State v. PrinceÂ, 255 N.C. App. 389

Victim (Perry), a minor, lived with his mother and defendant (Timothy Prince) after defendant moved in; Perry reported multiple incidents where defendant beat him with a bat and flashlight, choked him, and threatened him to keep him silent.
Perry suffered head lacerations requiring staples, a fractured elbow, knee injury, and subconjunctival hemorrhages from asphyxiation; medical records and photographs documented injuries.
Perry initially and family members initially minimized or lied about the cause out of fear; Child Protective Services and later removal and treatment followed.
Nurse Holly Warner (Safe Child Advocacy Center) examined Perry, reviewed records, photographed injuries, recounted Perry’s disclosures, and testified that her diagnosis was child physical abuse consistent with his reported history.
Defendant was indicted for felony child abuse inflicting serious bodily injury and assault by strangulation; jury convicted on child abuse charge and acquitted on strangulation; sentenced to 127–165 months and appealed, arguing expert vouching and ineffective assistance.

Issue	Plaintiff's Argument (State)	Defendant's Argument	Held
Whether Nurse Warner’s testimony impermissibly vouched for Perry’s credibility	Warner’s testimony described her examination, relayed Perry’s disclosures as part of diagnosis, and offered a medical opinion that injuries were from abuse	Warner improperly vouched for witness credibility by repeating that Perry said defendant caused injuries and stating the child’s disclosure was "the evidence"	Testimony did not constitute improper vouching; it was admissible as medical history and diagnosis used to form an expert opinion
Whether counsel’s failure to object to the expert testimony denied defendant effective assistance	State: no objection was required because testimony was proper; thus no prejudice	Counsel’s failure to object to alleged vouching was prejudicial and deprived defendant of effective assistance	No ineffective assistance: because testimony was not objectionable, failure to object cannot be deficient or prejudicial

State v. Goss, 361 N.C. 610 (discusses preservation and plain error review)
State v. Lawrence, 365 N.C. 506 (defines plain error as fundamental and prejudicial)
State v. Jordan, 333 N.C. 431 (appellate burden to show jury likely would reach different result absent error)
State v. Solomon, 340 N.C. 212 (credibility is for the jury; expert opinion on credibility is generally inadmissible)
State v. Ford, 323 N.C. 466 (same principle on jury as sole arbiter of credibility)
State v. Bailey, 89 N.C. App. 212 (distinguishes expert testimony opining on credibility from expert diagnosis based on examination)
Strickland v. Washington, 466 U.S. 668 (establishes ineffective assistance standard)
State v. Odom, 307 N.C. 655 (quoted in defining plain error)