Housewife's Secret Affair with Neighbor's Teenage Daughter Ends in Murder

In this gripping episode of True Crime Case Files, we delve into the shocking murder of Helen Marquardt, a seemingly perfect housewife from Norman, Oklahoma, whose secret affair with a teenage neighbor turned deadly.

Episode Transcript

Speaker 1 (00:00):
Welcome to true Crime Case Files, where we delve into
the most shocking and perplexing crimes from across the country. Today,
we take you to Norman, Oklahoma, a seemingly quiet conservative suburb,
but behind closed doors, one woman's secret life led to
a grisly murder that left the entire community reeling. This
is the story of a devoted housewife whose hidden affair

(00:21):
with a neighbour's teenage daughter ended in a tragic and
violent death. Helen Marquart was forty two years old and
the picture of a perfect Southern homemaker. She lived in Norman, Oklahoma,
a quiet suburb known for its conservative values and close
knit community. Her life seemed like something out of a
family sitcom. A beautiful home, a loving husband, and three

(00:43):
lively triplets, Rider, Rifle and Ryan. Helen was heavily involved
in the community, especially at her children's school. She volunteered
for every event, from PTA meetings to bake sales. Helen
was also active in local charity work, often organizing food
drives and fund raisers for families in need. Her kindness
and warm personality made her a beloved figure in the neighborhood.

(01:06):
To the outside world, Helen seemed to have everything. Her husband,
Robert Marquardt, was a successful corporate lawyer, known for his
work helping major oil companies to find legal loopholes to
drill for oil in third world countries. The family often
attended church at First Baptist of Norman, where Helen led
a Bible study group for women. They were the kind

(01:26):
of family you'd expect to see on a Christmas card,
smiling and picture perfect, but beneath the surface, Helen was struggling.
Her marriage to Robert had grown cold and distant over
the years. Robert's demanding job kept him away from home
for weeks at a time, and when he was home,
he was often preoccupied with work. The couple's once strong
bond had weakened, leaving Helen feeling lonely and sexually unfulfilled.

(01:50):
She began to crave excitement, something to break the monotony
of her everyday life. In early twenty twenty two, Helen
found that excitement and most unexpected place, her seventeen year
old neighbor, Taylor Ronsley. What started as a friendly mentorship,
with Helen teaching Taylor how to act like a good
Christian lady, soon turned into something much darker. Their relationship

(02:12):
quickly escalated into a secret sexual affair, with Helen becoming
increasingly obsessed with the young woman. She was captivated by
Taylor's youth and energy, qualities that Helen felt she had
lost over the years. This affair became Helen's escape, a
way to fill the void left by her crumbling marriage.
In the days leading up to her death, Helen's behavior
became more erratic. She withdrew from her usual activities and

(02:36):
became more possessive of Taylor. It was clear to those
close to her that something was deeply wrong, but no
one could have predicted the tragic end that was about
to unfold. On the morning of June five, twenty twenty two,
Robert Marquart walked into his home in Norman, Oklahoma, after
a long overnight of the office. It was just after

(02:56):
seven am and the sun was already shining brightly through
the windows. The house was eerily quiet, which was unusual
given that his three children, Rider, Rifle, and Ryan were
normally up in getting ready for school. Robert expected to
find his wife, Helen, bustling about the kitchen making breakfast,
but instead he found the kitchen empty. Robert called out

(03:18):
for Helen, but there was no answer. As he climbed
the stairs to their bedroom, a sense of unease began
to settle in. When he reached the bedroom door, he
noticed it was slightly ajar. Pushing it open, Robert was
met with a scene that would honk him forever. Helen
was lying on the floor next to their bed, naked,
with a pool of blood around her head. She had
been shot to death. The room was a mess. The

(03:41):
bed was unmade, furniture was overturned, and shards of broken
glass were scattered across the floor. It was clear that
a violent struggle had taken place. Robert stood frozen for
a moment, his mind struggling to process what he was seeing.
Then panic set in. He rushed to Helen's side, desperately
trying to wake her, but it was too late. Realizing
she was gone, Robert grabbed his phone and dialed nine

