KENOSHA COUNTY, Wis. — Mark Jensen, 66, is asking a Kenosha County judge for a new trial in the 1998 death of his wife, Julie Jensen, whose poisoning prosecutors have attributed to antifreeze. Jensen is serving a life sentence after a jury convicted him in a 2023 retrial. His attorneys, led by Madison lawyer Joseph A. Bugni, filed a post-conviction motion raising five claims and asking the court to hold an evidentiary hearing. No hearing had been scheduled as of Sept. 22, 2026. The motion argues that Jensen’s trial attorneys failed to adequately investigate a late change in testimony from a state computer expert. According to the filing, the expert changed the time zone used to interpret internet-search records, making it appear Jensen was at home when searches for ethylene glycol — the toxic chemical prosecutors said killed Julie Jensen — were conducted. Jensen’s attorneys also challenge the handling of a computer disk introduced late in the case. They say the disk may contain information indicating that Julie Jensen used the computer and created a harassment campaign that prosecutors had linked to her husband. The motion further alleges that prosecutors withheld potentially favorable files from the disk, which the defense characterizes as a possible violation of the constitutional requirement to disclose exculpatory evidence. Another claim concerns nicotine-related evidence. The filing says defense lawyers did not sufficiently challenge evidence connecting Jensen to a prescription for nicotine that prosecutors tied to an online search for poison. The defense points to phone and medical records that it says suggest Julie Jensen made the calls involved in obtaining the prescription. The final claim is that the combined effect of the alleged errors deprived Jensen of a fair trial, even if individual issues do not independently warrant a new proceeding. The claims remain allegations in a post-conviction filing, and the court has not ruled on Jensen’s request. The case has continued for more than two decades. Jensen was first convicted in 2008, but a federal appeals court later overturned that conviction, ruling that a letter Julie Jensen wrote accusing her husband of planning to kill her should not have been admitted because its use violated Jensen’s constitutional right to confront witnesses. The Wisconsin Supreme Court upheld that ruling in 2021, clearing the way for the 2023 retrial. The new motion places the reliability and disclosure of digital evidence at the center of the latest phase of a case that has already included two trials and federal habeas proceedings.