Utah Court of Appeals
Does Utah's DUI statute require proving blood alcohol at the time of driving? State v. Manwaring Explained
Summary
Defendant Manwaring was convicted of DUI after a motorcycle accident where he consented to a pre-arrest portable breath test showing 0.107 BAC and subsequent blood tests confirming elevated BAC. He appealed, challenging the denial of his suppression motion, exclusion of expert testimony about his BAC at the time of driving, and the constitutionality of the DUI statute.
Analysis
In State v. Manwaring, the Utah Court of Appeals addressed a critical distinction in DUI prosecutions under different subsections of Utah’s driving under the influence statute. The case clarified when evidence of blood alcohol concentration at the time of driving is relevant versus when it becomes irrelevant to securing a conviction.
Background and Facts
Manwaring was involved in a motorcycle accident and subsequently investigated for DUI. Officers detected alcohol on his breath and observed three unopened beer cans near his motorcycle. He consented to a pre-arrest portable breath test showing 0.107 BAC, and blood tests conducted approximately two-and-a-half hours after the accident yielded results of 0.105-0.107. The state charged Manwaring under Utah Code section 41-6a-502(1)(a), which prohibits operating a vehicle with sufficient alcohol to produce a BAC of 0.08 or greater “at the time of the test.”
Key Legal Issues
Manwaring raised three main challenges: (1) his consent to the pre-arrest breath test was invalid, (2) the trial court improperly excluded his expert witness who would testify about his BAC at the time of driving, and (3) subsection (1)(a) of the DUI statute is unconstitutionally vague. The case turned on the critical distinction between subsection (1)(a), which focuses on BAC “at the time of the test,” and subsection (1)(c), which requires proof of BAC “at the time of operation.”
Court’s Analysis and Holding
The court affirmed Manwaring’s conviction on all grounds. Regarding consent to the breath test, the court applied a totality of circumstances analysis and found his consent was voluntary where no officer claimed authority to compel the test, exhibited force, or threatened jail for refusal. On the statutory interpretation issue, the court emphasized that subsection (1)(a) plainly requires only that a defendant have sufficient alcohol to produce a 0.08 BAC “at the time of the test,” not at the time of driving. This made expert testimony about absorption rates and extrapolation backwards to determine driving-time BAC irrelevant and properly excluded.
Practice Implications
This decision significantly impacts DUI defense strategies in Utah. Under subsection (1)(a), the traditional defense of arguing the defendant’s BAC was below 0.08 at the time of driving becomes irrelevant. Defense counsel must instead focus on challenging the accuracy of the actual chemical test, attacking the chain of custody, questioning the reliability of testing procedures, or demonstrating that alcohol entered the defendant’s system after driving ceased. The ruling also clarifies that pre-arrest breath tests are permissible with valid consent, even though the implied consent statute does not apply until after arrest.
Case Details
Case Name
State v. Manwaring
Citation
2011 UT App 443
Court
Utah Court of Appeals
Case Number
No. 20090546-CA
Date Decided
December 30, 2011
Outcome
Affirmed
Holding
A DUI defendant’s consent to a pre-arrest portable breath test was voluntary where no officer threatened jail for refusal, and Utah Code section 41-6a-502(1)(a) focuses on blood alcohol concentration at the time of testing, not at the time of driving, making evidence of absorption rates irrelevant.
Standard of Review
Motion to suppress reviewed for correctness; trial court’s factual findings reviewed under clearly erroneous standard; exclusion of expert testimony reviewed for abuse of discretion; limitation of cross-examination reviewed for correctness as to legal rule and abuse of discretion as to application; constitutional challenges reviewed for correctness
Practice Tip
When challenging DUI convictions under Utah Code section 41-6a-502(1)(a), focus on the accuracy and reliability of the actual chemical test rather than attempting to extrapolate backwards to determine BAC at the time of driving, as such evidence is irrelevant under this subsection.
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