The neighbors walked into the Pleasant Prairie Police Station the day after Julie Jensen was found unconscious in her bed. It was December 1998, just days before Christmas, and they carried a sealed envelope she had given them weeks earlier with specific instructions. Open this only if something happens to me. Inside was a handwritten letter dated November 21st, 1998, twelve days before Julie passed.

The letter named her husband Mark as her suspected killer. She described his internet searches about poisons, his strange behavior, his coldness, his threats. She wrote that if she turned up sick and helpless, Mark would be responsible. Julie Jensen had seen her own fate coming.

She had documented everything she could, and she had left a message from beyond the grave, pointing directly at the man who slept beside her every night. The initial autopsy had been inconclusive. No obvious trauma. No clear cause.

Just a healthy forty-year-old mother of two who went to bed and never woke up. Her husband told paramedics she had been feeling under the weather. Nothing serious. It should have ended there.

An unexplained loss, a grieving widower, a case that slowly goes cold. But Julie Jensen refused to let that happen. She had written her own testimony before her killer could silence her. That letter would haunt Mark Jensen for the next two decades.

Julie Griffin grew up in Wisconsin and met Mark Jensen in 1981. They were both college students at the time. She was working at a Sears department store in Oshkosh. He was studying to be a stockbroker.

They fell for each other quickly and married not long after. The couple settled in Pleasant Prairie, a small town on the shores of Lake Michigan, about forty miles south of Milwaukee. It was the kind of place where people knew their neighbors, where kids played in quiet streets, where nothing particularly dramatic ever happened. A safe, quiet community.

Mark became a branch manager for a financial firm based in St. Louis. He was good at his job, ambitious, driven, focused, the kind of employee who climbed the ladder quickly, the kind of person who kept meticulous records, planned everything in advance, and did not tolerate mistakes. Julie stayed home to raise their two sons, David and Douglas.

By 1998, the boys were eight and three years old. From the outside, they looked like a perfectly normal family. Nice house, two kids, stable income. Friends and neighbors saw a couple that seemed content.

They attended community events. They went to church. Mark was charming in public, always ready with a smile and a handshake. Julie was devoted to her children, the kind of mother who volunteered at school functions and knew all the other parents by name.

But behind closed doors, the marriage was fractured. Cracks that had started small were widening into something that could not be repaired. In the early 1990s, Julie had a brief affair with a co-worker. It was short-lived, and she confessed it to Mark.

She thought they could move past it. She was wrong. Mark Jensen never forgave her. After the affair came to light, someone began harassing Julie.

Pornographic photos were left around the house. They appeared on the Jensen’s vehicles. Hang-up phone calls came at all hours. Julie kept a detailed log of every incident.

She never identified the perpetrator, but she had her suspicions. The harassment went on for years. By the fall of 1998, Julie was seeing a psychotherapist for depression. Just two days before her passing, she visited her doctor for an antidepressant prescription.

But Julie Jensen was not suicidal. That is what her family insisted for decades, and they knew her better than anyone. She had two young boys who needed her. She would never leave them.

She loved them too much. And she knew with terrible certainty that her husband was planning something. The letter Julie gave to her neighbors was written on November 21st, 1998. She sealed it in an envelope and gave them clear instructions.

If anything happens to me, give this to the police. Twelve days later, Julie was found lifeless in her bed. When investigators opened the envelope, they found not just a letter but a photograph. Julie had taken a picture of a handwritten list she had found in her husband’s business planner.

A list that was not meant for her to see. The items on that list were chilling: own drug supply, bag hands, syringe. It read like instructions for how to end someone’s life and get away with it. In her letter, Julie laid out her suspicions.

She wrote about her husband’s suspicious behaviors. She described their relationship as having deteriorated to the polite and superficial. And then she wrote the words that would haunt this case for a quarter century. I pray I’m wrong and nothing happens.

But I am suspicious of Mark’s suspicious behaviors and fear for my early demise. She also wrote, I would never take my life because of my kids. They are everything to me. Julie Jensen knew she might be killed.

