All language subtitles for The Truth About My Murder S01E05 1080p WEB DL H264 BTN_track3_[eng]

(gun shot)

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,

including on some of the most
high-profile cases of recent times.

I've learnt that the dead don't hide
the truth and they never lie.

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

From a state-of-the-art laboratory
with ground-breaking technology

that uses digitally scanned
sampled bodies,

I'll be investigating
a series of intriguing murders

where, from the victim's bodies,

I'll be revealing to you the truth
behind those horrific crimes.

(camera clicks)

(bell tolls)

Centerville, a small, quiet town
in rural Iowa,

the heart of the American Midwest.

Serious crime is almost unknown,

but in May 2018

a terrible house fire
shocked this community.

Inside firefighters discovered
the badly burnt body of a man.

It looked like a tragic accident,

but could it have been
something much more sinister?

And could the body tell the story
of what had happened?

(country music)

Centerville is a small,
close-knit community

of about 5,000 people.

Everybody knows everybody.

We know their families,
we know their history.

Everybody looks out
for one another.

It's how it's always been.

Many of the families have been there
for generations.

A community that has
a strong agricultural tie,

so most of the families are farmers

who have been farmers
for generations.

We have one middle school,

one high school
for all the students.

They all go to the same school,
participate in the same sports.

I was born and raised
in Centerville,

moved away for a few years.

When we started having a family
we decided to move back,

just because of the community
and how close it was.

'But at 7.30am
on Saturday May 5th 2018,

'Centerville's peaceful life
was turned upside down.

'Barbara Pasa was driving
to a soccer tournament

'where her children
were due to play,

'but before she got there,

'she received several shocking
phone calls from her neighbours.

'Her house was on fire.'

'Barbara rushed back, knowing
her husband Tim was in the house.'

(Moore) One of the neighbours
was driving, leaving his house,

saw fire coming
from the Pasa residence.

Two neighbours from across
the street went in the front door,

looked to the left
and saw charring and smoke.

'They acted fast and called
local firefighters on 911.

'They arrived within minutes.'
(sirens wail)

(firefighter) "OK, 0-1-1-11."

"Let the fire department know
that there is a lot of smoke

coming out of the east side
of the house."

When the fire department
first got there,

they saw black smoke rolling
from the east side of the residence,

which is where the master bedroom
is located.

They immediately started
to extinguish the fire.

(indistinct chatter over radio)

'All four of the town's fire trucks
arrived.'

(siren wails)

There was a lot of smoke.

One of the firefighters
that went in to battle the blaze

did suffer from smoke inhalation
and had to be taken to the hospital.

(officer) "Know if anybody's home?"

'Neighbours told police officers
on the scene

'they thought
there were people inside.

'They called in Assistant
Chief of Police Mike Moore.'

I knew the occupants
of the residence,

so I was just unsure
what we were going to find.

I was initially informed that
there may be three bodies inside.

I was fearful at that time that
it may be the children involved.

'When the firefighters
finally managed

'to get into the master bedroom,
they discovered a terrible sight.

'Barbara's husband, Timothy Pasa,
was found dead on the bed,

'and his body had been
severely damaged by the fire.'

The most obvious injuries

were the terrible burns present
on Tim Pasa's body.

Doctors use the "rules of nines"

to estimate the surface area
of the body that's been damaged.

I can demonstrate that
on this sample body

on the digital autopsy table.

The head counts for nine percent,

the arms are nine percent,
the upper chest is nine,

the abdomen is nine,
the legs are nine, front and back,

and the back of the body
is split into nines as well.

And using that estimation,

we could work out that 97 percent
of the surface of Tim Pasa's body

was damaged by fire.

It's most unusual to find

such a high percentage
of burns in a house fire,

and the burns on the body
are estimated by doctors

as first, second or third degree.

First-degree burns are like sunburn,
just reddening of the skin.

Second-degree burns have blistering,

if you touch something hot
in the oven.

