There were months of legal wrangling but eventually investigators were dealt a crushing blow. In 2002, the letter was ruled inadmissible. According to U.S. law, the accused always has the right to face his accuser.
"He can't confront her because he killed her," said an outraged Jambois.
Julie Jensen's four brothers were devastated. "We should fight to get the letter admitted. Because that was Julie's voice," said Paul Griffin, a brother.
In 2007, after years of legal disputes which made their way to the Wisconsin Supreme Court, Julie Jensen's letter was finally ruled admissible and a trial date was set.
Mark Jensen was accused of murder in the first degree, and nine years after his wife's death he was the focus of a high-profile trial shown live on cable television and the Internet.
Attorney General Bob Jambois argued that the man poisoned his wife with anti-freeze and then suffocated her so he could start a new life with his mistress. Kelly LaBonte moved into the Jensen household shortly after Julie Jensen's death, and she and Mark Jensen were married in 2002.
The suffocation argument was a shift in the case that came after Aaron Dillard, a jailhouse informant with an extensive criminal record, came forward. Mark Jensen and Dillard were housed together in a Wisconsin jail, and Dillard said the suspect told him that he had fed his wife juice mixed with anti-freeze but that "[Julie] wouldn't die fast enough." Dillard testified that the suspect told him his sons saw their mother having difficulty breathing and "wanted to take her to the hospital. He told me he got scared. And that's when he rolled her over and sat on her back, pushed her face into the pillow."
In his exclusive interview with "20/20" Dillard said Mark told him a different story initially. Mark said "that she [Julie] poisoned herself with antifreeze and she tried to commit suicide, that basically her whole family was crazy, and she followed the same footsteps." But then, Dillard said, "it started spilling out" after Dillard made a comment about how "all of us have some problem in our life."
"He [Mark] was teary-eyed talkin' about his kids. And that's when I ... brought in the point of we all did what we did to get here. And then he ... that's when he came out with and started telling me more about what he did."
According to Dillard, Mark's demeanor during his purported jailhouse confession was unemotional. "He didn't show any sorrow about his wife been [sic] dead. He didn't. About her passing away. About any of it."
At the trial, defense Attorney Craig Albee quickly attacked Dillard's testimony, and got him to admit he was a con-man on the stand. Albee said simply to the jury, "You heard Aaron Dillard is a liar. You cannot believe him beyond a reasonable doubt."
Witness after witness came forward to talk about Julie Jensen's character and when it was time for Ted Wojt to take the stand he told the jury that Jensen believed her husband was trying to kill her. Ted testified that she had seen him "on poison sites" on the Internet. He believed she thought her husband was "trying to make me look crazy, to take my kids." Julie Jensen took her suspicions to the police before she died but, without proof, her husband was not questioned.
Julie Jensen had filed for divorce years earlier but Julie's brother Paul testified that Mark told Julie she would never see their sons again if she went through with it.