Forensic Files Season 11, Episode 39 - Fired Up - Full Episode | Forensic Files

[music playing] NARRATOR: Is it possible to commit the perfect crime? A house fire in Oregon came awfully close,
until a microscopic clue on a piece of pipe told investigators what really happened.
[theme music] NARRATOR: There's usually only one reason why people move to Gales Creek, Oregon.
LARRY MCKINNEY (VOICEOVER): Even though you're very close to Portland or within probably a half an hour of Portland,
you're out in the woods, away from everybody. It's less populated. It's a chance to get away.
NARRATOR: For Derrick and Roxanne Duehren, Gales Creek provided a much needed refuge
from their stressful careers in the computer industry. BARBARA CANNON (VOICEOVER): When they bought that property
in Gales Creek, that was more than my sister would have ever have dreamed of having.
That was her dream come true. LARRY MCKINNEY: And it also gave them enough room for Roxanne's horse farm.
BARBARA CANNON: She loved her horses. They were her balance in life, and she loved showing them.
She loved spending time with them. That was her downtime and her stress relief, I'm sure.
LARRY MCKINNEY: After living there for several years, the Duehrens started construction
on a 1,500-square-foot addition, but they would never see it completed. Late one Sunday afternoon, neighbors
saw a plume of smoke rising from the property. LARRY MCKINNEY (VOICEOVER): The fire
was actually reported by folks that lived more than a quarter-mile away. The house was not visible to any of the neighbors.
[bell ringing] NARRATOR: It took the volunteer fire department about 20 minutes to get there.
S. WILLIAM BENCH (VOICEOVER): When we come up to a fire and it's fully involved, that means that we visually
can see flames coming out of every opening, door, window. That usually means that it's been a period of time
before we've gotten there. NARRATOR: Derrick Duehren returned home from grocery shopping, and when he saw Roxanne's car,
he feared the worst. LARRY MCKINNEY (VOICEOVER): Derrick ran up towards the fire
and dropped to his knees and screamed that he believed that his wife was inside.
-Well, that's the worse thing that you can possibly hear, is that someone's inside.
You still have the sense that you want to try to get in there and possibly save their life.
NARRATOR: It took almost three hours to bring the fire under control. When they did, they found Roxanne's charred remains.
LARRY MCKINNEY (VOICEOVER): The body had been burnt horrifically. ROBERT BLETKO (VOICEOVER): Her remains
were little more than 35 pounds. They were so limited that the medical examiner was unable to determine the cause of death.
NARRATOR: Since dental records were useless in making a positive identification, the medical examiner used DNA.
LARRY LEWMAN (VOICEOVER): So what we did was take bone marrow material, submit it to the laboratory.
They got some samples from the parents and proved her identity by DNA. NARRATOR: Roxanne Duehren was only 34 years old.
BARBARA CANNON (VOICEOVER): From that moment on, you have a loss, and you're frightened and you're scared.
But it just seemed from there, it went into a bad dream that just turned into a nightmare.
NARRATOR: And that nightmare got worse when pieces of a handgun were discovered next to Roxanne's body.
Fire investigators wanted to know what started the fire that killed Roxanne Duehren.
Roxanne's husband, Derrick, had a possible explanation. LARRY MCKINNEY (VOICEOVER): Derrick
said it'd been a normal Sunday. They had awakened kind of late and he had made breakfast
for his wife, and it was just a lazy sort of day. But there were frozen pipes because of the weather.
NARRATOR: To thaw the pipes, Derrick said he turned on the clothes dryer in the basement
and left its door open to heat the room, then left to buy groceries. The dryer, however, used propane gas.
ROBERT MILLS (VOICEOVER): Propane is pretty dangerous like that. It lays down in the low areas and you get a lot of people
get hurt from that. NARRATOR: As a matter of routine, police asked Derrick for the store receipt
to prove he was shopping, and he willingly complied. ROBERT BLETKO (VOICEOVER): There was a receipt that
showed that he in fact had been at the store on the day in question. NARRATOR: But police were troubled
by the scratch marks Derrick had on his face. ROBERT BLETKO (VOICEOVER): His explanation
was that he was clearing debris that had fallen during the ice storm across the road that led up to his residence.
