particular family.

They identify
what those risks are.

It may be that probation
can review licence conditions

of an individual.

It might be the police can do
some more monitoring around there

or flag the address that, if there
are any domestic incidents,

police will respond to urgently.

And so to say, the whole idea
is to get this holistic approach

on this family
to try and problem-solve

and actually try
and stop the violence

happening in the first place.

(David) Authorities contact
Kylie's local medical practise

and ask them to encourage her

to engage
with domestic abuse services.

Kylie doesn't attend.

But around this time,
she decides

she and Mark
should live separately.

(Paul)
Living separately from him,

she's still
in a relationship with him.

And some people might think
that's a little bit strange.

What she's probably doing is,
she's removing herself

from the risk
of day-to-day violence

and that controlling behaviour.

But she's keeping him happy,
to a certain extent,

in that she is still
in a relationship.

She was saying that she just...
she'd had enough

and didn't want to be with him
no more.

(David) We know that the most
dangerous time for the victim

of domestic abuse is when she,
or indeed, he, decides

that they're going to do something
about the abuse

they're experiencing by creating
space within the relationship,

or indeed leaving.

That's the time at which
the threat from the abuser

becomes most acute
because the abuser

sees this as a loss of control.

And he will try
to reassert his control

to prevent that space
in the relationship or to, indeed,

to prevent the victim
from leaving the home itself.

And what he might do in that
situation is use more violence,

and indeed, on some occasions,
use lethal violence.

(tense music)

Theresa is invited
to Kylie's new flat

in the village of Theale
in West Berkshire to have dinner.

Mark is also there.

I went round there that evening.

We had dinner.

We were laughing
and joking around.

It was like a normal day.

(David) Theresa sees no sign
that Kylie plans

to end the relationship
permanently.

Even if she is, Kylie has
good reason to hide it.

Mark said to her,
if you leave me, I'll kill you.

I think he... he was almost,
in saying this,

I think he was almost
trying to warn her

that that is... that is who he is.

(David) Tied to a man who'd
rather she died than leave him,

Sinclair hurts Kylie again.

(Paul) We don't know
exactly what went on

and what led up to this.

But there was clearly
a violent altercation

which resulted in Mark
strangling Kylie

to the point of unconsciousness.

(James Aldridge) It was
an act of extreme violence.

After Mark rendered Kylie
unconscious through strangulation,

he stabbed her in the neck first
and then the heart.

So clearly, the violent acts,
he knew what he was doing.

Even though maybe a red mist
had descended on him,

he knew what he needed to do to...

to render the result
that happened.

(Paul) There are two different
types of injuries, if you like.

There are the stab wounds, which
are violent and very personalised,

and then you've got
the strangulation as well.

And this, for me,
demonstrates a real anger

and hatred
towards that individual.

(David)
People get the impression

from watching film or TV drama
that strangulation is quite quick.

It can happen literally in seconds.

But if you're going to kill someone
through manual strangulation,

it will take three,
perhaps even four minutes.

The person can lose consciousness
more quickly,

but they won't actually be dead.

And all the time that
the perpetrator is strangling,

he is literally looking
into the face of his victim,

watching life drain away.

That gives them the ultimate form
of power and control.

All of the warnings,
all of the interventions,

all of Kylie's fears
had proven to be true.

(tense music)

(David) After strangling, stabbing,
and ultimately killing Kylie,

Sinclair does something
out of character.

Mark had brutally killed Kylie,
and then coldly called the police

to say exactly what he'd done.

It's as if the murder
is a momentary aberration

to his general personality.

It's indicative of the way that
his personality would have seemed

to oscillate between
this warm individual

and this person who could be
so callous and violent.

(David)
Whether Sinclair is calling 999

through genuine guilt
or to mitigate his actions,

police quickly arrest him.

They then break the
devastating news to her family.

The police came to my house
at quarter to 5:00

in the morning and said

that I need to sit down,

that something has happened
to my daughter, Kylie.

Of course, I didn't believe it.

I just sat like I was
in another world.

I started to cry.

I couldn't believe
what I was hearing.

I had a friend call to ask me
if I'd heard about my sister.

And obviously, you'd been,

well, what do you mean?
type thing.

And they was like,
oh, she's been killed.

And I'm like,
don't be... don't be stupid.

Do you know what I mean?
What... don't mess about.

And then obviously,
I rung my other sister,

and she confirmed that...
that, actually, yeah,

she'd been murdered.

Obviously, she'd been
stabbed in the neck

and straight through her heart.

I just couldn't believe
that he'd go that far

or that he'd even do that.

(David)
Family liaison officers

arrange for Tara and Theresa
to see her for one last time.

The first time
after what happened,

I saw my daughter...

In a coffin.

I couldn't believe...

That that was my daughter
lying there.

We went in, and she was
just laid on in the coffin.

