Forensic Files - Season 10, Episode 17 - Picture This - Full Episode | Forensic Files

[Music] most homeowners would prefer grass to a lawn full of weeds but the forensic scientists weeds can
tell a story with the help of a plant biologist and a new high-tech computer program
investigators solved the mystery of a young girl's murder [Music] weekends were typically busy in the
mauser household one saturday morning in 1995 as kathy mouser was leaving for work she reminded
her 14 year old daughter jenna that she was grounded for the weekend and wasn't allowed to use the telephone either
jenna was having some behavioral issues a lot of 14 year olds 15 year olds might
have those kinds of issues when they're growing up lots of pressure social pressures problems within the family
she was having such trouble that the family was taking her to counseling kathy returned home from work around 1pm
and as soon as she tried to open the door she knew something was wrong mrs mauser found the front door lock
which she said was unusual because usually there's there's somebody there and she was expecting jenna to be there
so the front door would have been unlocked jenna wasn't home and she hadn't left the note saying
where she went they just figured she was upset and she would basically just walked away you
know or she was just with one of her friends or yeah none of the neighbors saw jenna
leave or noticed anything suspicious when jenna's stepfather and brother arrived home several hours later
they searched the neighborhood and called all her friends but no one knew where jenna was
later that night the mousers called police to report their daughter missing the next morning the mousers learned
that the nude body of a teenaged girl was discovered in a ditch about 20 miles outside of town
the family identified jenna's body at the morgue the reality of her being murdered
rather than an accident or it didn't hit me i didn't understand really that that something like that
could happen in my life it was it was hard to deal with and and to it was just such an unfair
act and i couldn't couldn't understand it for a long time the coroner identified the cause of
death as strangulation there were other injuries as well in addition to the ligature
strangulation marks she also had evidence of blunt force injury to the head she had received a blow to the head
in the left forehead area and the left temple there were no defensive wounds and no signs of sexual assault the scalp
here is brown about 14 inches in length well the soles of the feet were clean in
this case and that indicates to me that she certainly was not standing up at the scene where she was
found and she certainly did not walk there the only other findings were some unusual marks on jenna's thigh
indentations that were made after death on a living person these fade very quickly
in this case these are postmortem pressure marks they don't tend to fade because the
the color comes as the blood leaks out of the vessels by gravity after death and it more or less outlines the area of
pressure and then it stays that way indefinitely until the body decomposes the mouser's telephone records yielded
the first clue despite the fact jenna was told not to use the telephone she called several
friends that morning yeah you should talk to him really senior well you'll see on monday
around 11 30 jenna's conversation with her friend ended abruptly hello jenna jenna one of the last people that she
speaks with says that the phone goes dead jenna doesn't call back the friend pages her a
couple of times jenna never calls back police found jenna's diary in her bedroom
which had an entry from the morning of her murder dear journal sorry i haven't written you
but i've been pretty busy things have been going pretty good at school except for the fact that guys
don't even know i'm alive half the time the diary expressed a specific interest in two boys
one was considerably older than jenna a boy she met at a local amusement park he was a young man about 18 or 19 years
old who was preying on children that were not age appropriate he was older than us um
not not the best kind of person that you'd probably want to want to be with but he
there was something that she saw on him that attracted her to him investigators needed to start checking
alibis and there was one that almost defied belief [Music] the mauser family had planned a
traditional funeral service for their fourteen-year-old daughter jenna until her friend sarah hollander told
them about a conversation the two once had about funerals we got on the topic of funerals and she did not want her
funeral to be a sad thing she doesn't like it when people are sad she loves to make people happy
she loves to make people laugh and so she definitely did not want her funeral to
to portray something that she wasn't about so the mousers allowed sarah to help plan the funeral service
one that was closer to jenna's wishes doug mouser took his stepdaughter's death particularly hard
he had raised jenna since she was two years old and treated her like his own she truly did have a great relationship
with him and loved him and he loved her he was very active in her life in the search for jenna's killer
investigators looked inside the mousers home but found no clues everything was basically in its place
nothing knocked over or anything to indicate that that jenna was fighting and screaming as she went out the door
this raised the possibility that jenna left home voluntarily what the sheriff's department did was
try and identify any boys she might have known or maybe if um boy she might have
left the house with even though she was grounded maybe she'd get in a car with them and drive away