The explanation is in moving these branches, that he scratched himself across the face.
NARRATOR: The highly flammable propane gas clothes dryer was one possible cause of the fire.
Another possibility focused on the garage, where investigators found that the battery cable in Roxanne's car was disconnected.
LARRY MCKINNEY (VOICEOVER): The car was brought up as a possible origin of the fire,
that somehow a battery cable had caused a spark. NARRATOR: And the house was being remodeled.
Only the wall frames were up, which meant the fire spread easily. LARRY MCKINNEY (VOICEOVER): Forensic experts
retained by the state to examine the vehicle found no indication that would suggest to them that there was any type of arcing
that caused this fire to occur or start in the vehicle and then spread into the house.
NARRATOR: But investigators thought the laundry room was the most likely source.
And they found something unusual-- small pellet-like material near the clothes dryer.
-It all seemed to be in a small little pile, right near the origin of the fire. NARRATOR: At first, no one knew what this was,
or why it would be there. LARRY MCKINNEY (VOICEOVER): I thought about this for about three days.
And we had a cat at the time, and it wasn't until I had to change the kitty litter that I determined, hey,
that's a type of kitty litter. NARRATOR: The Duehrens had cats, but their cat litter box
was nowhere near the laundry room. Detective McKinney kept asking himself, why would cat litter be near the origin of the fire?
LARRY MCKINNEY (VOICEOVER): I went out and bought a bag of it and brought it back to my office,
and actually had it sitting in my cubicle. And trying to figure out why that would, you know,
would be there. NARRATOR: As he pondered this, a fellow detective took notice of the cat litter in McKinney's office.
LARRY MCKINNEY (VOICEOVER): He walked by asked me if I was going to start a fire.
That detective worked burglary cases and really didn't know what kind of a case I was involved in.
And I said, why would you ask me that? NARRATOR: The detective, a former Boy Scout,
said soaking cat litter with gasoline was an old trick to help start campfires. LARRY MCKINNEY (VOICEOVER): It was in an old "Boy's Life
Magazine" that he had learned about it. NARRATOR: A background check revealed Derrick Duehren was
an Eagle Scout in his youth and might have known about this method of starting fires.
But investigators found no clear evidence of arson. Arson dogs did not detect the presence of accelerants
anywhere in the house, including in the burned cat litter. In terms of possible foul play, Derrick and Roxanne
had no known enemies and, by all accounts, had a happy marriage. But the Duehrens owned a handgun,
which was found near Roxanne's body. Police had to consider if this could have been suicide or murder.
The handgun found next to Roxanne Duehren's charred remains raised new questions about her death.
The medical examiner x-rayed the remains, but the body was so badly burned, it was impossible to find evidence of a gunshot wound.
There was no ash or soot in Roxanne's lungs and no carbon monoxide in her blood, which meant--
[bang] -She was not breathing when the fire started. LARRY LEWMAN (VOICEOVER): This, to me, is a homicide.
There's no other reasonable explanation as for why she is a healthy young woman who's dead before a fire starts.
NARRATOR: And there was blood in Roxanne's airway. LARRY MCKINNEY (VOICEOVER): She had obviously died
by some sort of violent means, because she had aspirated blood. And from my past experience, people that aspirate blood
means that there was some sort of horrific injury to their face or head, and their last breaths
are taking in blood, rather than air. ROBERT BLETKO (VOICEOVER): Roxanne Duehren
did not die in the fire, which means somebody caused her death. NARRATOR: But how had the fire started?
Investigators turned to the propane-powered clothes dryer. Derrick Duehren said he thought the dryer started the fire,
because when he left the house, the dryer was running. But investigators discovered that the propane gas line
into the dryer was disconnected. Had firefighters done this while extinguishing the blaze?
BRUCE WONG (VOICEOVER): Firefighters are not concerned about destroying evidence.
They're there to put the fire out and to save human life. NARRATOR: Since the disconnected hose had a threaded metal end,
a forensic metallurgist found no evidence that firemen created the disconnection.
BRUCE WONG (VOICEOVER): Because if the threads-- once they lock in, in order for them to thread,
