People v. Ackley, 497 Mich. 381

Defendant (Ackley) convicted of first-degree felony murder and first-degree child abuse after his girlfriend’s 3‑year‑old daughter died while in his care; prosecution presented five medical experts attributing death to abusive head trauma (AHT)/shaken baby syndrome (SBS).
No eyewitnesses or direct evidence; the prosecution’s case rested primarily on expert medical testimony; court funded defense expert assistance.
Defense counsel consulted only Dr. Brian Hunter, who told counsel he was not suitable to support the defense theory (short‑fall/accidental injury) and recommended Dr. Mark Shuman (and possibly Dr. Werner Spitz); counsel did not contact them or review medical literature.
Defense called no medical expert at trial; the defense relied on lay testimony and the defendant’s account that the child suffered an accidental fall.
On appeal, a Ginther evidentiary hearing found counsel’s failure to consult appropriate experts unreasonable and the trial court granted a new trial; the Court of Appeals reversed, finding the choice strategic and non‑prejudicial.
Michigan Supreme Court reversed the Court of Appeals: held counsel was objectively deficient for failing to investigate and secure suitable expert assistance and that there was a reasonable probability of a different outcome; convictions vacated and case remanded.

Issue	Plaintiff's Argument (People)	Defendant's Argument (Ackley)	Held
Whether counsel deprived defendant of effective assistance by failing to obtain a suitable defense expert	Counsel’s expert selection was trial strategy; no prejudice because evidence against Ackley was strong	Counsel failed to investigate beyond an expert who opposed defense theory and ignored referrals to qualified experts; expert testimony was critical	Court held counsel’s failure to investigate/retain an expert was objectively unreasonable and not protected strategy
Whether counsel’s consultation only with Dr. Hunter was reasonable investigation	Counsel argued limiting consultation was reasonable and Hunter’s warnings made further contacts unlikely to help	Hunter stated he could not support the defense and expressly recommended other experts; counsel made no further contacts or independent study	Court held counsel’s decision was not the product of adequate investigation and thus deficient
Whether the deficient performance was prejudicial (Strickland prejudice)	No reasonable probability of different outcome given multiple prosecution experts and nonexpert evidence	Absence of defense expert left prosecution experts uncontested; nonexpert evidence was circumstantial and contested; a defense expert was available and would have provided an alternative explanation	Court found a reasonable probability the verdict would differ; prejudice established

Strickland v. Washington, 466 U.S. 668 (establishes two‑prong ineffective assistance test: performance and prejudice)
People v. Ginther, 390 Mich. 436 (procedure for evidentiary hearing on ineffective assistance claims)
People v. Trakhtenberg, 493 Mich. 38 (clarifies standard of review and strong presumption of reasonable strategy)
Kimmelman v. Morrison, 477 U.S. 365 (recognizes single serious error can support ineffective assistance claim)
Hinton v. Alabama, 134 S. Ct. 1081 (counsel must make reasonable efforts to obtain expert assistance; failure can be constitutionally deficient)