(04:04):
one one, his hands shaking as he tried to explain
to the operator when had happened. The nine one one
call was frantic. Robert's voice was barely controlled as he
told the operator that his wife had been shot and
that she wasn't breathing. The operator tried to keep him calm,
but Robert was clearly in shock. When the police arrived
a few minutes later, they found Robert sitting on the

(04:24):
floor next to Helen's body, his face pale and his
eyes wide with disbelief. He was taken outside and placed
in a police car while the officers secured the scene.
News of Helen's death quickly spread through the neighborhood. Neighbors
who had seen the commotion began gathering outside the Marquart home,
whispering to one another as they tried to make sense
of what had happened. It wasn't long before local news

(04:45):
stations like KFORTV arrived on the scene, cameras rolling as
they reported live from the quiet suburban street that had
suddenly become the center of a grizzly murder investigation. The
Norman Police Department arrived at the mark Quarte home within
minutes of robert It's nine to one one call on
June five, twenty twenty two. Officer David Collins, a twelve

(05:05):
year veteran known for his calm demeanor, was the first
on the scene. He quickly assessed the situation and called
for backup. The quiet suburban street was soon filled with
police cars, their lights flashing red and blue, cutting through
the early morning calm. Detective Duane Yocum, a meticulous investigator
with a reputation for solving complex cases, was assigned to

(05:25):
lead the investigation. As the officers entered the home, they
were met with a chaotic crime scene. The bedroom was
in complete disarray. The bed was unmade, the mattress ascue
and several pieces of furniture had been knocked over. The
broken glass on the floor suggested a struggle had taken place.
Helen Marquett's lifeless body lay on the floor next to

(05:46):
the bed, a gunshot wound to her head the apparent
cause of death. Blood had pooled around her, staining the
beige carpet. A deep red. Detective Yocum surveyed the scene
with a practiced eye. She noticed the position of Helen's
body and the nearby object, making mental notes of everything.
The scene told a story of desperation and violence. Helen's
face showed signs of a struggle, with bruises visible on

(06:08):
her arms and legs. The ruined state indicated that Helen
had fought hard against her attacker. The murder weapon, a
small handgum, was found on the floor near Helen's body.
It was quickly bagged as evidence, along with the shards
of glass and several other items from the room. Forensic specialists,
dressed in white coveralls, methodically calmed through the bedroom, dusting

(06:29):
for finger prints and taking samples of the bloodstains. They
photographed the entire scene, documenting every detail that could later
be used in the investigation. Outside, Officer Collins interviewed Robert Marquardt,
who was still in a state of shock. Robert explained
that he had found Helen's body when he returned home
from work early that morning. He insisted he had no

(06:49):
idea who could have done this to his wife. As
the questioning continued, Robert's answers were slow and disjointed, reflecting
his disbelief and grief. Detective Yocum, while sympathy to Robert's
emotional state, knew that time was of the essence. The
first forty eight hours after a murder were critical, and
she was determined to gather as much evidence as possible

(07:10):
before any leads went cold. The investigation was just beginning,
but the scene in the Marquarte home had already provided
several clues that would guide the detectives in their search
for Helen's killer. Taylor Ronsley, the seventeen year old neighbor
and the first suspect in the investigation, was well known
around Norman, Oklahoma. She was a bright and independent young woman,

(07:31):
sept to graduate from Norman High School that month. Taylor
was popular among her peers, known for her rebellious streak
in a town where conservative values often dictated behavior. She
had recently been accepted to the University of Texas at Austin,
where she planned to study environmental science, a passion she
had developed during her year's volunteering at the local animal

(07:51):
shelter and participating in climate change protests. Despite her vibrant exterior,
Taylor's sexual relationship with Helen Marquart at ticket in a
dark turn. What began as a mentorship quickly escalated into
a secret, passionate affair that left Taylor feeling increasingly trapped. Helen,
who initially acted as a guide for Taylor in navigating
the expectations of their community, soon became a possessive and

