(tense music)
(siren wails)
(tense music)
- [Narrator] Every suspect accused of a crime
has the right to remain silent.
Many agree to be interrogated anyway.
But they can stop the interview at any moment,
making it a race against time.
Justice hangs in the balance.
(tense music)
- On June 11th of 2013,
the front desk received an anonymous tip
from an individual saying they were suspicious
of a couple death-related incidents
and an incident where a young woman was hospitalized
and was also feared that she was going to pass away.
He was suspicious
that the mother of the home, Diane Staudte,
could have been involved in the deaths of her husband,
her son, and now the grave illness of her daughter.
(siren wails)
The doctor I spoke with said
they had performed numerous tests on Sarah
and they all came back as negatives.
Her condition was very dire
that it was expected that Sarah was not gonna survive.
However, the subjects involved
in her care all gave me the same story,
that they were suspicious of Diane.
They said Diane laughed and joked with people
and was not acting
how they thought a normal mother would act.
And a doctor said,
kinda based on the unknown nature of Sarah's illness,
he was suspicious
that it could possibly be a poisoning case.
(tense music)
I began to do some internet searches on the family,
looking at social media accounts,
just whatever was out there.
I found out the Staudte family consisted
of Diane, the mother.
She was very active in church
and she also had been a nurse for a long time.
Mark was a stay-at-home father
and they had four children.
They had Shaun, who was the oldest, Rachel, and then Sarah,
and then they had a younger daughter as well.
I also learned that a year earlier,
Mark Staudte passed away at the age of 61
of an apparent heart attack.
And then it was not long after when his son, Shaun,
who was only 26 years of age, passed away.
The medical examiner's office determined Shaun's cause
of death was sudden death in epilepsy.
The timing of the incidents was strange
with all of them being so close together
and then with Sarah and Shaun both being so young,
I really wanted to find out what was going on
in the Staudte home.
(gentle music)
- When Mark and Diane got married,
Mark invited me to be the best man at his wedding.
Mark was 4 1/2 years older than I was,
so Mark and I were fairly close.
When he got into music,
it really started taking over his mind
and where his thought processes were going.
(gentle music)
The first time I heard him, I was blown away.
♪ Thinking of the lady
♪ Who one day will come a wife ♪
♪ Is that you
Then he was actually doing live gigs
around the Springfield area
and was actually making some money.
And he seemed to be happy with that.
When Mark died, I was very sad.
I'd lost a friend, someone to talk to music about.
And then his boy, Shaun, several months later died.
It was a lot.
(melancholy music)
- Shaun, by all accounts, was a good kid.
He just was an autistic child that may have not have acted
like what many would consider normal.
But according to Shaun's teachers,
he was a very good student.
Shaun would read a textbook front to back
and his memory was so good
that he could recite facts throughout the textbook.
- Shaun's death, it did seem kind of strange
being so close to Mark's passing.
I was given the impression it was just an accumulation
of prior medical issues caught up with him and that was it.
(tense music)
- Diane told officers
that her husband had been ill for several days.
And that on the day of his passing,
he had actually had several seizures.
The officers questioned why she didn't take him
to the hospital or call an ambulance,
and her response was that Mark just refused to go
and so she allowed him to stay at the home.
- When we examined Mark's body,
there was some blood around his mouth.
I asked the medics on scene
what that may have been caused from
and was told that Mark was intubated
and could have been from that.
I had a problem with the fact that she didn't call EMS.
I was told that Diane was a registered nurse.
So a medical professional should probably know better
and insist on Mark going to the hospital
after he had had three seizures that day.
It was a complicated situation,
but there was no evidence
that anything nefarious had occurred at the residence
to contribute to his death.
(tense music)
- Shaun's death was just a few months after Mark's.
Both had been described as having flu-like symptoms,
being sick for a while leading up to the death,
and then both were noted to have blood around their mouth
at the time they were found.
I had all these suspicions that were building and building.
The problem, however, was
is that in all of the incidents,
when you actually looked for the poisoning
or what could be causing this, there was just nothing there.
I brought up the possibility of poisoning
and the doctor told me that everything that had been tested
was all negative.
However, he said that it could be very difficult
to determine if there was something in their system
without exactly knowing what it was
that they needed to look for.
And he also informed me that if something were to come up,
that Shaun's tissue samples were still being held
and that there could be further in-depth analysis
to try to discover if this could be a poisoning.
It was troubling, one, because of Sarah's condition,
but also because of,
there was still two other children in the home.
There was Rachel
and then they had a younger daughter as well.
I felt that I needed to act,
and so at this point, Diane became a focus
of my investigation.
(tense music)
Prior to bringing her into the interview room,
she was just very calm, very stoic,
but after putting her in the interview room,
I noticed she almost immediately clamped up.
She raised her legs and she put her hands together
and acted almost as if she was praying,
which I thought was very strange.
I decided to take a very gentle and soft tone
and I had to walk a very fine line
in terms of, is this individual a victim or a suspect?
Because I truly did not know at that point.
- At this time,
it was full belief that Sarah was not gonna survive.
The doctors could not figure out what was going on.
Her organs were shutting down.
And Diane was just so calm,
did not appear to be concerned whatsoever.
It really was just another alarm bell.
(tense music)
- I was told by my nieces that Sarah was in the hospital,
not doing very well, was in ICU.
And I thought, what's going on?
I had never really heard
of any specific medical issues regarding Sarah,
so it was a mystery to me.
(tense music)
- Diane never asked anything at all
about why I'd wanna speak
with her about her sick daughter.
I mean, the police department normally doesn't come
and ask somebody to speak with them
about an illness for a child.
