Dateline NBC

Secrets in Pleasant Prairie

November 29, 2023 41m
The investigation into the poisoning death of a Wisconsin mother takes a surprising turn when detectives learn she wrote a letter just days before her death pointing to a possible suspect. Andrea Canning reports.

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Tonight on Dateline. This was a very cold, calculating plan.
This innocent, kind, loving woman. Those two boys were everything to her.
Just imagine all that Julie lost. Julie Jetson was found covered with a blanket on the bed.
You've got a suspicious death. Is it a homicide? Is it a suicide? We just didn't know.
One of the things the police learned, Julie had an affair. Correct.
She reported having pornographic pictures left outside the home, like on the car or in the garage. These photos are showing up at the office.
They're phone calls, heavy breathing. Somebody was stalking her, harassing her.
Who would harass a couple like this. We had talked about potential suspects.
Nobody, Nobody deserves what she went through. She wrote a letter.
She said, if something happens to me, please hand this to the police. She predicted her own death.
She did. Essentially talking from her grave.
I want Julie's voice to be heard. A young mother dead in her bedroom.
Was it murder? The biggest clue of all was one she left for investigators. I'm Lester Holt, and this is Dateline.
Here's Andrea Canning with Secrets in Pleasant Prairie. It was that magical time of year in Kenosha County, Wisconsin.
Nestled along the shores of Lake Michigan, in a village called Pleasant Prairie, colorful lights twinkled and Christmas carols filled the air. But in a house a block from the lake, there was no holiday cheer, only the eerie sound of a phone off the hook.
It was late afternoon, December 3rd, 1998. 40-year-old Julie Jensen, a wife and mother of two young boys, wasn't breathing.
Julie's husband, Mark, found her in bed under the covers. EMT Dave Wilkinson was at home when he got the call that a woman was in trouble.
You hop in your truck and... And we go to the house where we find our patient.
We're here at the Jensen home. Responding officers were already on the scene.
We were called this afternoon for a death investigation. They were allowed in the house by Mark Jensen.
Barry Olilla is a captain with the Pleasant Prairie Police Department. He directed them to the bedroom where Julie Jensen was found.
The EMT found her lying in bed as if she was sleeping, but he knew it was too late to save her. There's something different about the way her face, her body looked.
It wasn't peaceful. He could tell Julie had been dead for a while, but had no idea how she died.
You don't see anything obvious on her, like a gunshot wound or a knife wound, correct? Correct. There wasn't that obvious trauma that we associate with a violent death.
That was odd to you? Yeah. If it's a drug overdose or something like that, I would expect to see something drug paraphernalia around.
We didn't have that. It was just very unusual circumstances.
Her husband explained to the police that he came home after picking up their two boys from school and found Julie unresponsive. Did Mark have any idea of how she might have died? Mark Jensen explained that Julie had been taking some medication

and she wasn't feeling well for a few days prior up and including this day.

The police did find medication on the kitchen counter.

Mark told them it was an antidepressant Julie had just begun taking.

He said Julie had been suffering from depression for the last several months.

