Michigan v. Madison

Brief Filed: 3/25
Court: Supreme Court of Michigan
Year of Decision: 2026

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Whether scientific evidence of mental illness should be admissible to negate the specific intent element of a charged crime.

Insanity Defense/Diminished Capacity

This case involves a defendant, Cinecca Daquan Madison, who is accused of fatally shooting one acquaintance and wounding another. He is awaiting trial on charges of open murder, assault with intent to murder, and two counts of felony-firearm. The defendant filed a pretrial motion to admit evidence of his diminished capacity to form the specific intent required for the charged offenses. Three mental health experts have examined the defendant and determined that although he suffers from schizophrenia, he was not legally insane at the time of the shooting. At the time of the incident, Madison suffered from untreated schizophrenia and experienced powerful paranoid delusions, hearing voices—including “evil whisper[s]”—and “sounds of weapons” in his home. Immediately before the homicide, Madison claims he saw the decedent “clutching” a firearm and heard another individual say “get em.” The trial court denied the defendant's motion, citing People v. Carpenter, a 2001 Michigan Supreme Court case that prohibits defendants from presenting evidence of mental illness to negate the specific-intent element of a charged crime. The Michigan Supreme Court has ordered briefing and oral argument to address: (1) whether People v. Carpenter was correctly decided and, if not, (2) whether Carpenter should nonetheless be retained under principles of stare decisis.

A substantial body of scientific evidence demonstrates that symptoms of mental illness can impair an individual's ability to form the specific intent that is an element of certain crimes, even when the individual would not be considered legally insane. APA argues that Carpenter's categorical bar on scientific evidence of mental illness to support a diminished-capacity defense ignores well-established empirical reality in the relevant scientific community. The brief details how specific symptoms of mental illness—including information-processing deficits, perceptual disturbances, impulsivity, and cognitive and behavioral disorganization—can impair the ability to premeditate, deliberate, accurately perceive reality, or form the will to execute a plan. APA contends that prohibiting a criminal defendant from advancing a diminished-capacity defense fails to honor legislative choices that have made specific intent an element of certain offenses. This case presents a new opportunity to restore the diminished capacity defense for mentally ill defendants in Michigan, following APA's previous brief in Michigan v. Tyson (2023) which addressed the same issue.

In a significant victory for APA’s position, the Michigan Supreme Court ruled 6–1 that People v. Carpenter was wrongly decided and overruled its prohibition on diminished-capacity evidence. The Court held that Michigan’s legal-insanity statute does not prevent defendants from presenting evidence of mental illness to contest whether they formed the mens rea required for a specific-intent crime. The Court vacated the trial court’s order excluding Madison’s diminished-capacity evidence and remanded the case for further proceedings. The majority expressly relied on and quoted APA and its fellow amici’s explanation that modern science rejects an all-or-nothing spectrum from sanity to insanity and supports the admission of probative mental-health evidence below the threshold of legal insanity. (People v. Madison, slip op. at 20–24, quoting APA Amicus Brief at 5.)