All language subtitles for Fatal.Fraud.S01E06.1080p.WEB.h264-CODSWALLOP_track3_[eng]

(Narrator) Every fraud
begins with a promise,

but most don't end in a murder.

(Person)
I'm out here on a motorcycle,

and I found what looks
like a human skull.

(Narrator) A quick fortune,
easy money, or a life torn apart.

The killing of the McStay family
was not an accident.

(Narrator)
But behind these illusions

lie calculated deceptions...

Why would your phone show you
at the gravesite?

(Narrator)
Carefully hidden in plain sight.

I have no clue.

How could something like this
happen in a place like this?

(Narrator) Sometimes these
criminals are backed into a corner

and feel their only way out
is to kill.

He went to that house that night,

and the worst of the worst
got the best of him.

He turned to violence.

(dramatic music)

(soft music)

My name is Britt Imes.

I'm a chief deputy
district attorney

for the County of San Bernardino.

Fallbrook is a fairly rural,

small town
in northern San Diego County.

It sits in the rolling hills

east of the Pacific Ocean.

Given that somewhat rural nature

and small-town feel,

crime just didn't seem to be
an issue.

(Narrator)
For 40-year-old Joseph McStay

and his wife, Summer,

Fallbrook was the perfect place
to raise their young family.

The McStay family was

your typical young upstart family.

Summer and Joseph
had originally lived

over on the coast,

but when the kids
started coming up,

they bought a house

in which they could raise a family
in Fallbrook...

Can we watch the movie?
Yay!

(Summer McStay)
Curious George.

Curious George!

With room enough for them to grow
and for him to run his business,

and they chose a very sleepy
neighbourhood of Fallbrook

that was, you know,
100 houses or so

nestled amongst avocado groves

in the hills
to the west of the busy freeway.

(dramatic music)

I'm Scott Kraft,

and I'm editor at large

at the "Los Angeles Times."

Certainly, that neighbourhood
is quiet, middle class.

It feels fairly private...

kind of a nice suburban community.

(Britt Imes) Joseph McStay
was a self-made businessman,

small entrepreneur.

He focused initially
in a drop-and-ship company

for desktop water features,

like little fountains
you would put on your desk.

And he slowly grew that business

into custom-made features
for businesses,

like a waterfall
in a lobby of a doctor's office

or a restaurant or a mall.

In that, he grew to have a larger
internet presence

utilising a Webmaster.

(Summer laughing)

Summer was a free spirit.

Oh, G!
Come on, G!

(Joseph)
Whoo!

She was a life force,
an energy in Joseph's life.

When Gianni came along
and then Joe Jr.,

she really focused
on being a stay-at-home mum,

taking care of the boys

and really focusing
on their family life.

(Narrator)
The McStays' story was a happy one

of a successful family
living the dream...

Until early February 2010...

(phone ringing)
When that dream was shattered.

Starting on February 9th of 2010,

certain things occur
that lead to the reporting of,

the McStay family is missing.

Joseph's mother, Susan,
enquires about the fact

that she's not been able
to get a hold of Joseph.

Almost simultaneously,
the other business partner,

Dan Kavanaugh, who is in Hawaii,

has been trying
to reach Joseph repeatedly.

Mike McStay, Joseph's brother,
gets involved.

Initially, his response was,
well, give it a few days.

Maybe they went surfing.
Maybe they went to the mountains.

Summer had a house
up in the mountain area.

Maybe they just needed to get away
for a few days.

At some point,
Mike McStay ends up going

into the house...

and realises,
something's not right here.

And that's when the
sheriff's department is notified.

Patrol deputy comes out
and does kind of a welfare check,

and he takes
the initial half dozen photographs

of the condition
of the house at the time.

(camera shutter clicking)

They find the window
to Joseph's office slightly ajar.

There was no dead bodies.

There was no blood
all over the place.

And it just kind of looked
like the house had been empty

for several days.