She'd lost her appetite and was having trouble sleeping. How was Mark behaving? It appeared that he was distraught and concerned.
Meanwhile, in the next town over, Bob Jamboyes, the Kenosha County District Attorney at the time, was out with his wife Beverly at a black tie hospital fundraiser. Bob had a tux and I wore a, and we went to the ball.
So you're having a nice evening. Yeah, and Bob got paged.
I go out to my car, and I call the Pleasant Prairie Police Department. And then he came back, he said he had to leave.
Beverly stayed at the gala, while Bob rushed over to the Jensen home. As soon as I saw Julie Jensen's body, I could observe that the position in her body was the way her arm was spread out underneath her.
I said she was rolled into that position. Nobody goes in that position naturally of their own accord.
The DA found that suspicious. He wanted the police to search the house, but there was a problem.
At this juncture, we don't have sufficient probable cause to support a search warrant. Jambois had an idea.
If it worked, he wouldn't need a warrant. So he went looking for Julie's husband.
An officer was watching the Jensen boys, 3 and 8 years old, while family and a police chaplain consoled Mark. I introduced myself, and I said, you know what, we have to do what's known as a full-fledged death scene investigation.
Will you agree to give us consent for us to search your residence? So he said, yes, we could have consent. Investigators began gathering evidence and noticed the family had a home computer.
In 1998, they were still considered a luxury. I said, we're going to be taking that computer.
This is the first time I'd actually seen a computer in the home at a crime scene. As they continued to search, investigators learned something potentially crucial to the case.
It turns out local police were quite familiar with Mark's wife. Our officers had a relationship with Julie Jensen.
They knew each other on a first-name basis based on the number of calls that she placed to our agency. Julie had been calling the Pleasant Prairie Police Department for years to report harassment, repeated hang-up calls to her and her husband.
And even more frightening, she said they'd found pornographic pictures planted at Mark's office and outside of their house. Your prosecutor's senses must be going off given that the police had been there so many times.
Yeah, prosecutors don't believe in coincidences. The DA had a hunch this was no accident.
Could the disturbing harassment be linked to Julie's death? A secret was about to be revealed. Julie had admitted to having an affair.
And as the investigation unfolded, an explosive piece of evidence would surface too.

If something happens to me, please hand this letter over to the police. District Attorney Bob Jamboyce was stumped.

Julie Jensen, a young mother, was dead. But why and how? When her autopsy report landed on his desk, he scoured it for answers.
What does it tell you about cause of death, manner of death? To be determined, not determined. So I don't know the cause or manner of death after the autopsy.
So Jamboys and detectives from the Pleasant Prairie Police Department turned their attention to finding out more about Julie. They learned she was born in Kenosha, Wisconsin, not far from where she died.
One of six children, she was the only girl surrounded by brothers who adored her. She was an angel of a person, and I don't say that about many people.
And that's not just because she was my sister, it's because it was true. It was a loving family, and it was a Christian family that she grew up in.
Leslie Ferraro was one of Julie's closest childhood friends. They grew up just a few blocks apart.
She was a sweetheart, just a very good human being. I mean, she was fun.
Julie played violin, as did I. She was very smart, very good at school, very conscientious.
The DA learned Julie and Mark first crossed paths when they worked together part-time at Sears. She met Mark in the mid-early 80s.
Then they started dating, I think, when they were in college. After Mark graduated, the couple tied the knot in the spring of 1984 and eventually settled in the upscale Carroll Beach neighborhood of Pleasant Prairie, Wisconsin.
Mark was a successful stockbroker. Julie had also worked in the financial world.
She was an administrative

assistant in a stockbrokerage firm, but she had a series seven license, which you have to have in order to place orders for customers. In 1990, they welcomed their first son, David.
Five years later, Douglas came along. Mark was known around town as being quiet, but also ambitious.
He soon made a for himself at his firm, while Julie put her career on hold.

