Utah Court of Appeals

Can conflicting blood test results support a DUI conviction? State v. Spencer Explained

2025 UT App 66
No. 20230863-CA
May 8, 2025
Affirmed

Summary

Spencer was convicted of DUI after a blood test showed .08 blood alcohol concentration. He had an independent laboratory retest his blood sample, which showed .079, below the legal limit. The district court convicted Spencer after finding the difference between test results was not statistically significant.

Analysis

In State v. Spencer, the Utah Court of Appeals addressed whether conflicting blood alcohol test results can support a DUI conviction when one test shows results above the legal limit and another shows results below.

Background and Facts

During a traffic stop in August 2018, a deputy detected a strong alcohol odor from Spencer’s vehicle and found open containers of alcohol. After arresting Spencer for suspected DUI, a warranted blood draw was conducted. The Utah Public Health Laboratory tested Spencer’s blood and reported a result of .08 grams of ethanol per 100 milliliters of blood, meeting the legal threshold for per se DUI. Spencer subsequently had his blood independently tested by a Colorado laboratory, which reported .079, below the legal limit. At his bench trial, Spencer was convicted of DUI despite presenting the Colorado test results.

Key Legal Issues

The central issue was whether sufficient evidence supported Spencer’s DUI conviction when two valid blood tests produced conflicting results. Spencer argued the conflicting test results created reasonable doubt about whether his blood alcohol concentration exceeded the legal limit.

Court’s Analysis and Holding

The Court of Appeals applied the clear error standard to Spencer’s insufficient evidence claim from his bench trial. The court emphasized that weighing conflicting evidence is exclusively the factfinder’s role. Importantly, Spencer’s own expert testified that the difference between .079 and .08 was not statistically significant and that the Colorado results confirmed the State’s results “within their measurement of uncertainty.” The court held that Spencer failed to invalidate the State’s test results and merely presented alternative evidence for the factfinder to weigh.

Practice Implications

This decision underscores that presenting contradictory test results alone is insufficient to overturn a DUI conviction. Defense counsel must present evidence that actually invalidates the State’s testing methodology or results, rather than simply offering alternative test results. The ruling also highlights the importance of expert testimony – here, Spencer’s own expert undermined his defense by confirming the statistical validity of both test results.

Original Opinion

Link to Original Case

Case Details

Case Name

State v. Spencer

Citation

2025 UT App 66

Court

Utah Court of Appeals

Case Number

No. 20230863-CA

Date Decided

May 8, 2025

Outcome

Affirmed

Holding

When two valid blood alcohol tests produce conflicting results, the factfinder may weigh the evidence and accept the test result that places the defendant’s blood alcohol concentration above the legal limit for DUI conviction.

Standard of Review

Clear error for claims of insufficient evidence at bench trial

Practice Tip

When challenging blood test results in DUI cases, present evidence that actually invalidates the State’s test rather than merely offering contradictory results, as factfinders may weigh conflicting valid evidence.

Need Appellate Counsel?

Lotus Appellate Law handles appeals before the Utah Court of Appeals, Utah Supreme Court, California Court of Appeal, and the United States Court of Appeals for the Tenth Circuit.

Related Court Opinions

    • Utah Supreme Court

    State v. Pierce

    June 9, 2022

    The district court did not plainly err in allowing the State to impeach defendant’s trial testimony with his consistent but incomplete pre-trial statements to police because federal law on this issue was unsettled at the time of trial.
    • Constitutional Rights (Criminal)
    • |
    • Evidence and Admissibility
    • |
    • Preservation of Error
    • |
    • Standard of Review
    Read More
    • Utah Court of Appeals

    Grimmer & Associates v. NRLA

    September 12, 2024

    An arbitrator does not exceed their authority when they reasonably interpret a choice of law provision requiring application of Utah Rules of Professional Conduct to mean that Utah law determines whether those rules provide decisional criteria for fee disputes, rather than requiring direct application of the rules as fee assessment criteria.
    • Arbitration
    • |
    • Attorney Fees
    • |
    • Contract Interpretation
    • |
    • Standard of Review
    Read More
About these Decision Summaries

Lotus Appellate Law publishes these summaries to keep practitioners informed — not as legal advice. Each case turns on its own facts. If a decision here is relevant to your matter, we’re happy to discuss it.