So for her to not have any questions from the very get go,
it was a point that raised some flags.
- Diane makes a real odd laugh at that point.
And nervous laughter is,
it could be the characteristic of somebody
that's trying to be deceitful
or trying to mask some kind of emotion.
- In terms of working suicide incidents,
I don't know that I've ever come across one
where somebody's taken a cleaner and definitely not soap.
It seemed very disingenuous
and it just essentially cemented my suspicions
that this could be a very bad situation
in terms of her being involved.
(clock ticking)
One technique that I used a lot with Diane
were awkward silences and awkward pauses.
It was just to try to
elicit any type of information from her.
And it was extremely difficult because Diane just sat there
and we just stared at each other.
(tense music) (clock ticking)
When I brought up to her the fact
that Shaun's tissue samples had been saved,
she didn't need to say anything at that point
because I could read it on her face that she was worried.
(tense music)
- I didn't know what to expect in terms of the test results,
but I told her that because I wanted to see her response.
I wanted to see her reaction to it and it almost froze her.
I was very worried.
Is that gonna be something where she goes, "Oh my gosh,
I'm no longer speaking with this detective"?
Is she gonna lawyer up?
So I had to try to come up with something
that would get her to speak more openly with me.
I was trying to almost portray her as the victim,
that maybe Mark was doing things
that he should not be doing and I could sympathize with her.
And so I had to continue to try to build her up
and to continue with the victim narrative.
- I started down a theme of just her being pushed so far
that she just couldn't take it anymore.
I began to move closer to her just
to give her the sense that I was there to try to help her
and get her story out that she wanted everyone to know.
(tense music)
- When Diane told me
that she could have taken Sarah to the ER sooner,
I thought that she was getting ready
to put it all out there.
Diane knew how sick her daughter was and she waited
and shes now admitting to me that she waited.
It sounds cliche,
but I was beginning to realize I was speaking
with a truly evil person.
(tense music)
(clock ticking)
(ominous music)
- It was a huge adrenaline rush to hear her mention antifreeze
because up to that point in the interview,
there was nothing that made any sense
about what could have happened to Sarah.
The excitement that is going through me,
it's kind of indescribable.
However, I have to do my best to not let that show.
I don't want her to see any kind of change in me
that would shut her down.
- My heart was pounding.
She calmly said, "I didn't know what else to do."
And I wanted to get up and jump and scream
and hug the other detectives
that were involved with this, you know,
knowing that we are gonna have some kind of resolution.
But I cannot let her see that
because even though now is the confession,
there's still a lot more information
that I've gotta get from Diane.
(ominous music)
(tense music)
- Even with Diane admitting
that she had administered the antifreeze,
there was still a lotta questions.
I wanted to know how, when, how often, the dosages.
(dramatic music)
- Formality. - Yeah, it is.
I did not arrest her for homicide at that point
because we still have no physical evidence
and there was more information I wanted to obtain
from Diane going forward.
(tense music)
(insects chirring)
It was noted to me that out in the garage on a workbench,
that there was a bottle of antifreeze
that was right next to a six pack of Coke.
It's just set up right out in the garage almost
as if it's getting prepared for the next go around.
Then one of our crime scene investigators told me
that I probably should respond to our evidence room.
So I immediately went there and he showed me a diary
that had been located in Diane's bedroom.
But it appeared to be that of Rachel's.
It was just another twist in the case
that you thought there's no way there can be more.
(dramatic music)
(suspenseful music)
- [Reporter] She did it with antifreeze,
adding the chemical to Mark and Shaun's drinks,
virtually undetectable in taste,
making them sick until their organs failed.
- I got a call saying Diane has just been arrested.
After I hung up, I was furious.
Knowing all of the steps she had to take
to pull these murders off really made me consider
what sort of devious mind she had to have had
to make that happen.
(tense music)
Diane was adamant that Rachel had nothing to do with it,
even made a statement to me that Rachel
would not hurt a fly.
But I had to find out from Rachel exactly
what her involvement and knowledge in the case was.
- Inside the diary,
there was an entry that was written long before the passing
of both Mark and Shaun where Rachel indicated
that she knew that both her father and brother
were going to be passing away.
And when she looked at that, she turned white.
It was almost if she had seen a ghost.
- She was just very matter-of-fact.
And the look on Rachel's face, it was extremely sinister,
just void of emotion.
And it was very eerie.
After Rachel was arrested,
my partner searched Rachel's purse
and inside the purse was another journal.
And inside it, I found a poem that stated
that, "Once upon a time there were six.
Now there are three.
Only the quiet ones are left."
(ominous music)
During the court proceedings,
there was a deal that was struck with Rachel
that she would testify against her mother.
The deal was essentially to give Rachel the possibility
for parole after approximately 40 or so years in prison.
Diane also ended up taking a plea deal.
Diane's agreed sentence was that the death penalty
would be taken off the table
and that she would serve life in prison
without the possibility of parole.
(pensive music)
- Sarah went through indescribable pain
and trauma from this.
And based upon all that,
she's confined to an assisted-living-style facility.
(melancholy music)
For someone like Shaun that really did not have a lot
of connections in the outside world,
his family was what he had.
They were the nucleus around him.
Shaun was a good kid.
He was an intelligent young man
and he did not deserve to die.
(bright guitar music)
- I still connect with Mark through music.
♪ How well I remember
- I always enjoy listening to Mark's songs.
I sing along with them
and wish that I'd had an opportunity while he was alive
to do something with those.
Mark was a good man, a good musician,
taken away far too young.
If there was one last thing I would say to Mark,
it's just, I miss you, bro.