Third-degree burns are when the skin
is damaged and burnt through,

exposing the muscle.

In Tim Pasa's case, most of the
burns were first- or second-degree,

relatively superficial,

but the extent of the burns
suggest that he wasn't moving,

that he was asleep
at the time the fire was burning.

It was a tragic end to a family man.

(Moore) Tim Pasa
was a well-liked guy.

Very well-known in the community,

whether it be through involvement

with his children's sports,
school activities...

He was a member of a band
for a long time.

Tim was born and raised here

and I believe he lived here
all his life.

I have a lot of memories of Tim.

Our children were the same age

so they did
a lot of activities together.

We'd sit together a lot of the times
at sporting events.

'The most important thing
in Tim's life was his family.'

Barb and Tim had been married
for several years,

I believe it was 18.

They had two children
that were both in high school.

She was also from the area
and spent her entire life here.

I'd known Barb Pasa
for probably 30 years,

was actually a friend
of the family's,

grew up
with one of my older sisters.

'They were a very normal family

'in a small town where things
like this hardly ever happen.

'They simply weren't prepared
for such a terrible tragedy,

'and neither was the rest
of the community.

'Most of its emergency services
are volunteers.'

Currently the Centerville Police
Department has 11 full-time officers

and we have three
reserved police officers.

Centerville Fire Department,
it's a small department.

There's three
full-time firefighters,

and the rest,
it's a volunteer department.

'Now they had a fatal fire
on their hands.

'They had to investigate
how the fire started.'

We conducted a walkthrough of the
residence shortly after the fire.

Started doing their investigation.

(indistinct radio chatter)

'As soon as Barbara arrived,

'she told the firefighters
that Tim was inside.

'She feared the fire had been caused
by a lit candle

'she had placed
in the master bedroom.'

Barb told me
that she had lit a candle

that morning before leaving,

because the dog had urinated
in the bedroom

and she was using the candle
to cover up the smell.

She advised that she'd set
the candle on the nightstand.

When fire investigators
found the candle,

it was on the floor
next to the bed, on its side.

On the floor
there was an unburned white spot

that was consistent
with the candle being on the floor

at the time of the fire,

which means that the candle was
sitting upright during the fire.

It did not fall from a nightstand
or anything like that.

'And that wasn't the only thing

'that Mike and his fire department
colleagues thought was odd.'

Tim's body was very badly damaged
in the fire.

It was what I would call
inconsistent

with the amount of fire damage

throughout the room
where the fire took place.

The condition of Tim's body
initially was suspicious,

but not enough to state
that anything may be criminal.

'Mike decided that it was an unusual
but still an accidental fire.

'All the emergency services
left the scene.

'There was just one thing left
to do, an autopsy on Tim's body.'

Any time there's
a death investigation,

an autopsy will be completed.

'The autopsy was performed
by the state medical examiner,

'pathologist Dr Dennis Klein.'

The cause of death
and the manner of death

may not be immediately obvious

and the autopsy is the best way
to get at these answers.

What was the injury,
disease or poisoning

that ultimately led
to that person's death?

Despite the burns,

most people die in fires
by breathing in noxious gases.

And the most important of those
is carbon monoxide,

which binds the haemoglobin
in the red blood cells

and stops them carrying oxygen.

So that the blood,
when it travels round,

can't carry the necessary oxygen
to the heart or to the brain

and these organs eventually die

and the individual
will then die too.

Carbon monoxide is present
all round us, in our bodies.

If you smoke, you've got about 10%
in your bloodstream anyway.

20% will give you headaches
and you'll feel unwell,

but 30%, you're likely to die.

But what else can we find in the
body when we look at it at autopsy?

When fires are burning,
smoke is inhaled into the lungs.

And we can see that here.

The lungs themselves
may be blackened,

but most importantly, throughout
the trachea and the bronchi

there's little particles
of black soot deposited

that shows someone was alive
at the time the fire was burning.