She was a stay-at-home mom, and she was a babysitter. Looking for help with the case, the DA turned to his wife, Beverly, an experienced attorney.
What did you learn about Julie Johnson? Well, I learned that she was a wonderful mother, that her children were everything to her. Her license plate said, My 3Ds, which stood for Daddy, David, and Douglas.
Life seemed good for the Jensens. Neighbors saw a happy couple working on house projects together, enjoying each other's company while their children played nearby.
Reality, however, was less picture perfect. Captain Olis says police were well aware the Jensen's had been dealing with something ugly.
Those harassing calls and X-rated photos showing up seemingly out of nowhere. Outside the home, like on the car or in the garage even.
Jamboys learned the harassment didn't stop there. Julie wrote in her log, because she kept a log of all of this, new tactic, emails.
With photos? Yeah, emails with penis photos on them. She must have been terrified.
She was terrified. Angelina Gabrielle, an assistant DA at the time, also worked the case.
And she was very embarrassed and humiliated that this kept happening. Julie had made a report that the outdoor furniture had been rearranged? Yes, and she called the police if she saw a strange car across the street.
Julie contacted the police dozens of times over the seven years she lived in Pleasant Prairie. But the department had limited resources, and as time marched on, catching the person harassing Julie fell to the bottom of their pile.
The department's officers were having a really hard time pinpointing who this could be. That'd be accurate, yes.
At one point, police suggested the Jensens hire a private investigator. Julie and Mark met with P.I.
Dave Ellis, a former police officer. She was very, very concerned.
She was scared. During that meeting, Julie revealed a secret that got the PI's attention, something she'd already shared with the police and her husband.
Years earlier, she'd had a fling with a co-worker named Perry Tarika. She suspected he might be behind all this.
That's a difficult thing to share, especially right in front of your husband. Yeah, she seemed remorseful and embarrassed.

Julie told the P.I. that it happened when she had Perry over for dinner one night while Mark was away.

Did she express if they had any other intimate encounters after that?

No, she just had a lot of guilt and just said, you know, this is just, can't happen again.

The police had already looked into Perry and discovered he'd moved to North Carolina, so they doubted he was behind the harassment. But the Jensens weren't so sure.
They suspected he would come to Chicago at the end of the week, drive up to Kenosha, do his deed with the pictures, and then go back. Eventually, the pictures started showing up not only around their house, but also outside Mark's office, slipped under the windshield wiper of his car.
There were pictures of a man and a woman. The woman was performing oral sex on the man.
Could you see any faces? No. The Jensen's hired the PI to do surveillance outside Mark's office.
They said the X-rated photos usually showed up there on a Friday. So this is the location I parked when I did the surveillance.
Did you think you were going to see someone put things on his car? I thought there was a good chance because they had narrowed it down to a Friday, narrowed it down to between noon and five. For several hours, he watched and waited.
No one came? No one came. The PI planned to try again the following Friday, but then Julie called him.
Mark and Julie had said that they had both decided that they were going to terminate the surveillance. Two years later, he learned Julie was dead.
I was shocked because it started out as a harassment case. The DA was still trying to figure out how Julie died.
He'd been on the case about a month when her blood tests came back. Normally at autopsy, you test for things like barbiturates, heroin.
The tech screen came back negative. Nothing.
This is a mystery. It really was.
Meanwhile, investigators were studying that home computer they'd taken from the Jensen's. It was about to send the case in a whole new direction.
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Every case is different. Results vary.
Critisy of Roger Kiernos, Knight Law Group, LLP. Hey, this is Will Arnett, host of Smartless.
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Download it today. A few months after Julie's mysterious death, DA Jamboys finally got a break.
It came from the Jensen's home computer. Someone had been searching drug interactions and poisons, in particular, ethylene glycol, the main ingredient in antifreeze.
Now you have something to work with, potentially. So we took this new information to our medical examiner and we said, what can you do to test for ethylene glycol? Was it too late? No.
So they tested Julie's blood again. And what the forensic toxicologist found this time changed everything.
Traces of ethylene glycol. The DA now knew Julie had been poisoned, but didn't know how.
I spent hours and hours and hours learning about ethylene glycol poisoning. And what I learned is that most ethylene glycol deaths are suicides.
Suicide? Had Julie Jensen killed herself? After researching her past, he could see how it was possible. We had Julie Jensen going to see a family therapist in 1990 and 1991 in which she told him of a family history of depression and in which she complained of being depressed, and he prescribed a Paxil to her.
Julie had been diagnosed with postpartum depression after her first son was born. And when Jamboy's dug a little deeper, he discovered that wasn't the only time Julie had been prescribed an antidepressant.
We had her going to see the doctor and telling him on December 1st that she was miserable, and she was very, very unhappy and depressed. And he prescribed Paxil to her just a few days before she died.
Did she ever mention suicide to the doctor? No. In fact, the doctor had asked her about suicide, and she said, I would never commit suicide.
He knew it wasn't uncommon for someone to say they wouldn't do it and later go through with it. But he thought too many things weren't adding up.
For one, police didn't see any ethylene glycol in Julie's house. In the typical suicide by ethylene glycol, the person is found dead in a room with an empty glass.
And there wasn't much of the poison in her system. Suicide deaths by ethylene glycol are always large quantities.
People don't slowly dose themselves. They do it all at once with a large ingestion that they believe will

