Bob Jambois, the former Kenosha County District Attorney who has been involved in the prosecution of the case for more than two decades, described the letter as Julie’s final wishes. He believed it was her request documented in the letter. In 2008, Bob Jambois shared this perspective with “20/20.” In 2011, an appellate court reversed the conviction, ruling that the letter should not have been used in the trial as it violated Mark Jensen’s Sixth Amendment rights to confront the witnesses against him.
In January 2023, prosecutors retried Mark Jensen without the letter, focusing on other evidence such as internet searches on his computer that they claimed demonstrated his guilt. After a day of deliberations, a jury convicted him on Feb. 1. “20/20” will revisit the case in an upcoming episode airing on Feb. 10 at 9 p.m. ET, with interviews featuring Julie Jensen’s friends and family, prosecutors, and key witnesses who testified against Mark Jensen.
Bob Jambois noted from the start of the investigation that it would be a challenging case due to the absence of immediate indications of foul play. Despite this, he felt something was amiss, especially in Mark Jensen’s behavior, which he perceived as lacking remorse or grief following Julie Jensen’s death. Friends of Julie Jensen told “20/20” they also had suspicions about Mark Jensen’s conduct. Ruth Vorwald recalled an instance where Mark Jensen appeared nonchalant at his wife’s wake, raising concerns about his demeanor.
Moreover, Julie Jensen’s neighbors, Ted and Margaret Wojt, revealed that she had given them an envelope before her death instructing them to give it to the police in case of any incidents. After Julie Jensen passed away, the Wojts handed over the sealed envelope to the authorities. Inside was a letter penned by Julie Jensen, along with a photo of a shopping list containing a syringe and chemicals. In the letter, Julie expressed concerns about Mark Jensen’s behavior and her fear of potential harm, citing him as the primary suspect if anything happened to her. She adamantly stated she would never harm herself due to her children being her top priority.
The letter also mentioned a past affair of Julie Jensen’s, which she believed fueled hostility from her husband. Mark Jensen was later revealed to have been involved in an affair with a colleague from his brokerage firm before his wife’s death and subsequently married her. Despite arguments from Mark Jensen’s defense claiming Julie Jensen’s death was a suicide staged to frame him for murder, her brother, Paul Griffin, disputed this narrative, asserting his belief in seeking justice for his sister.
Larry Griffin, brother of the late Julie Jensen, vehemently denied the assertion that his sister harbored vengeful tendencies. Holding a photograph of Julie Jensen, he expressed disbelief at the notion, stating, “That’s the craziest thing I’ve ever imagined. I don’t know how anyone could believe that, anyone.”
As the jury deliberated in Mark Jensen’s trial at Kenosha County Courthouse on Jan. 31, 2023, prosecutors contended that the evidence pointed towards Mark Jensen having both the motive and means to end his wife’s life. Witnesses presented by the prosecution during the trials testified to inculpating statements made by Mark Jensen.
Ed Klug, a former colleague of Mark Jensen, recounted how Mark had expressed disdain for his wife and referenced poisons and websites related to spousal homicide during a work conference in the fall of 1998. Klug admitted that he refrained from reporting these statements to the authorities out of fear of potential retaliation from Mark Jensen.
During a separate testimony, David Thompson, an inmate who shared a cell block with Mark Jensen in 2007, detailed Jensen’s frustration towards Klug potentially testifying against him. Thompson stated that Jensen expressed a desire to eliminate Klug, leading Thompson to concoct a fabricated scheme to abduct Klug for financial gain. However, no actions were taken, and no charges were filed as a result.
Following a nearly month-long trial, the jury swiftly reached a guilty verdict against Mark Jensen after just one day of deliberation. The outcome brought a sense of closure to Julie Jensen’s loved ones, with Larry Griffin expressing relief at the verdict. Griffin acknowledged his apprehension prior to the trial’s conclusion, stating, “I worried that he might not be found guilty without the letter. It was really unknown as to what was going to happen.”
Mark Jensen, upon hearing the verdict, announced his intention to appeal the decision. Prosecutor Robert Jambois dismissed Jensen’s plans for another trial, expressing confidence in the existing conviction and declaring, “If he does, I’ll be back and will try this son of a b—- again.”
Sentencing for Mark Jensen is scheduled for April 14, with the convicted individual maintaining his stance on challenging the verdict through an appeal process. The unfolding events surrounding the case of the 1998 antifreeze poisoning highlight the complexities and intricacies of the judicial system, leaving lingering questions and uncertainties in the aftermath of the trial.