But when Doctor Klein
did all of these tests,

he had a big surprise.

Despite having burns
on the outside of the body,

there were not
the characteristic findings of soot

in the upper and lower airways,

which occur
when a person breathes in smoke.

And then when we did a test,

looking at what's called
the carboxyhaemoglobin saturation,

the amount of carbon monoxide
that accumulates in the blood,

it was not elevated.

So these two very key findings
were absent

and made me come to the conclusion

that Tim did not die
of smoke inhalation

and that he was likely dead
before the fire had occurred.

This is very surprising.

Generally a fatality at a fire scene
has died as the result of a fire.

I've examined hundreds
of fire deaths in my career,

and in my experience,

less than two in 100 were dead
before the fire started.

Finding a victim who is dead

before the fire starts
is always suspicious.

This autopsy had turned
the investigation on its head.

I realised that this was going to be
a difficult and complex case.

And we're conferring
with law enforcement officers

who attend the autopsy.

I realised
that I had more work to do,

but I realised
they had a lot more work.

In May 2018,

a small town in Iowa
was rocked by a fatal fire.

Tim Pasa, a well-known
and much-loved family man, had died.

It was a tragedy
for the whole community.

But at the autopsy, Tim's body
revealed a horrific surprise.

Tim was dead before the fire
started.

'The police needed extra help,

'so Iowa State Fire Marshal David
Linkletter came to investigate.

'David teaches fire investigators
to recognise the signs of arson,

'based on his own extensive
experience.'

I've been a fire investigator
since 2000.

And in that time I've been
on well over 800 fire scenes.

I perform fire scene investigations

and hopefully try to determine
how this fire originated,

how it spread
through that area of origin,

and ultimately caused
all the damage that it did.

'Two days after the fire took place,

'David and his team started
to investigate

'the fire in the Pasa home.'

So we went down Monday, where
they had prepared a search warrant

to re-enter the property,
to take a look at the fire scene

and give an assessment
of how this fire originated.

(siren wails)

'Something had troubled
the local firefighters

'as soon as they arrived.'

(indistinct chatter)

'They couldn't hear
any smoke detectors beeping.'

Neighbours, witnesses,

as well as the officers that
responded and the fire department,

at no time did they ever hear
any smoke alarms

going off in the residence.

Smoke detectors are pretty robust.

They can withstand a lot of damage
and still keep working.

(beeping)

We discovered a smoke detector in
the unburned portion of the house,

outside the kids' bedrooms,
where it had been disabled.

There was a door that flipped open
for the battery,

and that door was open
and the battery was exposed,

rendering
the smoke detector inoperable.

When we closed the battery door,

it worked
like it was supposed to do.

Once we'd worked our way
through the house,

we discovered a nine-volt battery
on the floor,

near the door to the bedroom.

Near that area was also
a melted smoke detector.

And directly above that
was the line of demarcation

where a smoke detector once was,

and it had melted
and fallen onto the floor.

And we very quickly were speculating

that that battery had been removed
from the smoke detector

and thrown onto the floor
before the fire event.

Obviously the battery just didn't
fall out of that smoke detector.

'Both smoke detectors in the house
had been tampered with.

'And that wasn't the only thing
that troubled the investigators.'

'They'd been wondering
about Barbara Pasa's behaviour.'

When she arrived on scene,
she asked if she could see Tim.

I advised Barb
that Tim was in the ambulance

but that he was in very bad shape
due to the fire.

I allowed her at that point
to go into the ambulance

and have a moment with Tim.

It wasn't
until a couple of minutes later,

when I re-entered the ambulance,

and she advised me that she did not
want an autopsy completed.

Yeah, and that to us
was a pretty serious red flag,

and so it really provoked
a lot of questions.

Why does she not want
to have an autopsy performed

on her late husband?

'Barbara later said that the only
reason she was opposed to an autopsy

'was she didn't want Tim's body
any more cut up.'