(Scott Kraft)
The way the house was left,

it seemed like they were
not intending to be gone long.

It also seemed that they had left

in a bit of a hurry.

There's uneaten food...

a bowl of popcorn,
some scrambled eggs.

There's actually
an apple on the stairs

with a couple bites out of it.

Leaving things behind like that...

stuff on the counter
that could spoil...

just seemed so unusual.

It felt like they must have left
with a sense of urgency.

When it came to the condition
of the bedrooms

or the closets and clothing,

it was quite dishevelled, and it
looked a little out of place.

It was very difficult to tell

if there had been
any kind of struggle

or any kind of violence
in that house,

because the house
had just been purchased

by Summer and Joseph
a few months before.

There were
open paint cans all over.

The family seemed to be living
out of suitcases.

Upon a first look,

an investigator will go,
OK, they got up and left.

Maybe they were in a hurry
for an appointment

and didn't finish their breakfast
and didn't have time to clean up.

Mike goes, OK,
let's give it a couple days.

Let's see what happens.

Let's see if they just went
on a quick getaway.

(dramatic music)

So come the 15th,

Mike calls
the sheriff's department

and officially reports
them missing.

(Narrator) As the police
began their investigation

into the missing family,

the case made national headlines.

There was an outpouring
of concern.

I mean, these were
two young children...

and then their parents.

No one had heard from them.

There was grave concern
over where they had gone,

what had happened to them

(Scott)
No one really knew what happened.

It seemed to be from the stories
that had been written that...

I mean, it's just so unusual
for a family of four

to disappear into thin air.

My name is Dr Keri Nixon,

and I'm a consultant
forensic psychologist.

When somebody's missing,
there's always a question mark

and there's always
an element of hope.

We know from many missing cases

the psychological impact
on families is horrific.

When it's unknown,
it's utter daily hell

to experience that.

(Narrator) Police began by looking
at their last known movements.

The initial investigation
by San Diego developed a timeline

of Joseph's kind of comings
and goings around the time...

or right before the time they were
reported missing by the family.

(Narrator) It was discovered
that on the day he disappeared,

Joseph McStay met one
of his contractors for lunch...

a man known
as Charles "Chase" Merritt.

Chase Merritt was the person
who did the construction.

(Britt)
Charles Merritt was a fabricator

of these water features.

He would do the plumbing,
the glass work.

It was learned

that Charles Merritt
was kind of the last person

maybe to have been in contact
with him,

beyond the immediate family
of Summer and the boys.

And that developed into what
was believed to be a meeting

between Charles Merritt
and Joseph McStay

on February 4th, roughly midday.

(Narrator)
On February 17, 2010,

13 days after the McStays
were last seen alive,

police interviewed Charles Merritt.

(Detective) Let's start
with your name, Charles?

(Charles Merritt)
Charles Ray Merritt.

During that interview,
Merritt puts forth

a picture of the relationship...

the personal and business
relationship with Joseph

as one of,
everything is all right.

It's sunshine and rainbows.

(Detective) I mean, obviously,
have a business relationship.

Were you also friends, or was it...

(Charles)
Joseph was one of my best friends.

I can't remember a day
that I haven't talked to him.

Everybody loves Joseph, everybody.

He has no financial problems.

I mean,
over the last couple of months,

things have started picking up,

and everything
was looking really promising.

(Narrator)
During the interview,

Merritt described
his warm relationship with Joseph

and the successful state
of the business.

So one of the documents
that Merritt provides

during the interview
to San Diego sheriffs

is an email
between him and Joseph,

and it was from February 1st.

(Charles)
He had emailed me this on the 1st,

and we were going over
these numbers.

But these are the last emails,

the last few emails
that I got from Joseph.

(Detective) And your overpaid
amount, this Chase paid 173...

(Charles) $173,000
is what he's paid me.

$158,000 is what he owed me,

so I owed him $15,000.