kill them immediately. So this didn't look like suicide.
The toxicology report suggested Julie

had been ingesting the poison over a few days. The more you looked at all the circumstances,

the more you believed this looks like murder. It looked like murder, yes.
The police once again

looked into Perry Tarika, the man Julie had the brief affair with. They checked his phone records

Thank you. This looks like murder.
It looked like murder, yes. The police once again looked into Perry Tarika, the man Julie had the brief affair with.
They checked his phone records, spoke to his boss. Your department did do a whole investigation into Perry.
They cleared him. And of course, detectives took a close look at Julie's husband.
Turns out they'd uncovered other evidence on that home computer. Mark had had an affair of his own.
There was evidence, clear evidence of a romantic relationship with Kelly Labonte. An assistant who worked for the same brokerage firm as Mark.
Police discovered racy emails between the married lovers. Kelly Labonte worked in the St.
Louis office. He worked in the Kenosha office, but he went to St.
Louis on a couple of occasions, and he commenced having a sexual relationship with her.

And he was doing that in the months preceding Julie's death.

And according to Mark's co-workers, it was no secret.

Stacey Bauer, another assistant at the brokerage firm, met Mark and Kelly when they briefly worked together setting up a new branch office.

Did you know that Mark was married?

Yes.

Which piqued her interest, since Mark and Kelly were spending all of their time in an office away from everyone else. What are people saying? What's the gossip? I think they're having an affair, something's going on, and, you know, she just got married.
She just came home from her honeymoon, and look at those two, and isn't this weird? The more police looked into the case, the more they were looking at Mark. Then, one day, about four months into the investigation, Mark popped into the station with his nine-year-old son, David, looking for any updates.
The police saw an opportunity. This is a significant moment here in this investigation.
A moment that I didn't know was taking place as it was taking place. The lead detective took a chance and asked Mark to follow him into an interrogation room while another officer watched his son.
The detective had a long list of questions for Mark, like what happened the morning Julie died. She was bad off enough to where you would have called the rescue squad, but she didn't want you to.
She didn't want me to. Well, right, I should have.
I knew in hindsight. I know that.
So you didn't do anything to aid her death, but you didn't do anything to stop her from dying. I really didn't.
I mean, I just watched it happen. That admission clearly caught the detective's attention.
He then asked Mark to explain something that had been puzzling police. The autopsy photos showed Julie's nose pushed to the side.
He offered to show them to Mark. You can see here, look at the nose.
How it's bent, like it was pushed into the pillow. Mark looked at the pictures but gave no explanation.
The detective grew frustrated.

He thought Mark was hiding something, but he had a plan to rattle him.

He was about to show him a letter from Julie, her voice from the grave.

It's one of those moments where he's thinking, oh my God, I'm done.

In the interview room, the lead detective investigating Julie Jensen's murder was starting to lose his patience. Julie's husband, Mark, seemed to dodge every question.
The detective pressed him about his relationship with Kelly Labonte. And there it was.
The detective knew that was a lie. And it was a doozy.
Not only were Mark and Kelly a lot more than friends, police discovered Kelly had left her husband and moved into Mark's house just weeks after Julie died. By this time, Mark Jensen, by the way, had paid $12,000 to Kelly Labonte to move from St.
Louis to Kenosha, Wisconsin.