Law states that the medical examiner
has authority of that body,

and so even if a family member
is opposed to that autopsy,

if a medical examiner
feels that it's necessary,

an autopsy will be done.

Both the state police detective
and a local police detective

actually wanted to attend
the autopsy.

That's not a usual situation
for a house fire.

So we knew
that there was some concern.

Dr Klein was sure that Tim hadn't
died as a result of the fire,

but could he have died
as a result of natural causes

before the fire started?

If I was investigating this,
I'd want to see the medical records,

and we know from those records
that he had mild hypertension

and that his heart
was slightly enlarged.

Firstly he'd have looked
at the heart muscle to see

whether there was any evidence
of thickening of the muscle.

The heart has two main pumping
chambers, the left ventricle,

which pumps blood round
the whole of the body,

which is the main,
powerful pumping chamber, here.

He noticed that the heart muscle
was slightly thickened

but not significantly so.

So while the heart
was slightly enlarged,

it wasn't significantly so.

The second feature Dr Klein looked
at were the coronary arteries.

These are the blood vessels

that supply oxygen
to the muscle of the heart.

He'd have looked at those to see

if there was any evidence
of furring up,

a blockage of those arteries,
and there wasn't any.

So Dr Klein was able to conclude
that there was no evidence

of significant natural disease
with the heart

that could have killed Tim Pasa
before the fire started.

So Tim must have died
from unnatural causes.

Dr Klein would have looked
carefully at the chest.

He found no evidence of any
bruising, any fractured ribs,

any bullet wounds or any stab
wounds.

Is there any evidence of any injury
to the face, the skull, the brain,

that might indicate blunt trauma?

Then he perhaps had a look
at the neck

to see whether there was any
evidence of strangulation,

evidence that can still be found

after a body has been burnt
in the fire.

But none of these things
were present.

And so one thing remains.

Could Tim have been poisoned
or drugged?

We ordered an expanded panel,

which is a broad panel
of various drugs and poisons.

Much to my disappointment,
the first toxicology result

showed what we call therapeutic
concentrations of medicines

that we knew he was on
for his blood pressure.

That would not explain his death.

So we were still left
with an uneasy feeling

that we had
suspicious circumstances,

we didn't have a good explanation
for his death,

so that meant we still had
our work cut out for us.

'Without clear answers
from the autopsy,

'the pressure
was back on the detectives.

'And their concerns about Barbara's
behaviour had been growing.'

Barb did not show any emotion.

"If you need anything,
let me know, OK?"

Whether it was when
I was initially speaking with her,

or after seeing Tim's body,

there was no emotion shown
whatsoever.

Other people, throughout the day,

expressed that her behaviour
was just odd

for someone
that had just lost her husband.

'On the day of the fire,

'Mike noticed Barbara had posted
a message about Tim on Facebook.'

I was Facebook friends with her.
I saw the post.

I believe it said
something to the effect of,

"Tim was a good father..."
etc, etc, etc.

It was just a very strange post
for someone to make

that had just tragically lost
their husband.

'In fact, Barbara seemed very keen
to get on with her life

'as quickly as possible.'

Barb, either the day
of the incident or the day after,

contacted a local real estate agent,

advising that she would like
to look at houses to move into.

'The biggest surprise came
on the night of the fire

'when Barbara's 16-year-old son
contacted the police.'

He'd reached out
that he wanted to speak with me

about what had taken place
that day at the residence.

He expressed that he had concerns
that his mom, Barb,

may have been responsible
for Tim's death.

'It was a shocking claim
from a teenager,

'especially against his own mother.

'But he claimed
his parents' relationship

'had been getting steadily worse
in the previous months.'

He advised that they had not been
getting along for quite a while,

that they had recently talked
about getting a divorce.

He also advised
that his dad had confided in him

that he believed Barb had tried
to poison him with Benadryl

a couple of weeks prior
to the incident.

