'Dateline NBC' tackles 1998 murder of Julie Jensen, for which husband Mark was convicted twice

Chris Foran, Milwaukee Journal Sentinel
·2 min read

True-crime series "Dateline NBC" takes a dive into the 1998 death of Julie Jensen in Pleasant Prairie, for which her husband Mark Jensen was convicted of first-degree intentional homicide — twice.

The installment, titled "Secrets in Pleasant Prairie," will air on NBC at 9 p.m. Oct. 12.

The log line for the episode, which NBC sent out Tuesday, reads: "The investigation into the poisoning death of Wisconsin mother-of-two Julie Jensen takes a surprising turn when detectives learn that Julie wrote a letter just days before her death pointing to a possible suspect."

Julie Jensen was 40 when she was found dead in the couple's garage in December 1998; she had been poisoned with antifreeze and sleeping pills, then suffocated with a pillow. Attention turned quickly to her husband; in his first trial, the evidence against him included a letter his wife had left with a neighbor as well as voicemails left for a police officer all suggesting that if she was found dead, her husband likely was responsible.

Julie and Mark D. Jensen
Julie and Mark D. Jensen

After he was convicted in 2008 and sentenced to life in prison, Mark Jensen filed a barrage of appeals, challenging the evidence shown to the jury, especially the letter and voicemails, saying allowing it in the trial violated his Sixth Amendment rights to confront his accuser.

In March 2020, following several other rulings in Jensen's favor, a Wisconsin Court of Appeals ordered a new trial in the case and barred use of the "voice from the grave" evidence. The state Supreme Court reaffirmed the decision.

In February 2023, a second jury again found Mark Jensen guilty of first-degree intentional homicide, and again he was sentenced to life in prison.

Mark Jensen, center, talks with his attorneys Mackenzie Renner, left, and Bridget Krause during his trial at the Kenosha County Courthouse on Jan. 11, 2023, in Kenosha. The Wisconsin Supreme Court ruled in 2021 that Jensen deserved a new trial in the 1998 death of his wife Julie Jensen.
Mark Jensen, center, talks with his attorneys Mackenzie Renner, left, and Bridget Krause during his trial at the Kenosha County Courthouse on Jan. 11, 2023, in Kenosha. The Wisconsin Supreme Court ruled in 2021 that Jensen deserved a new trial in the 1998 death of his wife Julie Jensen.

Among the people interviewed for the "Dateline" report on the case by Andrea Canning are, according to NBC, Pleasant Prairie Police Department Captain Barry Ollila, former Kenosha County District Attorney Bob Jambois and private investigator Dave Ellis.

The granddaddy of true-crime series, "Dateline NBC" is in its 32nd season, NBC's longest-running prime-time show ever.

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This article originally appeared on Milwaukee Journal Sentinel: 'Dateline NBC' takes on 1998 Julie Jensen murder in Pleasant Prairie