State v. Wanda J. Crumpton, 2019-001246

Wanda Crumpton was convicted of possession of marijuana with intent to distribute and distribution within proximity to a school or park after police seized a green leafy substance from her home.
The conviction was based largely on the expert testimony of a retired police sergeant who analyzed the substance using a methodology that the South Carolina Law Enforcement Division (SLED) had deemed unreliable months before trial.
SLED had terminated its marijuana analyst certification program after industrial hemp (with <0.3% THC) was legalized, rendering prior marijuana analysis methods unable to distinguish between illegal marijuana and legal hemp.
The trial judge admitted the expert's testimony over Crumpton's objections regarding the reliability of the testing method and conducted the gatekeeping reliability analysis in the presence of the jury.
Crumpton appealed, arguing the expert's report and identification of the substance as marijuana were inadmissible due to SLED's revocation of the testing method, and the trial court's failure to properly determine reliability outside the jury's presence.
The Court of Appeals reversed the convictions, finding the trial court abused its discretion by admitting expert testimony based on an unreliable method without a proper pre-admission reliability review.

Issue	Crumpton's Argument	State's Argument	Held
Admission of Expert Testimony	Method was unreliable per SLED; not sufficient under Rule 702	Method was standard at testing; still valid for prior tests	Error to admit testimony based on unreliable method
Gatekeeping Under Rule 702	Court failed to conduct threshold analysis outside the jury	Reliability is a jury question once expert is qualified	Reliability vetting must be done by court, outside jury
Qualification of Expert	Did not challenge expert’s qualifications after oral argument	Expert is properly qualified based on experience and training	Expert qualifications upheld
Harmless Error	Identification of substance was crucial to conviction	Error, if any, was harmless given other evidence and admissions	Error was not harmless; contributed to verdict

State v. Herrera, 425 S.C. 558 (S.C. 2019) (abuse of discretion standard for evidentiary rulings)
State v. Tapp, 398 S.C. 376 (S.C. 2012) (trial judge must vet reliability of expert testimony before admission)
State v. Mealor, 425 S.C. 625 (S.C. Ct. App. 2019) (setting out Rule 702 requirements for expert testimony)
State v. White, 382 S.C. 265 (S.C. 2009) (reliability is threshold for expert testimony admissibility)
State v. Chavis, 412 S.C. 101 (S.C. 2015) (abuse of discretion occurs if legal error or unsupported facts)
State v. Ellis, 345 S.C. 175 (S.C. 2001) (improper opinion affecting the heart of the case is not harmless)