they'd have to strip it to pull out. These threads did not show that characteristic.
NARRATOR: Using a metallurgical microscope known as a metallograph, Bruce Wong saw evidence of oxidation
on the threads. BRUCE WONG (VOICEOVER): What I see there tells me that this pipe was open at the time of the fire,
that it's sufficiently open at the time of the fire so that the deposit could occur.
NARRATOR: Also on the pipe, Mr. Wong saw tiny brass beads sitting on top of the oxide on the threads
of the metal fitting. This formed when the brass fixture melted and fell through the air, forming these tiny beads
before landing on the fitting. This was further proof that the fitting was disconnected during the fire.
ROBERT BLETKO (VOICEOVER): It indicated that the connection was open, which would indicate that the fire
was deliberately set. -Derrick told me that the dryer was running, and it couldn't have been running,
because it was not connected at the time. And that was a provable lie. NARRATOR: Fire investigators now made
their official determination. The fire at the Duehren house was arson. LARRY MCKINNEY (VOICEOVER): And all of a sudden, everything
starts making sense, and you fall into that-- that area that you can actually follow what happens then.
It makes sense and you can forensically prove that. NARRATOR: But what was the motive?
Roxanne's family revealed the couple argued about money, particularly the money Roxanne was spending on her horses.
LARRY MCKINNEY (VOICEOVER): They had a horse barn built, a riding arena. She was taking what's called cutting lessons for-- I believe
they would cost $300 per lesson. NARRATOR: Investigators also learned that Derrick's job was
going to be transferred 150 miles away. That would mean selling their dream home and relocating,
something Roxanne did not want to do. BARBARA CANNON (VOICEOVER): I think that Roxanne said to him,
Derrick you go rent an apartment or we'll buy you someplace up there, and then you come back on weekends.
I don't think my sister wanted to move. I think that she voiced that probably pretty clearly to him.
And I don't think he liked it. NARRATOR: Investigators say Roxanne's defiance was too much for Derrick.
It was at variance with his vision of a perfect life and a perfect marriage. LARRY MCKINNEY (VOICEOVER): In talking to friends, coworkers,
everyone that I could possibly talk with, I could not establish a specific motive.
I had my suspicions that it was probably because Roxanne was beginning to stand up for herself.
According to her friends, she was starting to become more independent, which Derrick would not like.
BARBARA CANNON (VOICEOVER): Derrick wasn't going to get his way, and he was going to do
whatever he had to do to get his way. And there was nobody that was going to stand in his way,
and that included his wife. NARRATOR: When questioned by police, Derrick denied setting the fire and claimed
he would never have harmed his wife. Would this tiny spot on his jeans prove otherwise?
The medical examiner ruled Roxanne Duehren's manner of death as homicide, since she was
dead before the fire started. What he didn't know, however, was the cause of death.
But the fatal fire was determined to be arson, and Roxanne's husband, Derrick, became
a potential murder suspect. On the jeans he was wearing the day of the fire, investigators noticed a small spot.
LARRY MCKINNEY (VOICEOVER): I asked him specifically if it was blood, and he told me no, it was mud.
NARRATOR: A phenolphthalein test proved Derrick wrong. The spot was blood, and the subsequent DNA test
proved it was Roxanne's blood. For police, this made perfect sense. They never believed Derrick's explanation for the scratches
on his face. LARRY MCKINNEY (VOICEOVER): I know what scratches from brush would look like, and this was not a scratch from brush mark.
This was-- this appeared more to be fingernail scratches. ROBERT BLETKO (VOICEOVER): Derrick Duehren
had lied about how this fire occurred, how the scratches on his face occurred, how the blood on his pants came to be there.
NARRATOR: With proof of arson, his wife's blood on his clothing, and the apparent fingernail scratches
on his face, Derrick Duehren was arrested and charged with arson and murder. But Derrick was convinced he'd never spend a day in jail.
ROBERT BLETKO (VOICEOVER): Derrick Duehren thought he was smarter than everyone else.
He was sending emails to friends of his, coworkers at Intel, updating them on the trial as it was going along,