(08:15):
controlling sexual partner, often asking Taylor to experiment far beyond
her comfort zone. Taylor's friends noticed a change in her behavior.
She had become more withdrawn, avoiding social gatherings and skipping
her usual hangouts like the local Starbucks where she and
her friends would often meet. When Detective Duane Yocum and
her team brought Taylor in for questioning, they were particularly

(08:36):
interested in her sexual relationship with Helen. The detectives knew
that Helen's possessiveness could have been a possible motive for murder.
Kayler's reaction during the interrogation was telling. She appeared nervous,
fidgeting with her hands and avoiding eye contact. Detective Yocum
asked Taylor about the nature of her relationship with Helen,
and at first Taylor was reluctant to say much. However,

(08:58):
as the questioning cantinued, she admitted that she and Helen
had been involved in a romantic relationship that had recently soured.
Taylor described how Helen had become increasing lyad erratic in
the weeks leading up to her death. She mentioned how
Helen would often call her at all hours of the day,
demanding her to drop everything to have sex with her.
Taylor also revealed that Helen had threatened to expose their

(09:20):
relationship if Taylor tried to end it Beast threats had
caused Taylor a great deal of stress, and she had
started to feel suffocated by Helen's constant need for control.
When asked where she was the knight of the murder,
Taylor claimed she was at a friend's house studying for
final exams. The detectives noted her alibi, but remained skeptical
given the tension in her relationship with Helen. Taylor's nervous

(09:41):
demeanor during the interrogation only heightened their suspicions. Detective Yoakum
pressed her for more details, but Taylor maintained her innocence,
insisting that she had nothing to do with Helen's death.
Despite her denials, Taylor's connection to the victim and the
strained nature of their relationship made her a key suspect
in the investigation. The detectives knew they needed to dig

(10:02):
deeper into Tailor's story to either confirm or rule out
her involvement in the crime. The next person under scrutiny
was Robert Marquart, Helen's forty six year old husband. As
a corporate lawyer specializing in helping oil companies find loopholes
to take people's land in third world countries for drilling.
Robert had a demanding career that often kept him away

(10:22):
from home. He worked long hours, frequently traveling for business
meetings and court appearances. In the close knit community of Norman,
he was known for his professional success, but also for
his distant, somewhat aloof demeanor. Unlike Helen, who was actively
involved in the community, Robert kept mostly to himself, focusing
on his career and leaving Helen to manage their home

(10:45):
and raise their three children, Rider, Rifle, and Ryan. Robert's
relationship with Helen had been strained for some time. The couple,
once seen as the perfect pair, had grown apart over
the years. Friends and neighbors noticed a shift. They no
longer attended events together, and when they did, there was
an obvious tension between them. Helen had confided in a

(11:05):
few close friends that she felt neglected and lonely in
her sexless marriage. She had mentioned how Robert's constant absences
had made her feel more like a single parent than
a partner in their relationship. On the night of Helen's murder,
Robert claimed he had been working overnight at his office
in downtown Oklahoma City. He told the detectives that he
hadn't noticed anything unusual when he returned home early the

(11:27):
next morning, only to find Helen's lifeless body. Detective Duane
Yocum and her team were interested in Robert's alibi and
his reaction to finding his wife dead. They questioned him thoroughly,
trying to gauge whether his grief was genuine or if
it masks something darker. During the interrogation, Robert remained calm
and composed, answering questions in a measured tone. He expressed

(11:50):
deep sorrow over Helen's death, but there was a detachment
in his demeanor that the detectives found unsettling. He admitted
that he and Helen had been having marital problems, but
insisted that he still loved her and would never have
harmed her. However, the detectives couldn't ignore the possibility that
Robert's strained marriage and Helen's affair with their neighbor's daughter,