She documented everything. And then she went back to living in the same house as the man she suspected was planning to end her life. Why did she not leave? Leaving is not always simple when you have two young children, when your husband controls the finances, when you are not entirely sure if your suspicions are paranoia or reality.

Julie stayed. And twelve days later, she was gone. When investigators searched the Jensen family computer, they found something that confirmed Julie’s worst fears. Someone had been searching the internet for information about poisons.

Specifically, they had researched ethylene glycol, the main ingredient in antifreeze. The searches covered how it worked, what symptoms it caused, and how long it took to be fatal. The toxicology results came back weeks after Julie’s passing. Her blood, stomach, and urine all contained ethylene glycol.

She had been poisoned with antifreeze. Antifreeze is a particularly insidious poison. It is sweet-tasting, easy to disguise in a drink. Victims often do not realize they have been poisoned because the initial symptoms mimic the flu.

By the time the victim realizes something is wrong, the damage is often irreversible. Julie had told Mark she was not feeling well in the days before she passed. She thought she was coming down with something. She was actually being poisoned, likely over multiple days.

Small doses that accumulated in her system until her body could not fight anymore. Investigators also found evidence that Mark had been having an affair. Her name was Kelly Labonte, and she worked at the same financial firm. The affair had started before Julie’s passing.

Within months of Julie’s death, Kelly moved into the Jensen home. Not long after, she and Mark were married. Kelly took over raising David and Douglas, stepping into the role of mother to two boys who had just lost their own. To Julie’s family, the timeline was damning.

Mark had found his wife’s replacement before he had even disposed of his current one. The prosecution’s theory was straightforward. Mark Jensen wanted out of his marriage. He had found someone new.

But divorce would be expensive and messy, especially with two kids involved. Julie might get custody. She might get the house. She might tell everyone what he had been doing to her for years.

So he decided to get rid of her permanently. The internet searches were not curiosity. The list in his planner was not a coincidence. He was planning a murder.

Mark Jensen was not arrested immediately. The case was complicated. The toxicology results took time, weeks of testing before the ethylene glycol was confirmed. Building a murder case around poison is difficult.

You need to prove not just that the poison was present but that someone deliberately administered it. And Mark’s attorneys would later argue that Julie could have ingested the antifreeze herself. Meanwhile, Mark Jensen was moving on with his life. He remarried.

He continued working. He raised his sons with his new wife in the same house where Julie had passed away. To anyone who did not know the circumstances, he was just a widower who had found love again. He attended church.

He showed up at his sons’ school events. But investigators never stopped looking at him. They gathered evidence quietly. They built their case piece by piece.

The internet searches, the co-worker testimony on the timeline of the affair, the letter Julie had left behind. Nearly a decade passed before Mark Jensen stood trial. In 2008, prosecutors finally brought him before a jury in Kenosha County, Wisconsin. The trial was moved to Walworth County because of pre-trial publicity.

Everyone in Kenosha had heard about the letter from the grave. The letter was the centerpiece of the prosecution’s case. Jurors heard Julie’s own words read aloud in court. They saw the photograph of Mark’s handwritten list.

They heard from co-workers who testified that Mark had talked about hating his wife and had discussed poisons in the months before she passed. One co-worker, Ed Klug, testified that during a work conference in the fall of 1998, Mark Jensen spoke openly about despising his wife and mentioned websites about how to end a spouse’s life. Then Klug said he did not go to police at the time because he did not take it seriously. He thought Mark was just venting.

He also feared what Mark might do if he reported him. Looking back, I wish I would have taken him seriously, Klug later said. The defense had a different story entirely. They argued that Julie Jensen had been severely depressed.

They pointed to her mental health struggles, her visits to a therapist, her prescription for antidepressants. They suggested she had taken her own life and used her letter to frame her husband for murder as a final act of revenge. It was a suicide disguised as a homicide, they claimed. Julie wanted to punish Mark, so she ended her own life and made it look like he did it.