talking about in terms of being a chess match and his view of how that chess game was going,
and his expectation that he would be acquitted. NARRATOR: Prosecutors believe that Derrick and Roxanne got
into an argument on the afternoon of her death-- an argument that turned violent.
-I'm not getting rid of my horses. I'd rather get rid of you first. NARRATOR: Blows were struck with enough force
for Roxanne's blood to land on Derrick's jeans. She tried to defend herself and scratched his face.
Prosecutors believe he killed her, although they're not sure exactly how. Realizing he needed to cover up the crime,
he decided to burn down the house. I First, he went outside and turned off the propane gas,
then disconnected the supply line to the dryer and set fire to the gas-soaked kitty litter.
When he went back outside to open the propane valve, the gas would have produce a blowtorch effect,
burning hotter than natural gas and immediately igniting the material surrounding it.
Prosecutors believe that Derrick went shopping to establish an alibi. But not all of his time was accounted for.
ROBERT BLETKO (VOICEOVER): There was a discrepancy in Derrick Duehren's timeline, with respect to the receipts
that he obtained at the various stores. He could account for about an hour to an hour and a half of his time,
and it would appear that he would have had to have been gone well in excess of two hours based upon his initial comments
of when he left and when he returned. NARRATOR: Since the fire almost completely consumed
Roxanne's body, no one knows exactly how she died. ROBERT BLETKO (VOICEOVER): The jury
was unable to make a determination on the charge of murder, unable to decide. They did not find Mr. Duehren not guilty of murder.
They simply said, we are unable to come to a decision. NARRATOR: As a result, Derrick was only
convicted of arson and first-degree manslaughter. He was sentenced to 10 years in prison.
ROBERT BLETKO (VOICEOVER): Manslaughter in the first degree is defined under Oregon law
as recklessly causing the death of another human being under circumstances manifesting extreme indifference
to the value of human life. -Did Derrick think he get away with this? Absolutely.
Absolutely. Derrick thought that he could be smarter than all of them. His ego was that big.
And those people were beneath him. NARRATOR: Investigators say this case proves that no matter what
someone does to cover his tracks, something always remains behind. S. WILLIAM BENCH (VOICEOVER): People
do think, when they start a fire, that it's going to burn up everything and destroy
all evidence that they did it. And that's a fallacy that we like people to believe,
because we go back in as investigators and pretty well find out what caused the fire.
ROBERT BLETKO (VOICEOVER): The fire in this case was so severe that it destroyed a lot of the type
of evidence that you might normally find at a homicide scene. However, the fire itself creates evidence.
And in this particular case, the fire itself, and how it started and where it started, became crucial evidence
in the prosecution. -They always get caught in the end. Sometimes it takes a while, but they get caught.
LARRY MCKINNEY (VOICEOVER): This case was based almost exclusively on forensics, even though I like
to think that I had something to do with it. But in actuality, in this case, it was forensics that found him guilty.
[theme music] [music playing]

In 1996, Derrick Duehren returned to find his Oregon home burned to the ground. His wife's charred remains were later found in the rubble. Investigators set out to determine if it was an unfortunate accident or murder.

Forensic Files is the longest-running true crime series in television history. Evidence and interviews with experts help solve real crimes, disease outbreaks and accidents around the world.

Brief Summary

A house fire in Oregon leads to the discovery of murder and arson by Derrick Duehren, resulting in his conviction for manslaughter.

Key points

Unraveling the Mystery. Investigators find a clue that suggests foul play in Roxanne's tragic death.
The Fire That Changed Everything. A house fire in Oregon leads to a shocking discovery about Roxanne Duehren's death.
The Arrest. Derrick Duehren is arrested after evidence points to him as a suspect in his wife's death.

Episode highlights

Episode quotes

Is it possible to commit the perfect crime?

NARRATOR's opening question

0:06WatchJan 20, 2022

Tension

80/ 100High tension

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