In that email, Joseph lays out

the fact that Merritt
has not only been overpaid

about $15,000

but, in fact, owes Joseph $42,000

based on several
bad construction projects

that occurred that were attributed
to Merritt's fault.

So, in the end, while he's telling
investigators on the one hand,

you know, business is great,
our relationship's great,

he's showing them an email that...

on February 1st that says,
you owe me $42,000.

The investigators
did a forensic exam

of a couple different computers
that Joseph McStay had,

and towards the end of 2009,

the spreadsheet indicated
at one point

that Merritt was indebted
to Joseph to the tune of...

It varied from $64,000

up to approximately $200,000.

(Narrator)
During the interview,

police also discovered
Charles Merritt had access

to Joseph McStay's
financial records

through an accounting software
known as QuickBooks.

(Charles) Joseph and I sat down
and talked about the QuickBooks,

because Summer didn't know how
much money Joseph actually made.

She never did.

One of Summer's biggest problems
is credit cards.

She spends a lot of money.

It had become a big thing
with Joseph not letting her know

exactly how much money
he's making.

Merritt contended in his interview

that Joseph was delegating
that authority to him

in an attempt to hide
the business transactions

from Summer.

But that was the reason
that Merritt gave.

So he at least conceded
that he had the access.

It didn't make sense
for a small businessman

to actually turn over control
to finances

to a contractor.

That just did not make sense.

So a lot of anecdotal examples

of the financial mismanagement,
possible embezzlement,

or fraudulent activity by Merritt,
but nothing overly concrete.

(Fiona Moore)
My name is Fiona Hotston Moore,

and I'm a forensic accountant
and expert witness.

When we're looking
at perhaps an employee fraud,

we would look at the history
of the company's records

and what sort of monies
had been spent by the company.

And then we will look
for any unusual transactions,

things that we might not have
expected to have seen,

and we will look
at those unusual transactions

and see if actually
they are legitimate transactions.

(Scott) Detective DuGal told me
that he had looked

at the bank accounts
of the business.

He felt that the transactions
that had taken place

after Joseph and Summer
and their family went missing

seemed to be in line with things

that kind of business partners
would do.

The accounts weren't cleaned out
or anything like that,

that the transactions that he saw

in their QuickBooks
and in their accounting

seemed at that time
to be kind of normal.

They didn't raise
too many suspicions with him.

(Narrator) There was, however,
one aspect of Merritt's interview

that the police found intriguing.

One of the investigators noticed,

when Merritt
was answering questions,

he repeatedly said...

or referred to Joseph and Summer
and the boys

in the past tense.

And it was significant enough
that the investigator

even questioned him about it.

(Detective) Do you have
any knowledge or information

which indicates to you
that they're dead?

(Charles) No.
(Detective) OK.

And the reason that I ask
is because you have used

the past tense about Joe
a couple times.

Any explanation
as to why you may have done that?

(Charles)
Not really, I just, you know...

No.

(Detective)
Do you understand why I'm asking?

(Charles) No, of course.
I completely understand.

He had no explanation for that.

He just claimed he didn't realise
he was saying it.

(Narrator) Police decided to take
a closer look

at Merritt and his finances.

(Britt) Merritt is a hardworking
blue-collar craftsman.

His confidence exceeded
his ability to run a business,

be financially stable.

He regularly ran bank accounts

into negative balances
or zero balances,

incurred huge amounts
of overdraft fees,

all while apparently funding
his love

of being
a professional poker player.

Merritt did come
to the investigation

with a criminal history.

He has a criminal history
dating back to the late '70s.

Chase was not a reputable guy.

He had a history of small crimes.

He had served time for petty theft
and things like that.

And it was
Detective DuGal's understanding

that Joseph knew who Chase was.

He knew about his background
when he hired him.

(Narrator)
During the initial investigation,

police discover
one of the McStay family vehicles

abandoned close
to the Mexican border.

There's a parking lot
in kind of a strip mall

within walking distance
of the border.