The jury did not buy it. Not for a second. On February 21st, 2008, nearly ten years after Julie’s passing, they found Mark Jensen guilty of first-degree intentional homicide. He was sentenced to life in prison without parole.

Your crime is so enormous, so monstrous, so unspeakably cruel that it overcomes all other considerations, the judge said at sentencing. It was a damning condemnation from the bench. Julie’s family felt vindicated. Her brother Larry called the letter a mandate that they had passed on to the people of Wisconsin.

But the case was not over. Mark Jensen appealed his conviction. His argument centered on the letter. Under the Sixth Amendment, defendants have the right to confront witnesses who testify against them.

Mark could not cross-examine Julie. She was gone. Therefore, the letter should not have been admitted as evidence. For years, the appeals worked their way through the courts.

In 2013, a federal judge agreed with Mark and overturned his conviction. The state appealed. In 2015, the US Court of Appeals for the Seventh Circuit upheld that decision. Mark Jensen’s conviction was vacated.

He was released from prison after serving seven years. He walked out the doors a free man. For a while, it looked like he might escape justice permanently. But prosecutors were not finished.

In 2016, they announced they would retry Mark Jensen for his wife’s murder. This time, without the letter. If they could not use Julie’s words, they would prove the case with everything else. The internet searches, the toxicology, the affair, the co-worker testimony.

It was a significant risk. Without Julie’s voice from beyond the grave, without her own words pointing at her husband, why would the jury still convict? The second trial began in January 2023, nearly twenty-five years after Julie’s passing. The prosecution presented much of the same evidence, but without the letter that had been so central to the first trial.

On February 1st, 2023, after just one day of deliberation, the jury found Mark Jensen guilty. Again. Twenty-five years after Julie’s passing, he was finally being held accountable a second time. The evidence was enough without the letter.

The internet searches about poison, the ethylene glycol in her system, the co-worker who heard Mark talk about ending his wife, the affair, the pattern of behavior. On April 14th, 2023, Mark Jensen was sentenced for the second time to life in prison without parole. He is currently incarcerated at Oshkosh Correctional Institution. He plans to appeal again.

His lawyers are already working on the filing. The prosecutor, Bob Jambois, was not worried. He had been working on this case since the late 1990s. He had tried it twice.

He had won twice. If he does, Jambois said after the verdict, I’ll be back and we’ll try this son of a gun again. Julie’s sons, David and Douglas, have grown up now. They were just eight and three when their mother was killed.

For years, they publicly supported their father, even asking the judge at his first sentencing to give him a chance at parole someday. They had been raised by Kelly, the woman their father had been having an affair with. It is impossible to know what they believe now after a second conviction. They have had to live with the knowledge that their father killed their mother.

That is a weight no child should ever have to carry. A burden that will follow them forever. Julie Jensen did something remarkable. She knew she was in danger.

She documented her suspicions. She wrote a letter, sealed it in an envelope, and gave it to neighbors with instructions to hand it to police if anything happened. And then she stayed. Maybe she thought she was wrong.

Maybe she hoped she was paranoid. Maybe she did not know where else to go with two young boys who depended on her. Twelve days later, she was gone. But her letter survived.

It pointed investigators in the right direction from day one. It told them who to look at, what to search for, where to dig. Even when the court said it could not be used, the evidence Julie’s letter led investigators to find was enough to convict her husband twice. She could not testify at trial.

She could not confront the man who poisoned her. But her words reached across the decades anyway. Mark Jensen thought he had gotten away with it. He remarried.

He raised his sons with his new wife. He lived freely for years while the case worked through appeals, thinking he had beaten the system. But Julie’s letter was always there, waiting. Julie Jensen made sure that if her husband killed her, he would not get away with it.

She put it all in writing. She sealed it in an envelope. She trusted her neighbors to deliver it when the time came. She was right about everything.

And her letter made sure the world would know it.