And not only that, investigators were stunned to learn just days after Julie's death,

Mark had thrown out all of his wife's things,

perhaps to make room for his girlfriend, they thought.

Just sitting out with the garbage, all of her clothes,

there was like 10 to 15 garbage bags tossing her life out.

This is sounding like the oldest motive in the book,

killing your wife so you can be with the other woman.

Yes.

Mark Jensen continued to downplay his relationship with Kelly.

And as the interview dragged on, the detective tried a new approach.

Mark wouldn't confess.

And what happened next took the buttoned-up stockbroker by surprise.

The detective pulled out a letter written by none other than Julie herself, addressed to the Pleasant Prairie Police Department. The detective learned Julie wrote the letter after she found a post-it note written by Mark with a shopping list of things that alarmed her.
This list was in my husband's business daily planner, not meant for me to see.

I don't know what it means, but if anything happens to me, he would be my first suspect.

Julie even sent a photo of the list.

On it, drug supply, razor blades, syringe.

She wrote,

I pray I'm wrong and nothing happens, but I'm suspicious of Mark's suspicious behaviors and fear for my early demise. She wrote, Prosecutor Angelina Gabriel learned Julie had given the letter to a neighbor shortly to the police.
She predicted her own death.

She did.

She did.

Read this.

And now the letter was in the hands of the man

Julie named as her likely killer.

The detective wanted Mark to read it alone.

Just stay here.

Let me go.

Let me go.

Grab a soda.

As the minutes ticked by, Mark appeared frozen.

Only his eyes moved as he read and reread Julie's words.

It's one of those moments where he's thinking, oh my God, I'm done. Mark is an arrogant man, and he did not expect Julie to have the wherewithal to come to these conclusions and put them in writing and give them to someone else for safekeeping.
When the detective came back, again, he pushed Mark to confess. The detective kept at it.
You had to do something to cause her death, Mark. You're the only person that was there, and you're the only person that could have done anything.
Be honest with me. Be straight with me, Mark.
Be a man. Tell me what happened here.
Mark insisted the detective had it all wrong, but the detective wouldn't let up. He accused Mark of being the one behind the X-rated photos that had tormented Julie for years,

guessing he planted them in retaliation for her brief affair.

Mark claimed he wasn't the one who planted the photos in the first place,

but he said he held on to them and later put a few X-rated photos around the house to upset Julie. It was something, but of course humiliating and harassing his wife with pornography was not an admission of murder.

After four hours, the police had no choice but to let Mark walk out of the station.

And even though the district attorney thought Mark was the killer, he didn't think he could prove it.

You had a lot of things working against you in this case. We did.
Everybody was telling me I didn't have enough evidence to convict Mark Jensen.

The DA knew from the toxicology report that Julie had been poisoned with ethylene glycol. But he had no evidence that Mark gave it to her.
And he couldn't say for sure Mark was the one searching it on the home computer. And as for Julie's letter pointing the finger at him? You'd think once you hear a letter like this that it's game over.
That, well, I guess we have our killer. There were problems with the letter.
It wasn't that easy, was it? In terms of its admissibility. The issue for the prosecution was that defendants have the right to cross-examine anyone who provides evidence against them.
In this case, Julie couldn't be questioned because she was dead. But the prosecutor didn't think that should apply in this case.
Mark had forfeited his right to cross-examine the witness because he was responsible for being gone. So I had to convince the judge that this letter was admissible, and it was a huge fight.
A fight that would take years. All the while, the prosecutor watched Mark move on, building a successful construction company and a new life with his girlfriend.
Then he saw an announcement in his local paper. I read in the newspaper that Mark Jensen was marrying Kelly Labonte.
And I thought, she's victim number two. When he gets tired of this toy, he's going to toss her in the trash heap like he did with Julie.
Even though the prosecutor didn't think he had an airtight case, he got an arrest warrant and charged Mark with first-degree murder. The police headed over to the Jensen house.
Jamboyes figured Mark had no idea what was coming. What was the look on Mark's face when he was arrested? I think he was very shocked.
Mark always thought of himself as just the smartest guy in every room. He always thought he could talk himself out of everything.
It was a short victory for the prosecutor. Mark didn't stay behind bars for long.
He posted a half-million-dollar cash bond. From there, the case stalled while the prosecutor fought to have Julie's letter admitted at trial.
Mark's life once again seemed to go on as if nothing had happened. Getting married, working, having another child,

raising the two children whose mother he murdered.