A lot of people park there
and walk in across the border,

maybe go, you know, into Tijuana
and shop a bit and then come out.

And what had happened was,
this vehicle had arrived

between 5:00 and 9:00 p.m.,

and then after 9:00,
I think about 11:00 p.m.,

they had ordered it to be towed.

Detective DuGal went
and looked at the car, studied it.

Everything seemed normal.

There was, like, a coffee cup.
There was a bottle of water.

There were two child seats
in the back.

And he said it appeared to him
that if the four of them went,

there really wasn't room
for another person.

If someone had abducted them
in some way,

there didn't seem to be room
back there for a fifth person

in that vehicle.

(Narrator) With no hard evidence
suggesting foul play,

police kept an open mind
as to the family's whereabouts.

At some point...

investigators uncover, with the
help of the federal government,

evidence that fed into a story

that it was possible
the McStays had left

for a Mexican vacation.

It was somewhat amplified
by the fact

that during a search
of Summer's laptop,

she had in her browser history

a search
for vacationing in Mexico.

Joseph's father, Patrick,
had done his own research,

and he had somehow gotten

into Summer's email account...

and he had found
that she had purchased

a Spanish-language course...

another factor suggesting that
they had wanted to visit Mexico.

(Narrator) With the case drawing
national media attention,

police had to investigate hundreds
of potential leads and sightings.

One 3-inch binder alone of...

Tips...

where they were last seen,
who had last seen them,

and just the public's...

theory of the case
or what had happened.

But they had to run
all of them down

and dispel every single one
of them or prove them true.

(Scott)
One I remember was a waiter

in a restaurant in Mexico

had said that this family
had come in...

they left a map on the table
after eating,

a map of the area...

swore that that was the family,

because, you know,
had seen pictures and stuff.

Investigators went down there.

They checked fingerprints
on the map.

None of the family's fingerprints
were on it.

(Narrator) After checking
surveillance cameras

on the US border,

police discovered
further potential evidence

that the family
may have crossed into Mexico.

(Britt)
Customs and Border Protection,

after scanning hours
and hours and hours of video

within a time frame
that they went missing,

discovered a video

of what appeared to be
a family of four,

roughly the same stature,

roughly the same age
for the children,

crossing into Mexico...

wearing clothes that one could say
would be consistent with...

Summer especially.

Unfortunately, it was at night.

It's not the clearest video.

You don't see their faces.

And while investigators were
willing to explore the possibility

that it was them
and had gone to Mexico,

there was no other evidence
that they had.

The family was not convinced
it was them.

They believed strongly
that there was no way Summer,

the protective mama bear
of that family,

would take her kids into Mexico
at such a young age.

If it was, in fact,
a surfing vacation,

it was the wrong time of year
and no surfboards.

And why wouldn't they just drive?

(Scott) I think the theory that
they might have gone to Mexico

was interesting
to ordinary people,

but to the family,
it seemed not very plausible.

I mean, they did know

that Summer had searched
for travel documents to Mexico,

but I think the family thought
that they wouldn't do that.

And one of the reasons

was that Joseph had a son

from an earlier relationship

and he was very close to that boy.

And his family said,
there is no way

he would disappear voluntarily

and lose touch completely
with his son.

A missing persons investigation
is a lot more difficult

than a homicide investigation.

With a homicide investigation,
you know a crime occurred.

So you have certain legal tools
available to you

to get certain pieces of evidence.

You have the ability
to actually get a search warrant.

You have the ability
to actually detain people

and interrogate them,

differently than you would
if they were just witnesses

and trying to get background
information on a disappearance.

So San Diego
faced an uphill battle

even getting bank records
or phone records

or even a search warrant
to search the house,

which they ultimately did.

But that becomes a huge factor.

The second factor is,
you're talking about 2010.

The technology that exists today
did not necessarily exist then.

The tools that law enforcement
have now didn't exist then.

Nowadays, that data
is much more in-depth and complex,

including geolocation data
and more.