police were able to identify the two boys jenna mentioned in her diary both had alibis for the day of the murder
so police turned their attention to the whereabouts of janna's family members jenna's 18-year-old brother jaron had a
solid alibi neighbors have him placed there for an hour hour and a half or so and that's the time period where jenna
disappears jenna's mother kathy was teaching an aerobics class at the local gym so her
alibi checked out too jenna's stepfather doug said he went to work for a few hours
when police tried to verify his alibi they discovered the security cameras at doug's office were turned off that day
when he went into the lab he's got to go through a security gate where all the cars that are coming in are cleared
initially the person who was in the booth at the time said they didn't remember seeing him or his car come
through doug mauser could give no description of the security guard and for a man who'd worked at the lab for a
number of years you would think he would know the security guards remember them be able to give some description he
could not so doug provided a second alibi that he bought lunch at a local fast food restaurant
coincidentally the restaurant's security cameras weren't working either if he didn't have bad luck he would have
no luck at all i can't really imagine you going into places that are supposed to have video cameras and none of them
record you it was sort of exasperating because of snafu's if you will you know we didn't have any tapes we didn't have
any solid stuff to show that he was there when police looked in doug's car they found no blood or any evidence
suggesting foul play and there was no evidence the car had recently been cleaned
but underneath the car investigators found something trapped in the undercarriage
there was a significant quantity of this dried plant material some of it very large pieces
and those were removed and analyzed later but had this plant material been there for
weeks it you certainly wouldn't expect to find such large pieces of it still attached to the undercarriage
could these dried weeds tell investigators anything about jenna's murder doug mouser told police he was the last
person to leave the house on the morning his stepdaughter went missing he claimed jenna was cleaning her
bedroom and he left there was no physical evidence that linked him you know like hair samples or dna or
anything like that there were no physical evidence none there was zippo zero nil nada
nothing yet investigators found some suspicious plant material underneath doug's car
which they sent to forensic botanist dr fred ruscha he identified the usual specimens you'd expect to find
underneath the car grass dirt and debris but he also found large quantities of yellow star thistle
a weed i saw the yellow star thistle and then i saw the small scraps that had been taken
off the body and i was able to compare that to material that had been collected from the area around the body and also
from the trees that were in the overstory above the canyon where the body was found
dr russia was looking for what botanists call diagnostic characteristics unique aspects of the plant that differentiate
it from others of the same species every plant has a life cycle and a life sequence
early in the season they look different than they do late in the season and prior to
death plant materials all species go through a sequence of developmental events dr ruscha discovered the star thistle
under doug mauser's car was identical in development to the star thistle found near janna's body
while this was significant it wasn't enough to tie doug mouser to the murder yellow star thistle is not a rare plant
it is an extremely common plant so in any given area of especially of northern california
you in low elevations a yellow star thistle could be there you can't show that the evidence that
was found underneath his car came from the crime scene it's too common in california and that
with the other flora under the car it shows that he's been off-road so he could have picked it up anywhere
investigators agreed so they turned their attention to the linear marks found on jenna's
thigh the marks were made by a man-made object they were clearly of a shape and appearance that would not
be normally found in nature while looking inside doug mauser's car detective bosma thought he found what
caused them the hair on the back of your neck stands up and you're going this could be the
mark of one of the marks on her leg but he didn't tell anyone about his discovery instead he sent photographs of
jenna's skin marks to gary robertson a pioneer in the field of photogrammetry to see what he thought might have caused
them robertson wanted to identify the exact size of the marks down to the micro millimeter
so he scanned every autopsy photograph of the marks which enabled him to create a three-dimensional model
we're extracting a measurement say from the left photograph extracting it from the right photograph and the computer
software merges that into a three-dimensional measurement or a model that we can extract and
do later judging from the size and shape robertson suspected that at least one of
the marks was caused by the top part of a seat belt buckle this was precisely what hans bosma
thought too but he wanted robertson's independent analysis well normally i don't have any
information so i wasn't aware of anything about the vehicle next robertson flew to modesto
california to conduct an experiment in doug mauser's car he wanted to try to recreate the same skin pattern that was
on jenna's thigh he placed a live model the same height and weight as jenna in the back seat of
the vehicle over the rear seat belt buckle it was a hatchback and one of the back seats was broken and