This must have been just eating away at you that he's out there free.

It's stuck in our crop.

But things were about to change.

A surprise witness appeared out of nowhere and dropped a bombshell.

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Results vary. Criticism of Roger Kiernos, Knight Law Group, LLP.
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The years ticked by. Mark Jensen remained out on bail with no trial in sight.
Bob Jambois left the DA's office in 2005 to work for the Wisconsin Department of Transportation. But he wasn't about to let go of Julie Jensen's case.
It had become an obsession. He continued as a special prosecutor.
I was laid awake at night thinking of ways I was going to prosecute Mark Jensen, assemble the evidence to hold him accountable for what he'd done to Julie. It wasn't until eight years after Julie's murder that the case finally broke wide open.
Jamboys presented a new witness at a pretrial hearing. Ed Klug, a co-worker of Mark's, said the two had been at a business conference about three weeks before Julie's death.
He and Mark were drinking at the hotel bar. The more he drank, the more he started to talk.
And I had gone through some marital issues. So, and I think he kind of brought up how he hated his wife.
How deep did this conversation go? Well, basically it went very deep because he talked about how he could kill her. At first I thought he was just all, you know, you joke, I'm going to kill my wife.
But it's like the more he talked and the more details of telling him about the websites you could go to, the poisons. And did you think about going to the police with this to warn or warn Julie? No, at that time I didn't because I didn't know how serious he was.
Still, Ed told this story to several other people, including office assistant Stacy Bauer. He said as the conversation went on with Mark, he said he really started to feel weird and that Mark really did want his wife dead.
What did you think about that? I'm like, weird? What an odd guy. And then I kind of forgot about it.
But all that changed a month later. Ed came up to me again and he said, um, Julie Jensen is dead.
And I said, oh my God. I mean...
He killed her. After hearing Ed's story, the judge took immediate action.
He quadrupled Mark Jensen's bond. Mark couldn't make bond and was sent straight to jail.
The judge also did something Jamboys had been arguing for for years. Judge Schrader ruled that the letter was admissible.
It was coming in. That's a huge win.
It was a huge win. But would it be enough to convince a jury?

On January 8, 2008, nine years after Julie was murdered, Mark Jensen went on trial. This case was front page every day.
In his opening statement, Jamboyes read Julie's letter, her once private thoughts pointing the finger at her husband. If anything happens to me, he would be my first suspect.

Jamboy's painted a picture of a terrified woman who was not suicidal, as the defense would claim, but desperate for help, even reaching out to a Pleasant Prairie police officer days before her death. And he told Julie, there's really no basis for us to suspect that your husband is trying to kill you.
And really, if you're concerned about that, you should go to a woman's shelter, you should take your children and leave. But Julie didn't take that advice.
Jambois says she was afraid of Mark and worried that if she fled, he would take her boys. She was prepared to put her own life at risk rather than abandon her two boys.
The prosecutor showed the jury numerous searches for poisons on the Jensen's home computer. But more importantly, he also pointed to online activity the very morning Julie died.
We saw these searches for ethylene glycol poisoning at 9.40 in the morning on December 3rd, 1998. These two searches for ethylene glycol.
Jamboise argued that it had to have been Mark doing the searches, not Julie. Remember, Mark himself told police Julie couldn't get out of bed that morning.
She wasn't looking good. She's got no water control.
If you're in bed and you can't speak and you can't move, you can't be looking up ethylene glycol on the computer. And by the way, those two searches were then double deleted.
And that was one of the linchpins. That was one of the best pieces of evidence we had.
Absolutely. To tell the jury how Mark poisoned his wife, the prosecutor called a controversial witness, a convicted con man named Aaron Dillard, who shared a cell block with Mark Jensen in the county jail.
Jamboise learned about the con man after Dillard wrote a letter to his lawyer claiming Mark not only admitted that he killed his wife,