He began writing notes,
thoughts that came to his head...

...and provided those notes to me.

'As the police spoke
to more members of the family,

'it became clear that life in the
Pasa household was much more tense

'than it appeared from the outside.'

Barbara and Tim,
at the time, lived together,

but through interviews we found out

that it was
more of a divided household.

They were more roommates
than husband and wife,

and just weren't getting along
well at all.

'While Mike interviewed
friends and family,

'Special Agent David Linkletter

conducted a detailed
fire investigation.'

When we arrive at a fire scene,

we're gonna usually take a look
from the area of least damage

to greatest damage.

We're gonna walk through the house

and just see what was going on
during this fire.

'David soon confirmed what the local
firefighters had suspected.'

'The only place where the fire

'could have started
was the master bedroom.

'According to Barbara, it was caused

'by the candle she had lit
on the morning of the fire.'

We evaluated the entire room

and we quickly discovered
that, you know,

there was more going on than
just a candle starting this fire.

The hallmark of fire investigations
is really analysing burn patterns.

The burn patterns are gonna tell you
where the fire occurred

and where it didn't,

and in this case we all were very
concerned about the top of the bed.

There was a very distinct pattern
on the headboard and the wall

that indicated there was definitely
a fire in that specific area

burning for a much longer period
of time

than anywhere else in this room...

...as witnessed by
the extreme damage to the headboard

and the clean burn
to the wall against it.

Usually the area that burns
the longest

is gonna be the area
where the fire originated.

'But could the candle have played
any part in the fire,

'as Barbara claimed?'

The problem with that

was that that candle did not burn
vigorously enough

to catch anything else
in that room on fire.

It just sort of burnt
that little area of carpeting

and really did not travel
anywhere else.

'In this position, a lit candle
could have caused a lot of damage,

'but David could see
that it hadn't.'

All of the wood underneath that bed,
next to where that candle was,

did not catch on fire.

There's less damage
as you go toward the candle.

Burn patterns did not support
the theory

that this candle started this fire.

It didn't happen.

'While no fire investigation
is simple,

'investigators felt
they'd found enough evidence

'to be sure
where the fire had really started.'

We were confident
the fire originated on the mattress.

The damage went from the top,
in other words the mattress,

down and up and out.

This was obvious
that the bed was lit on fire.

'That left a big question
about Barbara's actions.'

'The investigators
were beginning to wonder

'whether Barbara was trying
to mislead them.'

Why would she point out this candle

in this room
with all this damage in it?

How could she point that candle out
right away?

We really felt, with all
of the damage on the mattress,

and the little bit of damage
that that candle did cause,

that that candle was deliberately
placed onto the floor

and that fire damage
was deliberately caused

in order to direct us, direct
investigators in a different way.

In Iowa, police were investigating
a case of arson and murder.

Tim Pasa was found dead
at the scene,

but his body had revealed

that he had been killed
before the fire even started.

Perhaps it held further secrets.

Prime suspect was his wife, Barbara.
But what was her motive?

'The investigators knew that Tim and
Barbara's marriage was in trouble,

'but they also discovered
they had money problems.'

They were living
paycheque to paycheque,

and Barb advised that she had
an online spending problem.

They were looking at a divorce.

Barb was one who kind of liked
a status in town

and didn't have the money,
if they weren't married,

to live the lifestyle
she was living.

'And the family's financial records
revealed a recent change

'that struck the investigators
as particularly significant.'

We discovered that,
through Barb's employer,

that they had increased
Tim's life insurance up to $200,000

in the last several months
prior to his death.

'That suggested Barbara
had a financial motive

'to kill her husband.

'But the investigators
still didn't know how Tim had died.'

(Klein) Without another
definitive cause of death,

there was going to be
a lot more work to be done

in order to try to identify

what drugs and poisonings
we needed to test for.

I did what a lot
of forensic pathologists do,

and that is I pick up the phone
and I call experts

who can help me
take the case further on.