And it just seemed highly unlikely

that four people could disappear
like that and never be found.

I thought it was likely
there would be an answer,

but I also realised in doing
stories like this

that, you know, it could be
10 years, could be 20 years.

(dramatic music)

Three years, nine months,
and seven days after the McStays

were last seen alive,

a motorcyclist was enjoying
his three-day weekend...

Veterans Day...

riding his dirt bike
through the Mojave Desert,

which he's done dozens,
if not hundreds, of times.

As he was driving,
he noticed what appeared to be

initially
like a desert tortoise shell.

So he stopped.

And he flipped it over
with his boot

and realised it was actually
the top of a human skull.

So he calls 911.

(Person)
I'm out here on a motorcycle,

and I found what looks
like a human skull.

A deputy responds, and it clearly
is the top of a human skull.

And so they preserve the scene.

A full forensic team,
homicide investigators

descend on the area
and begin a two-day excavation

of what ends up being
two shallow graves

located in the desert.

(Narrator) It was established
that in the graves

were the remains of Joseph, Summer,
and their two children.

(Scott) I just learned about it
through a news alert

that these remains had been found.

And, very quickly,
I think they were identified,

and maybe the announcement
came at the same time

that they were the McStay family.

And I've got to say
that probably most people

who had covered that story
did not expect that.

That's not where

or how we expected them

to be found.

(Britt) There was a quick belief
that it was the McStays

because that was
the most obvious conclusion.

You had a family of four...
two adults and two kids missing...

and all of a sudden,
they're found.

It's consistent with it.

It ultimately was determined
through DNA testing

that the male remains were Joseph

and the female remains
were Summer.

It was deduced from that
that the other child remains

must be Gianni and Joseph.

Unfortunately, of Joe Jr., there
was insufficient remains left

to do any type of testing.

(Scott) When you think
about the logistics of that crime,

you would think multiple people
would be involved.

Like, how could that
have happened?

How could they be lured
into a situation

where they would all be killed?

How could they all be killed
in this way...

together?

(Narrator) Now with multiple
homicides to solve,

police began reviewing the evidence

from the initial investigation
three years earlier.

It became apparent

from Joseph's computer
and phone activity

that he was searching out
other fabricators,

other supply companies

to not only expand his business,

but what really became obvious

is to eventually get rid
of Merritt.

The investigation leads
to a series of interviews

and pieces of evidence
that shows that Merritt

not only was
a bad financial manager

but clearly was taking advantage

of the relationship
with Joseph McStay.

There was some untoward activity

when it came to money,

cheques being delivered,
cheques not being delivered,

supplies going missing,

or even Merritt
not doing the work.

Joseph was becoming aware of it.

(Fiona)
Normally when we're investigating

a business or employee fraud,

we talk about the fraud triangle.

That is, the opportunity
to commit that fraud...

is there the opportunity?

Is there the motivation?

And quite often the motivation
to commit fraud

would be something
like perhaps gambling debts,

perhaps financial pressures
that they're under,

perhaps some change
in their personal circumstances.

And then we talk
about the rationalisation.

So, typically, when people
are undertaking business fraud,

they may try and rationalise that
in their minds.

They may think that actually
it's part of their package.

Perhaps they think
they're actually due the money.

(Britt) Merritt portrayed
several times in interviews

that he was...

the reason behind the success
of this part of the business,

that it was his artistry
and his craftsmanship

that made Joseph successful.

And if you couple
that ego perspective

with, wait a minute,
now I'm not getting paid as much,

wait a minute, now I'm getting
paid extremely little,

and, oh, he's shopping
around using other people,

I'm about to be out of a job,

that could create desperation
in a lot of people.

(Keri Nixon) He was getting
less work from the McStays.

And this created resentment

and anger in him.

And he wanted to take

that anger out.

It wouldn't be understandable,

but it would be
a little bit more understandable

if he only took out that anger
and resentment

on the man
that he has the issue with.