he described how he did it. This letter clearly reflected evidence, information,

that could only have come from the person that murdered Julie Jensen.

Gretchen Rosenki was Aaron Dillard's lawyer. If Aaron Dillard is telling the truth,

he's providing a window into Julie Jensen's final moments of her life. What exactly did he tell you he heard from Mark? Mark told him that she didn't die just after ingesting the antipreeze.
So after the kids were at school, he pushed her head into the pillow until she suffocated. Jamboys had suspected asphyxia from the beginning because of the unnatural position of Julie's arm tucked under her body and the way her nose was bent to the side.
When we rolled her back, she was like, her face was squished off like this. So the con man's story made sense.
Jamboys asked Diller to tell the jury what Mark said happened step by step. He gave her juice to drink, and that was when he told me at that point it was mixed with the antifreeze.
Diller testified that Jensen told him he'd given Julie small doses of antifreeze mixed into her juice over a few days. On the morning Julie died, his boys saw how sick she was and wanted their dad to call for help.
He told them that if she wasn't better by the time they got home from school,

that he would call the ambulance.

The clock was now ticking.

Hours went by.

Dillard says Jensen told him he came back to check on Julie and she was still breathing.

The boys would be home soon.

So according to Dillard, Jensen said he took matters into his own hands.

That's when he said he rolled her over and just sat on her back and pushed on her neck into the pillow. He wanted to be with the other woman, and he had a lot of money.
And he didn't want to share any of it with Julie. He didn't want to share the children.
But Mark's attorney, Craig Albee, told the jury the prosecution had taken the facts and come to the wrong conclusion. Finally, after nine long years, Mark Jensen can clear his name.

The defense argued that Mark didn't kill Julie so he could be with the other woman.

Instead, they said Julie killed herself so she could get revenge by framing Mark for her murder.

Her depression and her despair and her anger and her delusional thinking caused her to point the finger at Mark.

Dr. Richard Borman, Julie's primary care physician, testified for the defense that she came to see him just two days before her death.
You know, she seemed to be depressed and distraught and almost frantic, actually.

Dr. Borman said Julie was concerned about her family's history with mental illness, especially her mother's struggle with alcoholism and depression.
She was very concerned about going down the same path as her mother and was afraid of that, didn't want to be labeled crazy. And as for Aaron Dillard, on cross-examination, the defense accused the con man of making up his story to help himself.
The trial dragged on for seven weeks, one of the longest criminal trials in Wisconsin history. Jamboyes was hoping for a quick verdict, but three days passed and the jury was still out.
But then came word. We, the jury, find the defendant, Mark D.
Jensen, guilty of intentional homicide of the first degree. The judge gave Mark the harshest possible sentence, life without the possibility of parole.
But this case was far from over. After years of appeals, a federal judge made a decision that just might allow Mark Jensen to walk free.
At a press conference after Mark Jensen's guilty verdict, Bob Jamboyes described him as one of the worst criminals he'd ever prosecuted. I cannot recall a more cold-blooded, calculated, brutal offense than this one.
His co-counsel, Angelina Gabrielle, got emotional. She, like Julie, had two young sons.
I think that this was more about preserving Julie's memory for her boys. Because not only did Mark kill her, but he killed the memory that these boys had of her.
And the guilty verdict stood for years. Mark remained behind bars while his legal team appealed.
Then, 13 years after his conviction, a Supreme Court decision changing admissibility rules opened the door for Mark Jensen. An appellate court vacated his conviction, saying Julie's letter should not have been admitted.
The court granted Mark a new trial, and in January of 2023, he faced 12 new jurors. But with one big difference, this time they would not hear about the letter.
Did you think that that would hurt you? I thought that. I thought it would hurt us.
Jamboys came back once again as a special prosecutor. This time he tried the case with Deputy DA Carly McNeil.
Where were you in your life when Julie Jensen died? I was in eighth grade. I had no idea that it even happened.
Much of the evidence was the same. Ed Klug told the jury about the conversation he had with Mark three weeks before Julie died.
He told me he was going to kill his wife. Jailhouse snitch Aaron Dillard testified about Mark confessing to killing Julie.

