
(PEOPLE)
A child-killer has been sentenced to multiple decades in the Illinois prison system.
According to news reporters present at a sentencing hearing in Illinois’ Tazewell County Court on September 17, 2021, 35-year-old Lesli Ann Jett was essentially emotionless during the five hour court proceeding. Her only reaction to speak of was an audible but unintelligible yelp while the prosecution, led by Assistant State’s Attorneys Mara Mishler and Sarah Schryer, discussed the 260 injuries found during Tate’s autopsy. As Lesli pulled off her face mask and wiped tears from her face, Judge Paul Gilfillan chided her about refraining from outbursts and reminded her that she would be allowed to address the court before receiving her sentence.
After a two-week trial, Lesli was convicted in July — by a jury that deliberated for just 80 minutes — of first-degree murder with intent to kill or cause great bodily harm to a child under 12; first-degree murder with the knowledge that her acts bore the strong probability of death or great harm; and aggravated battery to a child under 12. These charges stemmed from the death of 4-year-old Tate Thurman, the son of Lesli’s live-in boyfriend, Jeremy Thurman, who was at work on the morning of February 18, 2020 when Tate was critically injured while alone in Lesli’s care. Tate’s 7-year-old brother had already boarded the school bus and Lesli’s 2-year-old son was still sleeping when Lesli made a panicked 911 call, telling the dispatcher that Tate was unresponsive. She later told police Tate had slipped in a puddle of water and fallen on the kitchen floor.

(HOIABC)
Even after two attempted life-saving surgeries, Tate never regained consciousness. On February 20, 2020, he was removed from life support and succumbed to his injuries.
Lesli was arrested and held in Tazewell County Jail on a $3 million bond until her trial in July of this year. After her conviction, I covered Tate’s story in episode 71 of Suffer the Little Children Podcast.
At the beginning of Lesli’s sentencing hearing on September 17, the defense requested a new trial, which Judge Gilfillan quickly denied.
Wearing a black and white striped jail jumpsuit, Lesli sat stoically at the defense table while the prosecution asserted, as they did during her trial, that Lesli grew more and more frustrated and resentful about being “forced” to care for Jeremy’s two sons, especially Tate, who she claimed was inconsistent with potty training and had frequent accidents. The prosecuting attorneys relentlessly presented evidence during the hearing, including Lesli’s texts to friends, as well as testimony from cell phone and drug experts, about a two-year amphetamine addiction that caused Lesli to become increasingly hateful and cold-hearted.

(Phil Luciano/Journal-Star)
Presenting over 60 pages of text messages, Mara Mishler described Lesli’s worsening behavior as she bought, sold, and used Adderall and other prescription amphetamines, getting high on the drugs and staying awake all night, then remaining exhausted and furious all day while tasked with caring for Tate. Lesli often mocked Tate, calling him a “baby” for being excited when his daddy got home at dinnertime; she also tormented Tate by withholding toys and food if his behavior didn’t meet her impossible standards.
Ms. Mishler told the court, “The defendant is manipulative, dishonest, untrustworthy, parasitic, cold, self-centered, and cruel.”
Mara Mischler confers with Sarah Schryer.
(Matt Dayhoff/Journal-Star)Judge Paul Gilfillan listens to Mara Mishler.
(Matt Dayhoff/Journal-Star)
According to Michael Steward, the probation officer who conducted Lesli’s pre-sentencing investigation, Lesli’s blood revealed a high level of methamphetamines when tested on February 19, 2020, the day after Tate was taken to the hospital.
Tate’s maternal grandfather, Doug Kent, told the court his grandson was an engaging and energetic boy who loved to dance, play, and laugh. “Tate was such a good little boy and loved by all — I thought,” he said, frowning at Lesli.
In this situation, Doug said, there were “no winners, only losers,” adding that he missed Tate terribly. “He was my little buddy and always will be.”
Jeremy Thurman sobbed breathlessly during his victim impact statement, remembering what he thought was a happy home. “As I am providing for my family… she was hurting my son while I was at work.” He said that at night, Lesli seemed loving, and he never suspected she was abusing his son. “All the while, she was hiding malicious behavior… I have struggled to come to terms knowing I will never hear Tate say, “Daddy, I love you.’”
Calling his ex-girlfriend “a threat to society,” Jeremy told the court he has been diagnosed with severe PTSD since his son’s murder.

(Phil Luciano/Journal-Star)
Jeremy’s aunt, Julie Runyun, said their family would never be the same thanks to the actions of Lesli Jett, who she called “an evil person… I always think about how she made him suffer… I don’t know how my nephew [Jeremy] is ever going to get through this.”
Another witness at the sentencing hearing was Eugenia Small, the grandmother of Lesli’s own son, whose testimony implied Tate was not the only child in the household who was abused. After Tate died, Lesli’s son went to live with Eugenia, who said he had nutritional, speech, and dental issues. The little boy, who required three rotten teeth to be pulled, recoiled in fear when she would “wipe his privates.” He slept all day and stayed up all night, Eugenia testified. One morning, he started hitting himself in the stomach, saying, “Stop, Mom, stop! It hurts!”
Fortunately, the little boy has since developed healthier sleeping habits, and his speech and nutritional patterns have also improved since being in Eugenia’s care.
Lesli’s defense team, attorneys Michael Brandt and Hugh Toner, submitted over 40 letters to the judge from Lesli’s friends and family members, who described her as a decent, kind person who adored children. Asking the judge to give heavy weight to the letters, Brandt said many of the allegations made by the prosecution lacked solid evidence and, of the letters, added, “These folks are genuine.”
Lesli opted not to address the court; instead, she merely submitted a letter to the judge, who read it but did not reveal its contents, merely alluding to her lack of remorse before handing down her sentence. “The fact that she’s not showing remorse… doesn’t necessarily help her here today.”
Judge Gilfillan spoke of Lesli’s egregious behavior toward Tate.” She seemed to be a horrible pseudo-parent for Tate, even before February 18, 2020 rolled around.”

(Matt Dayhoff/Journal-Star)
In Illinois, the sentencing range for first-degree murder is normally from 20 to 60 years, but when the victim is under 12 years old, the convicted can face up to 100 years.
Fortunately seeing through her defense’s attempts to paint her as a saint, Judge Gilfillan sentenced Lesli to 75 years in prison with 18 months credit for time served. By state statute, she is required to serve one hundred percent of her sentence, so she will not be eligible for release until she is about 108 years old, after which she is set to receive three years of supervision.
My guess is she won’t live to see that day, and Lesli Ann Jett will spend the rest of her life exactly where she belongs: suffering behind bars.
Click here for my previous coverage of Tate’s story.
Tate in November of 2017. (Facebook) Tate Thurman. (Facebook) Tate.
(YouTube)
Sources: The Peoria Journal-Star, Central Illinois Proud