(Narrator) After identifying
a possible motive to murder,

police took a closer look
at the activity

on the accounting software
around February 4, 2010...

the day the McStays disappeared.

When they dug into and did
a forensic audit of QuickBooks,

that's where they found
the concrete evidence

of fraudulent activity
being conducted.

They actually had cheques.

They could actually go
to the banks

and see which cheques were cashed,
which cheques were forged,

which cheques
were mysteriously deleted

from their accounting system.

That's where we moved
from anecdotal...

Merritt was stealing from Joseph...

to actual provable evidence

that Merritt was stealing
from Joseph.

We don't have cheques anymore.
I haven't written a cheque.

I haven't seen a cheque written
by a client for many, many years.

On the one hand,
I think written cheques

made a fraudster's life
slightly easier.

I think things have now changed,

and fraudsters try to do
things with electronic means.

On February 8th,
several cheques were written,

edited to change the date
back to the 4th,

and then printed

and then attempted to be deleted
from the audit trail.

The user didn't realise
that even though you delete it,

it actually still maintains
a digital footprint

and is still logged as activity.

One of those, in fact,
was, like, a $6,500 cheque

for a project that didn't appear
to have been finalised.

So all of that, while it leaves
some questions unanswered,

like a lot of things in this case,

it overwhelmingly established

that it was Merritt

who had access
and forged cheques to himself

and then deposited them
in his own accounts...

And then attempted to...

destroy evidence of such.

Money typically now moves
electronically.

It is easier to hide money
in a digital era.

However, forensic technology

also means
that it is very difficult

to hide money forever,

but people try.

(Narrator)
Police also discovered

a call was made
to QuickBooks customer services

on February 9, 2010.

Someone asked
the customer-service rep

to basically delete
the QuickBooks account

and all record of it,

and this caught the
customer-service rep off guard,

because in all of his experience,

no-one had ever wanted
an entire account deleted.

So he made very detailed notes

about that call.

And the process, though, was,

OK, Mr McStay, I will send you
a confirmatory email

with a hyperlink in it
for you to then log in

and confirm that that's the action
you want to take.

Until that's done,
we can't delete the account.

And that ended the call.

It also logged the phone number
from which that call was made.

That call came
from Charles Merritt's cell phone.

(Narrator)
Police began focusing

on Charles Merritt's
cell phone activity

around the time
of the family's murder.

On October 22, 2014,

Merritt was brought back in
for questioning.

Where did you go February 6th?
I don't remember.

Where do your phone records
show you're at on February 6th?

I have no clue.

High desert.
OK.

Where is a key area in the
high desert that we've discussed?

Where Joseph was buried, you mean?

Why would your phone show you...

at the gravesite on February 6th?

Not possible.
I wasn't there.

Why would your phone records
show you there?

Couldn't have.
Oh, they do.

(Narrator)
On November 5, 2014,

police arrested Charles Merritt

for the murder
of the McStay family.

(Britt)
The killing of the McStay family

was not an accident.

In California, to be guilty
of first-degree murder,

it has to be done wilfully,
deliberately, and premeditatedly.

It is not uncommon
for any defendant,

especially in a murder case,
to not admit guilt.

So it was not surprising
that Merritt did not.

He's presumed innocent.

He has to be proven guilty
beyond a reasonable doubt.

(Narrator)
While Charles "Chase" Merritt

was not separately charged
with financial crimes,

such as fraud, forgery,
or embezzlement,

his fraudulent financial activity

was central
to the prosecution's murder case.

You link these activities
to Merritt

multiple different ways.

One, he had made an admission

to having access
to the QuickBooks.

Second, who would create
a vendor account

and write cheques
to Charles Merritt?

Wouldn't they write cheques
to themselves?

And then the QuickBooks call
to delete the account

came from Merritt's cell phone.

Could it have been some
co-conspirator of Merritt?

Sure, but it was still
Merritt's phone.

(Narrator)
In January 2019,

after four years
of preliminary hearings,

Charles Merritt's murder trial
began in San Bernardino County.