What other possibilities
should we be looking at?

How do we expand our toxicology
testing in order to try to find

what actually happened to Tim
and caused his death?

And we're also going to need the
help of law enforcement detectives

to also help us in what
potential drugs we need to test for.

At the time of the incident,

Barb was a nurse
at her local hospital.

She worked in the operating room
and assisted with operations.

Which is very important information,
because that then opens up medicines

that would not normally be tested
for on toxicology screens.

So a second toxicology screen
was performed

for more exotic
or unorthodox substances.

And it was that when we received
the result back of propofol.

Propofol is a very powerful
anaesthetic drug

that's very commonly used
during surgery in hospital.

It's a drug that very rapidly
induces unconsciousness.

But it also lowers the blood
pressure and suppresses breathing,

so it needs to be administered
by a skilled anaesthetist.

Propofol is such a potentially
dangerous drug

that it's even been used
in assisted dying cases in Canada

and has been suggested as a drug

that could be used for executions
in the United States.

But it's a drug
that should only be found

in cases from a hospital setting,

so the finding of this drug
in Tim's body

was a great surprise
for the investigators.

(Klein) 'In my career, I've never
seen this drug in a case.'

And we knew that Tim had not had
any type of medical procedure

in which he received propofol.

'So how had such an unusual drug
got into Tim's body?'

The most likely answer
to that question

is that someone else
injected the propofol into his body.

'Dr Klein now felt sure

'that Tim's death was not natural
or accidental.'

And that finally left homicide,

in which a person dies
at the hands of another,

and that fit very well

with the circumstances
in my findings at autopsy.

'Dr Klein quickly told the
detectives about his findings.'

It was bittersweet.

It was, "Now we know
what caused the death,

but now we know more about
the case and what has to happen."

In all the years I've investigated
fires, this was the first

where we've proved the person was
murdered prior to the fire.

It really confirmed to us

that this fire was more than likely
started to conceal a crime.

'The investigators were now hunting
for a murderer,

'and Barbara Pasa
was their prime suspect.'

'They needed to find out

'if she could have stolen
a lethal dose of propofol

'from the hospital
where she worked.'

After using propofol,

a doctor or surgeon
may not use the entire amount.

It is capable
of just being thrown in a trash can.

There's no logging
that needs to be done.

Barbara had very easy access
to propofol.

It was her job to clean up
those items used in a surgical room,

and she was also in charge
of taking the trash

from the surgical room
to the dumpster.

'Tim had been concerned
for some time

'that his wife was trying
to poison him.'

Tim had contacted
one of his sisters,

a week or two prior, I believe,

told his sister, "Oh, by the way,
I think Barb tried to poison me."

He didn't explain any further.

I believe that was the last
text message that was sent.

'This seemed to corroborate

'what Tim's son had revealed
about his father's fears,

'that Barbara was trying to poison
him with Benadryl,

'an over-the-counter medicine

'used to treat allergies such
as hayfever.'

I think if you were trying
to poison someone with Benadryl

you'd need a lot of Benadryl,
and they would notice the symptoms.

So you'd be tired,
you'd become very dry.

It's an antihistamine.

Maybe Tim was noticing that
over time.

'And the investigators found
something else

'that might link Barbara
to the fire.'

The master bathroom,

we found a grill lighter sitting
on the countertop next to the sink.

Which we found a little odd,

for a grill lighter
to be placed in that area.

She told police investigators
she used that grill lighter

to light the candle that morning
before she left.

'This grill lighter was a bit
over-the-top to light a candle,

'but it would have been

'the perfect device to set light
to the mattress.'

'The police now felt they had enough
evidence to interview Barbara.'

(Moore) We were asking her
several tough questions.

She knew that we knew
something was suspicious

and criminal in nature.

The following day
an ambulance call was made

from her mother's residence.

It was determined that
she was suffering from an overdose

and she was immediately taken
to hospital in Des Moines.

