## Facts

- Three criminal defendants (Sharpe, Alexander, and Holt) each took a polygraph examination using the Comparison Question Technique (CQT).
- In each case, the defense sought to present expert testimony from polygraph examiner Dr. David Raskin that the defendant was truthful when denying the charged conduct during the CQT examination.
- CQT polygraphs use (1) neutral questions, (2) broad comparison questions about prior similar conduct, and (3) relevant questions about the charged conduct; the method purports to infer deception from comparative physiological responses.
- Sharpe was charged with murder and manslaughter in connection with the death of his girlfriend’s two-year-old son; Raskin concluded Sharpe’s denials were truthful.
- Superior courts reached conflicting results on admissibility: two courts admitted the proffered CQT testimony under Daubert/Coon, while one excluded it.
- The Alaska Supreme Court consolidated the matters to address both the appellate review standard for scientific-evidence rulings and the admissibility of CQT polygraph “truthfulness” testimony.

## Issues

1. What appellate standard of review applies to trial-court rulings admitting or excluding scientific evidence under Daubert and State v. Coon?
2. Whether CQT polygraph evidence—specifically, expert testimony that a defendant was truthful in exculpatory answers during a CQT exam—is sufficiently reliable and scientifically valid to be admissible under Daubert/Coon.

## Decision

- The court adopted a hybrid standard of review for Daubert/Coon rulings:
  - preliminary factual determinations are reviewed for clear error;
  - whether a scientific theory or technique is “scientifically valid” under Daubert/Coon is a legal question reviewed under the court’s independent judgment (de novo);
  - if the technique is scientifically valid, case-specific evidentiary rulings are reviewed for abuse of discretion.
- Applying that framework, the court held CQT polygraph evidence has not been shown sufficiently reliable to satisfy the Daubert/Coon standard.
- As a result, expert testimony opining that the defendants were truthful during CQT polygraph examinations was inadmissible.

## Legal Principles

- Scientific-evidence admissibility under Daubert/Coon contains separable components: factual findings, a legal determination of scientific validity, and discretionary case-specific evidentiary management.
- Appellate courts independently determine whether a scientific technique has been shown scientifically valid for Daubert/Coon purposes; trial courts’ underlying fact findings receive clear-error review.
- CQT polygraph “truthfulness” testimony is not admissible scientific evidence in Alaska because the technique has not been established as sufficiently reliable under Daubert/Coon.

## Conclusion

The Alaska Supreme Court set a hybrid appellate review standard for Daubert/Coon decisions and ruled that CQT polygraph testimony offered to prove a defendant’s truthfulness is inadmissible because the technique has not been shown scientifically reliable.


State v. Sharpe, 435 P.3d 887 (Alaska 2019)