(Scott)
Defence tried to make the case

that Dan Kavanaugh,
the other partner

who was the Webmaster effectively
of the business,

had more of an incentive...

to get rid of Joseph.

(Narrator)
The defence team maintained

that as an employee of the McStays,

Merritt had no reason
to murder the family.

(Scott) The things that remain
a bit of a mystery

are why any
of his business partners

would find it advantageous
to themselves

to kill an entire family.

(Keri) There was a high level
of violence,

violence that we usually see

when there's a very...

personal reason.

When we see
that level of violence,

there's usually
an interpersonal connection

taking out the rage.

To do that on children
who had nothing to do with this

shows what kind of man this was.

(Narrator) Despite a lack
of forensic evidence

at the murder scene,

police were able to build
a strong case

based on circumstantial evidence.

The house,
from a forensic standpoint

for criminal investigators,
was surprisingly clean.

11 days had passed

from the time...

that we know
that they were last...

known to exist, on February 4th.

We know that during that time,
Merritt went to the house,

based on his cell phone pings,

at least two to three times
by himself.

And then, ultimately,

during San Diego's
initial investigation,

they were able to get

a neighbour's
surveillance-camera footage

of a vehicle leaving
the McStays house on February 4th

in the evening hours

that we contended was consistent
with Merritt's truck.

(Narrator) Crucially,
Charles Merritt's phone records

also showed his cell phone
was switched off

the night the McStay family
disappeared.

Merritt had left Fallbrook...

his phone on...

pinging on towers headed
southbound on the interstate

to McStay's house,

suddenly goes off the grid,
off the network.

Whether it's powered off,
turned into airplane mode,

battery removed, whatever,

goes off the grid
for several hours

and then mysteriously popping
back on the radar,

or on the network,

after that several hours
of disappearance.

While it's circumstantial,

it's a significantly overwhelming
circumstantial case

that pointed only to Merritt,
no other individual.

He had the motive...

the loss of their cash cow.

Some people would characterise
jumping to murder

is a very far leap.

However...

when you look at an individual
like Charles Merritt,

one could imagine
he went to that house that night

to confront Joseph McStay...

(suspenseful music)

And the worst of the worst
got the best of him.

He turned to violence.

(Narrator) Despite the lack
of incriminating DNA

at the McStay's home,

the prosecution
were able to present

some forensic evidence to the jury.

What emerged in the trial

was that the detectives
had found...

his DNA in the Trooper

that had been parked
in the parking lot

near the border.

When detectives seize
the Isuzu Trooper

from the tow yard,

it's taken, and it's processed
at the time for fingerprints,

for DNA swabs,
inventory of the contents.

San Bernardino County tested those
and developed a DNA profile

consistent with Merritt...

on a couple different locations
in the car,

including the steering wheel
and the gear-shifter controls.

While it wasn't enough
to say he was a usual driver,

it was so overwhelming,

it was there
on the steering wheel.

He claimed to have never driven
that vehicle,

so why would his DNA be
on the steering wheel?

It was a circumstantial case,
though.

There was no blood in the house,

no indication of where
the actual killings took place,

although I guess
they could have taken place

at the site where the remains
were found.

(Narrator)
While there was mounting evidence

pointing to Charles Merritt being
responsible for the killing,

one huge question still hung
over the case.

How did they die?

What had lured them
out of the house

that night, February 4, 2010?

(dramatic music)

(Narrator)
Towards the end of the trial,

the prosecution presented
a picture of what they believed

happened that night.

(Britt)
There is a theory,

a hypothetical theory
of what happened in that house,

that at least the initial killing
of Joseph

may have been in a heated dispute

about the business
and being sidelined,

and he lost his cool and...

disabled Joseph in some way.

But when it comes to Summer

and Gianni and Joseph...

there is no explanation

or justification or mitigation

of why you would destroy

the skulls
of those three individuals,

other than they were witnesses

to your crime or crimes.