(siren blares)

I spoke with Barb and her mother

and determined that Barb
had taken an overdose of insulin.

Barb was a diabetic.

She knew how to regulate
her insulin.

I would say
it was an intentional overdose.

'When Barbara was discharged
from hospital,

'Mike was there waiting for her.'

(siren wails)

I think she was surprised to see us

outside the hospital
when she was released,

but state law says that
the medical staff had to advise us

when she was being released.

We immediately then placed her
under arrest for arson and murder.

'When Tim Pasa died in a house fire
in May 2018,

'his badly burnt body was still able
to reveal the truth

'about what had happened to him.'

He'd been killed by a powerful
anaesthetic drug called propofol

and then his house
was deliberately set on fire.

The prime suspect for both crimes?

His wife, Barbara Pasa.

'Barbara Pasa was charged
with first-degree murder

'and first-degree arson,
nearly two weeks after the fire.

'It was a big shock
for this small town.'

Since I've been with the department,
since 2002,

this was the first murder
that we've had in Centreville, Iowa.

'From the autopsy evidence,

'fire analysis, witness testimony
and phone records,

'investigators pieced together
what really happened

'on the day Tim Pasa was murdered.'

'Saturday May 5th 2018.

'By 6.30am, the couple's
two children had left home

'to catch the school bus
for their soccer tournament.

'Barbara told police she followed
them in her car at 7.00am,

'but she had lied.'

It was determined
that Barb actually left later

than she originally told us.

'7.08am, Barbara sent a text
to her daughter

'saying she would be late.

'7.20am, a neighbour saw Barbara's
car still parked in the garage.

'During this time Barbara must
have disabled the smoke detectors.'

The first smoke detector
was easy to tell.

With that door being opened,

we really believed that that
detector was disabled intentionally.

The one located in the area
of the fire was off the wall.

The battery was about three feet
away from the smoke detector.

We were confident that that detector
also had been disabled,

the battery had been taken out
prior to the fire.

'This was also when Barbara must
have injected Tim with propofol.'

It was the state's theory that
she did poison him with the propofol

and then set the bed on fire

in hopes of covering up
any evidence.

We really believe that the candle

was deliberately placed
on the floor, burning,

to set the carpeting on fire,

but a separate fire
was placed on the mattress

near her husband's deceased body.

That fire grew
in much more intensity

and caused the damage that we had.

So the state's stance

was Barb used the candle
as a distracter, a decoy,

to say that's how the fire started.

'Having killed Tim

'and, she believed,
covered her tracks,

'only then did Barbara leave home.'

(Moore) Barb left the residence,
went to a bank ATM,

which also had a camera on it.

We were able to secure evidence
to show the timeframe for that,

which was around 7.26am.

'Several neighbours saw smoke coming
from the master bedroom window

'of the Pasa home.

'They called 911.'

(sirens)

'Firefighters arrived
just three minutes later.

'Neighbours desperately called
Barbara but got no reply.'

(phone rings)

(Moore) She had received several
missed phone calls, text messages.

She had reported that she was not
able to receive those calls.

'But by tracking
the cell phone towers

'her mobile connected to as she
drove, investigators could show

'that Barbara deliberately missed
at least five phone calls

from neighbours trying to warn her
about the fire.'

(Moore) She finally, around 7.50,
around 8.00,

responded to missed phone calls
and text messages.

The thing that was very interesting
to me

was that she spoke with the kids,
she spoke with other family members,

but knowing
that Tim was at the residence,

she never once tried
to call Tim's phone.

'The investigators suggested

'that showed Barbara knew
Tim was already dead.

'The investigators were satisfied
Barbara had murdered Tim...

'...and the trial began
on September 17th 2019.

'The autopsy evidence was critical.'

Having done a complete autopsy,
reviewing his medical records,

and learning about the circumstances
surrounding his death,

the most compelling and medically
defensible cause of death

would be from propofol,

because there was really no other
good explanation for his death.