was kept flat the model remained in the same position for 15 minutes the time it would have taken to drive
from jenna's house to the dump site when the model was photographed robertson and bosma discovered
what caused the other mark on jenna's leg when he placed her in there the there's carpet on the back of that that
seat back because it lays flat so you have a nice carpeted area the carpet bead folds over as he pulls or pushes
her over that particular area and that carpet bead was what one of the indentations were on on her leg
just to make sure robertson put the model's pictures into his computer and compared them to the
marks on jenna's leg it was a virtual match the beating which would cause the imprint on the
model and on the victim's leg match precisely down to microns the width of the carpet
and the orientation in that matched as well also the length matched interestingly
the ripped carpet in the back seat of doug's car was unusual something you wouldn't find in other cars when he came
back and said you know it's a match boy we were just ecstatic we finally gonna be able to nail this guy now we
got him because now we can put jen in that car all the pieces fit together only one way and that's
showing doug mouser guilty of killing jenna they didn't feel right excuse me they didn't theorize
i'll say that on the screen i'd even say it in a courtroom they didn't have any theory other than he threw the body
he killed her and threw it over the side and that she was in his car because of the mark on her leg that's all there was
based on the forensic botany and photogrammetry doug mouser was arrested and charged
with his step-daughter's murder prosecutors wondered what motivated doug mouser to kill his
fourteen-year-old step-daughter jenna how can you possibly imagine someone doing something so horrible
i can't imagine it but it happens unfortunately all the time prosecutors found evidence that jenna
didn't always do what her parents asked she saw a counselor with some regularity
she had oppositional defiant disorder that she was very defiant very aggressive very
confrontational with family with parents the mousers telephone records provided a possible clue
hey what are you doing i just got back from the mall with annie on the morning of her death
jenna was on the telephone violating her parents rules his name's scott riley is
a senior prosecutors believe doug caught jenna on the phone lost his temper and struck her
hello jenna prosecutors believe doug's impulsive act of violence threatened his career he couldn't risk an allegation
that he had hit her struck her he was working at lawrence livermore lab and he had a security clearance so any kind of
a criminal conviction on his record would have been very difficult for him and put his job in jeopardy with jenna
unconscious and not sure what to do prosecutors think doug panicked and strangled her to death
he removed jenna's clothing to eliminate possible trace evidence when doug pushed jenna's body into the
back seat of his car he displaced the carpet the underside of the carpet and the seat
belt buckle left signature marks on her skin that wouldn't disappear since there
was no blood flow doug chose a dump site 15 minutes away pulled his car off the road which picked
up the bits of star thistle the same stage of development that was found on jenna's body
[Applause] [Music] prosecutors think doug simply got lucky when the security cameras at both his
office and the fast food restaurant weren't working but doug made a crucial mistake during his
interrogation he said he used his computer that saturday at the office but his employer found no evidence that
doug logged in they couldn't find any evidence whatsoever that he had done to his computers what
he said he did basically we caught him we caught him in a lie doug mouser was tried and convicted of
second-degree murder and sentenced to 15 years to life in prison he continues to maintain his innocence
ice for me this is the greatest failure of my life the only way i live with this situation
is that i did the best that i could i did everything that i could think possible
definitely uh jekyll and hyde personality there yeah one moment he's he's mr calm and cool and the next
moment he's seen something totally different i think she would be really happy to
know that that people love her so much to to fight to find the real answers to really what
happened to her and she would be happy to know that we haven't forgotten about her
the case against mouser was largely circumstantial but the photogrammetry helped convince
the jury photogrammetry was the key element and it was used to solve the case and
without photogrammetry this case would have gone unsolved [Music] [Music] [Music]
[Music] you

A Modesto, California teenager went missing. There was no sign of a struggle in her home, and police suspected she'd simply run away until her naked, bruised body was discovered in a ditch 20 miles away.

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

Forensic evidence links Doug Mouser to the murder of his stepdaughter Jenna, leading to his conviction.

Key points

The Mystery Unfolds. Forensic scientists and a plant biologist help solve a young girl's murder.
A Mother's Grief. Kathy Mouser discovers her daughter Jenna is missing, leading to a tragic revelation.
The Evidence. Investigators find suspicious plant material under Doug Mouser's car, linking him to the crime.
The Conviction. Doug Mouser is convicted of second-degree murder, maintaining his innocence.

Episode highlights

Episode quotes

It was hard to deal with, such an unfair act.

A mother reflects on her daughter's murder.

2:59WatchJan 14, 2022

Tension

75/ 100High tension

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