CHICAGO (LN) — The Illinois Appellate Court reversed Marcus Thompson’s attempted first-degree murder conviction and ordered a new trial on Tuesday, ruling that jury instructions failed to properly define the specific intent required for the offense following a state supreme court decision.
Thompson was convicted of shooting 16-year-old Tyana Partee after she overpowered his 15-year-old niece, Heavyn Lee, in a fight outside a hair salon in September 2020.
The appellate court’s ruling hinges on the Illinois Supreme Court’s 2025 decision in People v. Guy, which held that the mens rea for attempted first-degree murder is not merely "the intent to kill," but "the intent to kill without lawful justification."
Under Guy, a defendant who subjectively believes they are acting in lawful self-defense or defense of another cannot be convicted of attempted murder, even if that belief is objectively unreasonable.
Justice Ellis, writing for the First District Appellate Court, noted that the Illinois Pattern Jury Instructions (IPI) given to Thompson’s jury incorrectly stated the mens rea element by omitting the "without lawful justification" qualifier. The court stated that the IPI instructions, which specify a mens rea element of "the intent to kill an individual," are wrong on their face because they misstate an essential element of the crime.
The State conceded that the instructional error was consequential because Thompson’s defense theory was that he shot Partee in lawful defense of his niece.
Video footage showed Thompson firing a single shot at Partee from about six feet away, seven seconds after a bystander broke up the fight between the two girls. Partee testified that Thompson pointed the gun at her a second time, but it did not fire.
Thompson’s trial court had instructed the jury on the affirmative defense of justifiable use of force, finding sufficient evidence to submit the issue to the jury. However, defense counsel did not object to the attempted-murder instructions at trial, meaning the error was forfeited.
The appellate court found the error reviewable as plain error, noting that the failure to correctly inform the jury of the crime’s elements is a "substantial defect" that deprives the jury of necessary guidance.
The court rejected the State’s argument that the error was harmless because the evidence disproved Thompson’s alleged subjective belief in self-defense.
"The trial court necessarily (if implicitly) found that there was a genuine question of fact, for the jury to resolve, on the issue of defendant’s subjective belief," Ellis wrote.
The court distinguished Thompson’s case from Guy, where the state supreme court reversed the attempted murder conviction outright and entered a conviction for aggravated battery. In Guy, inconsistent verdicts for two victims made a retrial impossible.
Here, the appellate court found no such inconsistency and ruled that double jeopardy did not bar a retrial.
Thompson was sentenced to 35 years in prison for attempted murder, including a 25-year firearm enhancement.