State v. MacNeill, 397 P.3d 626

Background

Victim Michele MacNeill died after a post-operative recovery; initial medical examiner ruled death "natural" but later review changed manner to "undetermined" with possible drug toxicity and drowning; State charged husband Martin MacNeill with murder and obstruction.
Prosecution’s case relied heavily on five jailhouse informants who testified that MacNeill admitted or implied he killed his wife; additional circumstantial evidence included alleged overmedication, inconsistent accounts, destruction/alteration of scene and rapid relationship with another woman.
Defense challenged admissibility/credibility of a Children’s Justice Center (CJC) interview of the youngest daughter and moved to exclude or impeach jailhouse witnesses; court excluded the younger child from testifying live but admitted her CJC interview.
Pretrial, the State filed a notice asserting no promises or benefits had been given to federal informants; during trial defense uncovered communications showing investigator Jeff Robinson offered assistance/recommendations to one informant (Inmate One).
After conviction, defense obtained additional federal emails/phone records showing Inmate One expected release in exchange for testimony and Robinson later recommended leniency; MacNeill moved for arrest of judgment or new trial under Brady/Giglio.
Trial court found the State suppressed impeachment evidence (Robinson’s promises), but concluded the undisclosed material was cumulative of impeachment elicited at trial and would not have reasonably changed the verdict; appellate court affirmed.

Issues

Issue	Plaintiff's Argument (State)	Defendant's Argument (MacNeill)	Held
Sufficiency of evidence for murder conviction	The evidence (including jailhouse confessions and forensic/demeanor evidence) supports conviction	Circumstantial evidence insufficient; relied primarily on unreliable jailhouse informants	Affirmed: circumstantial and inmate testimony, plus other evidence, sufficed for jury to convict
Brady/Giglio suppression of impeachment (Inmate One benefits)	Any undisclosed communications were either not known to prosecutors or cumulative of impeachment shown at trial	Prosecutors suppressed material impeachment (promises/recommendations by investigator) that would have created reasonable probability of different outcome	Affirmed: trial court found suppression occurred but nondisclosure was cumulative and not reasonably likely to change result
Violation of witness exclusion order / informant exposure to trial coverage	State contends any procedural lapses did not materially change testimony or prejudice defendant	Federal inmates viewed trial coverage contrary to exclusion order and thus could conform testimony; prejudice resulted	Affirmed: failing to notify inmates promptly did not produce material change or proven prejudice
Additional prosecutorial misconduct / cumulative error	Errors alleged were not prejudicial individually and do not cumulatively undermine fairness	Multiple discovery failures, witness coaching, non-disclosure of alternative suspects denied fair trial	Affirmed: court found no reversible error and cumulative-error claim fails when no prejudicial errors proven

Key Cases Cited

State v. Kruger, 6 P.3d 1116 (Utah 2000) (standard for reviewing jury verdicts)
State v. Nielsen, 326 P.3d 645 (Utah 2014) (circumstantial-evidence review and sufficiency standard)
Brady v. Maryland, 373 U.S. 83 (1963) (prosecution duty to disclose favorable evidence)
Giglio v. United States, 405 U.S. 150 (1972) (impeachment evidence about promises to witnesses must be disclosed)
United States v. Bagley, 473 U.S. 667 (1985) (materiality standard for impeachment evidence)
Tillman v. State, 128 P.3d 1123 (Utah 2005) (cumulative-effect and when impeachment is cumulative for Brady purposes)
State v. Harmon, 956 P.2d 262 (Utah 1998) (standard of review for new trial motions)
State v. Brown, 948 P.2d 337 (Utah 1997) (jury’s role on credibility; circumstantial evidence can suffice)