(12:11):
killer Ronsley, could have provided a motive for murder. When
pressed about his whereabouts on the night of the murder,
Robert was adamant that he had been at work, presenting
time stamped emails and phone records as proof. While his
alibi seemed solid, the detectives were not entirely convinced. They
noted that Robert's profession gave him the skills and resources
to potentially cover his tracks if he were involved in

(12:32):
the crime. Despite his calm demeanor, Robert's strained marriage and
the coldness in his relationship with Helen kept him firmly
in the spotlight of the investigation. The detectives knew they
had to keep a close eye on him as they
continued to piece together the events leading up to Helen's death.
The third suspect in the investigation was Karen Ronsley, Taylor's
forty two year old mother. Karen was a single mother

(12:55):
who worked long hours as a nurse at Norman Regional Hospital.
She was known for her dedication to her job, often
working double shifts to make ends meet and provide for Taylor.
Despite her busy schedule, Karen had a reputation for being
a strong, no nonsense woman who cared deeply for her daughter.
Karen and Helen Marquart had been friends for several years.
Their friendship was initially built on shared experiences as mothers

(13:18):
and homemakers. However, as time passed, Karen began to notice
changes in her daughter's behavior. Taylor had become more secretive,
and her once close relationship with her mother seemed to
be slipping away. Karen suspected that something was going on
between Taylor and Helen, but she wasn't sure what. A
few days before Helen's murder, Karen confronted Helen about her suspicions.

(13:41):
The two had a heated argument in Helen's driveway, where
Karen demanded that Helen stop having sex with her daughter.
Karen was protective of Taylor and didn't like the idea
of her daughter being involved in anything that could harm
her future. The confrontation left both women angry, and Karen
left the encounter feeling uneasy. When Detective Duyn Yocum and

(14:01):
her team brought Karen in for questioning, they were aware
of the argument she had with Helen. The detectives asked
Karen about her relationship with Helen and why she had
confronted her. Karen, who was usually composed, showed signs of
stress during the interrogation. She admitted that she had argued
with Helen, but denied having anything to do with her death.
She explained that she was concerned about Taylor's well being,

(14:24):
and only wanted to protect her daughter from getting hurt.
The detectives pressed Karen about her whereabouts on the night
of the murder. Karen stated that she had been working
a night shift at the hospital and had clocked out
just before midnight. She provided time stamped records from the
hospital's time keeping system to support her alibi. Despite her
strong alibi, the detectives couldn't ignore the intensity of the

(14:47):
argument she had with Helen and the fact that she
lived so close to the crime scene. Karen's protective nature
and her proximity to the Marquhart home kept her on
the detective's radar. They continued to investigate her involvement, looking
for any possible link between her argument with Helen and
the events that led to Helen's murder. While Karen maintained
her innocence, the detectives knew they couldn't rule her out

(15:09):
just yet. The investigation into Helen's death was far from over,
and Karen's role in the case remained a critical piece
of the puzzle. On June twelfth, twenty twenty two, just
as the summer heat began to settle over Mormon, Oklahoma,
a breakthrough in the case emerged. It was mid morning
around ten AM when Detective Duane Yocum received a call

(15:31):
from a technician at a local electronics repair shop, tech Fix,
located on Main Street. The technician had been working on
a malfunctioning home security system brought in by a customer
when he stumbled upon something unusual several hidden video files
stored within the system's memory. These files contained footage that
had been recorded in the marquardt home, specifically in the
master bedroom where Helen Marquard's body had been found. The technician,

(15:54):
realizing the significance of what he had discovered, immediately contacted
the police. To Yocum and her team quickly arrived at
tech Fix to review the footage. The videos, which were
dated over several months leading up to the murder, provided
chilling evidence. The recordings revealed Helen engaging in a sex
relationship with Taylor Ronsley. What was more disturbing, however, was

(16:16):
that it became clear Helen had been the ones secretly
filming their sexual encounters, likely without Taylor's knowledge. The videos
not only confirmed the illicit affair, but also showed the
increasing tension between Helen and Taylor. In one of the
final recordings, made just days before the murder. Helen could
be heard threatening to expose their relationship if Taylor tried