A defenceless four-year-old
and just turning three-year-old

bashed in the head
purportedly with a sledgehammer,

Summer's face shattered

into dozens of pieces

is a lot of deliberate anger
being taken out on that person.

The fact that he was able
to use a sledgehammer,

which is a weapon
that he would have had

to have been in close proximity,

shows the level of anger involved.

He wants to take revenge
on the man,

but he takes his anger out
on the entire family.

And that's the bit that's really
difficult to understand here.

(Britt) If you interpret
the evidence another way,

which was they were disabled,
removed from the house,

and then even killed
at the burial site,

you know, that's, what,
a 100-mile drive

from Fallbrook to the high desert

with four people being held
captive in some disabled state?

And then to only be murdered
at the gravesite

in sight of each other.

No matter how you looked
at the evidence,

those killings were wilful,
deliberate, and premeditated,

based on just the nature
of the injuries inflicted.

(Narrator)
On June 10, 2019,

a jury found
Charles "Chase" Merritt guilty

on four counts of murder.

Despite strong evidence
of embezzlement,

he was not charged or convicted
of any financial crimes.

Ultimately, Merritt is responsible

because he's the one
with the means, the motive,

and the opportunity
to commit these crimes.

No-one else did.

In fact...

he boasted to local news reporters

that he knows
that he's the last person

to see them alive.

Well, the last person to see them
alive is the actual killer.

It was an interesting turn
of phrase,

just like when he referred
to them in the past tense.

He very nearly got away
with murder.

It was only by a stroke of luck

that the bodies were found.

And in that time,

the family had simply disappeared.

He left no trace.

That shows that this was a man

who was very, very experienced.

He was a professional criminal.

He knew how to get rid
of evidence.

And he very,
very nearly did get away

with multiple murder.

(Scott) I think a case like this
sort of makes you question

whether a quiet neighbourhood
is really quiet.

How could something
like this happen

in a place like this?

I think that's what makes
this case resonate.

(Narrator)
On January 21, 2020,

San Bernardino Superior Court Judge
Michael Smith

sentenced Charles Merritt to death.

Merritt maintained his innocence

and continues to lobby appeals.

(child babbling)

(Summer) What is it, Chubba?
Oh, wow, Chubba.

(Joseph McStay) This is Chubba's

first Christmas present ever
in his life.

(Summer) Let's see, Chubba.
What'd you get?

(Britt) It's hard to determine
what motivated Merritt

to do what he did,

whether it's his greed...

Or desire to continue profiting
off Joseph and the business...

Or it's his greed

and having to make up the debt
that he found himself in...

or even that...

it spun so out of control,
he lost control.

Only he can explain that to us.

(child laughing)
(Joseph) All right, stay tuned.

(Narrator) Despite the successful
conviction of Charles Merritt,

the McStay murders
cast a long shadow

on many of those involved
in the case.

I work on a daily basis

with officers
who suffer with PTSD.

And there's many causes of that.

But I see often,

when there is
a particularly devastating case,

the impact that has on police.

And in this case,
you've got two children,

and the way
in which they were discarded

and then found,

I imagine that the police
on that scene

would have really been impacted
by that

and probably needed
professional help.

(Britt) So I first realised
the emotional impact of a case

was in this case,

and I had their crime-scene tech
from San Diego on the stand,

and we were just going
through pictures,

and we were going through the
processing of the Isuzu Trooper.

And I went to show her
a picture...

and I almost lost it,
and I couldn't... I just...

I had to stop, take a deep breath,

look away from the damn cameras
in the courtroom.

And...

I realised what it was.

I was showing her a picture
of Joe Jr's car seat

that was in the Trooper.

It was the exact same car seat
that I had put my kids in...

same model, same colour,
same everything.

That personal connection
was the first time ever,

and it was heart-wrenching.

Because we're not supposed
to make these things personal.

They're never personal.

But sometimes they are.

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