I felt very comfortable
that this was a homicide.

'The defence argued

'that the level of propofol
found in Tim's blood was low,

'much less than you'd find

'in a patient being anaesthetised
for surgery.

'But there is a good explanation
for this.'

Propofol is very rapidly absorbed
from the bloodstream

into the fattier parts of the body.

And there's quite a lot of fat
in the human body naturally.

A lot of it's underneath the skin
of the legs and the arms,

but there's also a large amount
of fat inside the abdomen,

and a big sheet of fat that covers
the bowel called the omentum,

and the drug will have moved from

the bloodstream
into this fatty tissue.

But its damage
will already have been done.

Its effect on the brain,
its effect on breathing,

starving the brain of oxygen
and causing death

will have taken place.

Because of the redistribution
of the drug throughout the body,

it's not a surprise that only
a low concentration was found

in the blood sample
taken at the autopsy.

But that low concentration
doesn't mean

that he wasn't injected
with a fatal dose of the drug.

It had done its damage
and then disappeared.

'In court,
Barbara tried other arguments.

'She even suggested

'Tim might have been using propofol
as a recreational drug,

'but it was easy to dismiss
this theory.'

If he was someone
who would abuse it,

the amount of propofol
in his system,

there would have been a needle
still in his arm.

He would have passed away
that quickly.

There were no needles found
in the location of the fire.

And it would be pretty hard
to inject yourself

and then start a fire,

which appeared at this point
to be intentionally set.

'But the defence tried to discredit
the fire analysis as well.'

The defence really challenged me
on the candle theory.

They really wanted that candle
to be what caused this fire.

The defence was possibly
blaming the dog

for tipping over the candle,
which caused the fire.

When we take the totality
of the situation,

it's hard to argue that that candle
fell off the nightstand

and caused that fire.

That candle was deliberately placed
onto the floor

and that fire damage was
deliberately caused

in order to direct investigators
in a different way

so that she could conceal
killing her husband.

'After a week of evidence,

'the prosecution argued
they had proved Barbara's guilt.

'Her motive was financial gain.

'Her means was the propofol
she stole from her workplace.

'And her opportunity occurred
that Saturday morning,

'while the children were
on a school bus

'and she was alone at home
with Tim.

'The jury deliberated
for three hours.'

The jury came back with a verdict

of guilty on both arson first degree
and murder first degree.

In the state of Iowa,

murder first degree
is mandatory life imprisonment.

On the arson
it is a 25-year sentence.

Barb will spend the rest
of her natural life in prison.

'For a small Midwestern town,

'discovering
that a well-known local nurse

'had abused her position of trust
to murder her husband

'was very shocking.'

When Barb was finally convicted,
it was relief.

It was relief
for the whole community.

I hope it's something I don't have
to go through again in my career,

but I'm glad we were able
to use all our resources

and get answers for the family
and for Tim.

But also knowing that things
were still going to be hard.

Here we have two children that had
now lost both their parents,

one to death and one to prison,

so that was... it was bittersweet
on that aspect of it.

'The community rallied round
as best it could.

'A fundraising campaign

'to help the children replace
what they had lost in the fire

'smashed its original goal,

'raising $20,000 for them
in less than a week.'

The children make me proud.

They've moved on.
They have terrific adult lives.

Erm...

They're my kids.
They're part of my family as well.

This was nearly the perfect crime,
but bodies never lie.

And Tim's body had revealed

that he had been injected
with a fatal dose of propofol.

If Tim had lived
just a few more minutes,

his body would have eliminated
all of the propofol

that Barbara had injected into him

and the evidence of his murder
would have disappeared.

Even more shockingly,
propofol is not a painkiller.

Tim could have suffered
terrible pain as he burnt to death,

and Barbara, as a nurse,
must have known that.

And that is what makes this
such a terrible crime.

Subtitles by accessibility@itv.com