(16:36):
to leave her. The footage painted a picture of a
sexual relationship that had turned toxic, with Helen growing more
possessive and Taylor appearing increasingly fearful. This new evidence was
a turning point in the investigation. The detectives realized that
Helen's murder wasn't just a crime of passion. It was
the tragic result of a relationship that had spiraled out

(16:57):
of control. The footage also provided crucial inns sight into
Taylor's state of mind leading up to the murder, suggesting
that she may have acted out of fear and desperation.
With this new evidence in hand, Detective Yocum and her
team returned to the marquardt home to search for the
hidden cameras that had captured the footage. They found several small,
discrete devices placed around the bedroom, further confirming Helen's role

(17:19):
in recording the videos. This discovery significantly shifted the direction
of the investigation. The detectives now had a clearer understanding
of the dynamics at play and began focusing more on
Taylor's involvement, leading them closer to the truth about what
happened on the night of Helen Marquardt's death. As the
investigation reached its climax, all eyes were on Taylor Ronsley.

(17:41):
The hidden footage discovered in Helen Marquardt's home provided the
detectives with critical evidence that pointed directly to her. On
June fourteenth, twenty twenty two, Detective Duane Yocum and her
team finally felt they had enough to make an arrest.
Taylor Ronsley, just eighteen years old, was a popular high
school senior who had once been full of promise. Known

(18:02):
for her outgoing personality and academic achievements, Taylor was the
kind of girl who seemed to have it all, but
behind closed doors, she was trapped in a toxic and
secretive sexual relationship with Helen, a relationship that had spiraled
out of control. Taylor's once bright future had dimmed under
the weight of Helen's controlling, manipulation and possessiveness. On the

(18:23):
night of Helen's murder, the tension between the two reached
a breaking point. The hidden footage showed Helen threatening to
reveal their sexual relationship be a sex stage she had
recorded if Taylor ever tried to leave her. This threat
was the final straw for Taylor, who felt cornered and terrified.
In a moment of panic and desperation, Taylor grabbed the

(18:43):
gun from Helen's nightstand and shot her. The crime scene,
with its overturned furniture and broken glass, told the story
of a fierce struggle that had ended in tragedy. Detective Yocum,
now confident in her case, moved quickly. At three pm
on June fourteen, the police arrived at the home Taylor
was inside, sitting on the living room couch with her mother, Karen.

(19:04):
The officers calmly explained the situation and placed Taylor under
arrest for the murder of Helen Marquart. Taylor, visibly shaken,
didn't resist. She seemed almost relieved, as if the weight
of her secret was finally being lifted. Karen, on the
other hand, was in shock. She had no idea that
her daughter had been involved in such a dangerous relationship,

(19:25):
and the reality of the situation left her speechless. The
arrest sent shockwaves through the community. Helen's family, especially her
husband Robert and their three children, were devastated by the news.
Robert had suspected that something was wrong in his marriage,
but he never imagined it would end in such a
horrific way. The Marquarte family, once seen as the epitom

(19:46):
of suburban success, was now shattered. In the days that followed,
more details about the toxic sexual relationship between Helen and
Taylor came to light, painting a complex picture of emotional
abuse and desperation. The community, which had an initially seen
Taylor as a promising young woman, began to view her
actions through a different lens, one that took into account

(20:06):
the psychological torment she had endured. Taylor's arrest marked the
beginning of a long legal process, one that would force
everyone involved to confront the dark truths that had been
hidden beneath the surface of their seemingly perfect lives. The
trial of Taylor Ronsley began in late November twenty twenty two,
capturing the attention of the entire Norman, Oklahoma community. The

(20:28):
courtroom was packed with spectators in media, all eager to
see how the case would unfold. The prosecution led by
District Attorney Mark Peters, a fifty year old, seasoned lawyer
with a reputation for being tough but fair, argued that
Taylor had committed cold blooded murder. Peters painted a picture
of Taylor as a manipulative young woman who, when faced