He sat on her back and then pressed her face into the pillow.

And another former inmate who shared a cell block with Mark also told the jury a damning story.

Back in 2007, David Thompson was in the Kenosha County Jail for bank robbery when he met Mark.

We came kind of close. You know, we would talk every day, drink coffee together every morning.

Mark eventually shared with David that he wanted to stop his co-worker, Ed Klug, from testifying against him. What did he want to happen to Ed? He wanted him kidnapped, you know, to prevent him from coming to trial.
And I told him, I might be able to make that happen for you. Wow.
And how did Mark respond to that? Oh, he was ecstatic. He was happy to hear that.
Thompson says he had no intention of going through with it. It was never going to happen.
It was just a scheme to trick Mark out of some money. He told Mark for $1,000 he could have someone kidnap Ed and hold him until after the trial.
Did Mark ever talk about having Ed killed, or was it just kidnapping? Whatever needed to be done, he wanted done. Jamboys played a jailhouse recording of a call from Mark to his wife Kelly asking her for money, but he didn't tell her what it was for.
How much? Oh, I'd be like $500. Okay.
Maybe twice, and that would be it. $1,000, just as Thompson had described.
And there was something else. The answer to a big question.
A computer forensic specialist uncovered zip drives that finally revealed who was behind the pornographic photos that frightened and humiliated Julie for years. The photos were emailed from a sender with the name Turtle.
Did Turtle have any connection to Mark Jensen? Turtle was M. Jensen at execpc.com.
He had simply changed the name in the from, you know, you just type in a new name. Right.
This is what connected this trove of pornographic photos on Mark Jensen's work computer to these penis photos that are being left around Julie Jensen's home. Mark had a new defense team.
Again, they argued that Julie was depressed and killed herself. But without Julie's letter, they didn't claim she tried to frame Mark.
And they also had a new witness, Julie and Mark's son, David, now 33 years old. Did you think that that would resonate with the jury, that Julie's own son is standing by his dad? You know, that was something that we definitely had concerns about because we didn't know what he was going to say.
You wanted your dad to take your mom to the hospital, right? The discussion was that if she wasn't feeling better when we got home, we'd take her to the hospital. In the end, the prosecutors thought his testimony helped their case.
His father promised him if he came home from school on December 3rd and his mom wasn't better, they would take her to the hospital, which matched exactly what Aaron Dillard said. The reason for the suffocation is because Julie wasn't dead yet and David was coming home from school.
The verdict was swift. The jury took less than seven hours to find Mark Jensen guilty of first-degree murder.
He was sentenced again to life without parole. For Bob Jamboyes, the sentencing was the end of a 25-year quest.
He finally had justice for Julie. How did you feel when you looked at him in court the second time? I felt like putting my gun away.
I got that son of a bitch. And every time that I have a nice steak dinner with a good glass of wine, I'm going to enjoy it all that much more knowing Mark Jensen's getting down a bologna sandwich and a glass of water because that guy's going to die in prison.
That's all for this edition of Dateline. We'll see you again Friday at 9, 8 Central.
And of course, I'll see you each weeknight for NBC Nightly News. I'm Lester Holt.
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