And obviously, she's as...
she's as tiny as Theresa is.

But her face was just blown up,

where I'm assuming it's where
he strangled her.

It was just... it just
wasn't nice to look.

She was absolutely beautiful,
don't get me wrong.

But it just wasn't nice
to see what he had done.

(solemn music)

(David)
Throughout her entire adult life,

Kylie remained loyal to Sinclair.

But could anyone
have acted to help her?

He wasn't being managed
around his risk.

If he were, then there's
certain actions

that police and probation
could take.

So it could be regular visiting
and monitoring of his behaviour.

It could be for him to undertake

certain courses to address
his behaviour.

But when somebody's not being
managed in that process,

it's simply just recognising
this particular individual

may pose a risk.

And therefore, if a call comes in
and his name is linked

to that particular call
or the address is linked

to that particular call,
then the police

should treat that call as urgent
and respond immediately

and do as much as they can to...
to address that risk.

I have no doubt that there were
people in the... in the services,

within the police that...
that saw the warning signs here

only too clearly.

But what can they do?

There has to be some degree
of voluntary awareness

on the part of... of the partner.

There has to be
some admission of a problem.

There just wasn't that readiness
yet in Kylie to see exactly

how much of a risk she was at.

Whether she would have started to
comprehend that,

we'll never know.

(David)
Following Kylie's death,

the Thames Valley Police
state that they aim

to establish if there are any areas
or lessons to be learned.

By 2019, authorities intensify
their efforts

to build the case against Sinclair
as they prepare for trial.

He tells the police
he didn't mean to kill Kylie,

claiming that there were
mitigating circumstances.

He tried to state that
his actions were down

to his personality disorder

and that he shouldn't be
convicted of murder,

but he should be convicted
of manslaughter.

And this presents, you know,
a challenge

for the prosecution team.

(tense music)

(James) It can be haunting
seeing someone who's capable

of that violence and them being
not very far away

from where you are sitting.

Courts are safe places
where there are guards.

But you do get a sense of the
seriousness of what's happened.

It can be quite harrowing
and haunting

to see a person in the dock...
a person in the dock

who's capable of such violence.

(David) The trial exposes
Sinclair's explosive nature.

(James)
He threw a tantrum.

He stormed out at one point,
and he started shouting loudly.

We couldn't see him at that point,
but we could hear screams.

(David) Throughout the trial,
Sinclair continues to claim

he didn't mean to kill Kylie.

(James) The defence said
that it wasn't a premeditated act.

However, it was an act where
Mark Sinclair knew the targets

that he needed to kill Kylie
in terms of

first strangling her, and then
stabbing her through the heart

and in the neck.

They'd look at the previous
convictions of Mark as well.

And obviously, doctors would
be involved to assess him

around his personality disorder.

But we know lots of people
have personality disorders

in this country, but they
don't go around strangling

and stabbing people.

(David) Of course, Sinclair
is going to try and weaponize

the fact that he's diagnosed
as having

an anti-social personality
disorder.

He wants to try and create
a narrative which sees him

as being less culpable
for killing Kylie,

and therefore mitigate the charge
down from murder to manslaughter.

But this is really just
another form of manipulation.

On the 12th of March 2019,
after three hours of deliberation,

the jury returns a verdict.

Mark was convicted
of the murder of Kylie,

and he was sentenced
to life imprisonment

with a minimum term of 21 years.

As soon as they
said that the verdict

had come back murder
and not manslaughter,

the relief was just unreal.

Because it just felt like,
to me, yes, he got life,

but minimum 21 years,
that's still not enough to me.

Nothing will ever be enough.

Do you know what I mean?

But to hear that he...

the verdict of murder, it was
just like a massive relief.

And it was just like,
we got what we wanted.

(David) At sentencing,
Sinclair makes one final request.

(Theresa) Mark said to the judge...

(pensive music)

Please, can I say something?

And the judge said,
yes, you can, Mark,

as long as you're not abusive.

Mark said to me, he said,
Theresa, can you hear me?

I just totally blanked him.

And he said he was sorry
for what he'd done...

And he never planned it.

(David)
The judge was clear -

Sinclair was entirely
responsible for his actions.

(James)
The judge in the case

said Kylie wasn't
able to remove herself

from a very dangerous person
and a very dangerous situation,

and said for the family to not
beat themselves up

over what had happened because
he... he sort of said that it was,

in a way, unavoidable.

And they shouldn't take shame
in what happened because

there... there was something
binding them.

But sadly, that did prove fatal.

(David) Sinclair was the one
responsible for this ultimate act

of violence and for all the years
of pain that Kylie suffered.

But today, her family focus
is on honouring her memory

with love and affection.

(Theresa)
I miss the fun we had...

The laughs we had...

Even the arguments we had.

But we still had a love,
mother and daughter.

(solemn music)

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