(20:48):
with the possibility of losing control over her secret affair
with Helen Marquart, chose to end Helen's life rather than
face the consequences. On the other side, Taylor's defense attorney,
Lisa Greene Troller, a thirty eight year old known for
her passionate advocacy for young clients, took a different approach.
Green Trawller argued that Taylor was a victim of Helen's

(21:09):
emotional and psychological manipulation. She presented evidence from the hidden
videos showing how Helen had increasingly pressured and threatened Taylor,
driving her to the brink of despair. Green Trawller contended
that Taylor's actions, while tragic, were the result of intense
fear and a sense of having no way out. She
pleaded with the jury to consider that torment Taylor had

(21:30):
endured in the months leading up to the murder. The
trial was emotionally charged, especially for Helen's family, who sat
in the courtroom every day listening to the details of
Helen's secret life and the events that led to her death.
Robert Marquart in particular, was visibly shaken as he heard
testimony about his wife's affair and the manipulative behavior she

(21:51):
had displayed toward Taylor. But triplets too young to fully
understand the proceedings were kept away from the trial, their
lives now forever changed by the loss of their mother.
After several days of testimony and arguments, the jury reached
a verdict on November twenty ninth, twenty twenty two. Taylor
Ronsley was found guilty of manslaughter, not murder. The jury,

(22:12):
influenced by the evidence of Helen's manipulation and Taylor's psychological state,
chose to convict her on a lesser charge. The judge
sentenced Tailor to ten years in prison, with the possibility
of parole after five years. The sentence was met with
mixed reactions. Helen's family felt the punishment was too lenient,
struggling to reconcile the woman they knew with the secret

(22:34):
life that had led to her death. Meanwhile, some in
the community sympathized with Taylor, recognizing the difficult circumstances that
had driven her to commit the crime. The trial's conclusion
left many a Norman reflecting on the hidden struggles that
can exist behind closed doors and the tragic consequences they
can bring. In the aftermath of the trial, the lives

(22:54):
of everyone involved were profoundly changed. Taylor Ronsley began serving
her life at the Mabel Bassett Correctional Center, a women's
prison in McLeod, Oklahoma, at just eighteen years old. Her
life had taken a tragic turn. Inside prison, Taylor enrolled
in counseling and educational programs, trying to rebuild her life

(23:14):
from the routins of what it had become. Her once
bright future full of promise, now seemed uncertain as she
faced the consequences of her actions. Helen Marquardt's family struggled
to move on from the tragedy that had torn their
lives apart. Robert Marquardt, who had once been a successful
corporate lawyer, found it difficult to return to his high
powered career. The revelation of his wife's secret affair and

(23:38):
the circumstances surrounding her death had left him shattered. He
took a leave of absence from his job, choosing instead
to focus on raising his children, Rider Rifle and Ryan.
The triplets, just nine years old, had lost their mother
in the most horrific way. Robert did his best to
shield them from the details of the case, but the
emotional scars ran deep. Karen Ronsley, his mother, also faced

(24:01):
an uphill battle. A dedicated nurse who had always worked
long hours to provide for her daughter, Karen was consumed
with guilt, wondering how she could have missed the signs
of her daughter's distress. She continued to support Taylor throughout
her incarceration, visiting her regularly and advocating for her early release.
The Norman community, once close knit and conservative, was left

(24:22):
in shock by the events that had unfolded in their
quiet suburb. Helen Marquard's death and the trial that followed
became a cautionary tale, a reminder that even in the
most seemingly perfect neighborhoods, dark secrets could be lurking beneath
the surface. Friends and neighbors who had once admired the
Marquette family now looked at their own lives, questioning what
might be hidden behind their own closed doors. Life in

(24:44):
Norman slowly returned to normal, but the memory of Helen's
tragic death and the trial that followed would never fully fade.
It served as a grim reminder of the hidden pain
and desperation that can lead to unimaginable consequences.