United States v. Kirby.
No. 24-7070. 12/16/2025. E.D.Okla. Judge Phillips. Involuntary Manslaughter in Indian Country—“Under the Influence”—Jury Instructions—Juror Question—Supplemental Instruction.
December 16, 2025
Kirby and his girlfriend, S.B., socialized with friends at a bar, where Kirby drank several beers. The friends then rode off together on a group motorcycle ride. Kirby rode his motorcycle with S.B. on the back. He wore a helmet, but S.B. did not. Kirby drove at or below the speed limit but overshot a sharp curve and left the roadway. To return to the road, his motorcycle’s front wheel had to scale a four- to six-inch ledge up to the pavement. But the wheel failed to do so, pitching the motorcycle forward and tossing both riders. Kirby landed nearby and was able to regain his feet. But S.B. landed across the roadway and lay unresponsive. A responding trooper tested Kirby for horizontal gaze nystagmus, but Kirby didn’t complete the test. Kirby also declined to perform sobriety tests that involved walking or standing on one leg but agreed to take a breathalyzer test. The trooper then asked Kirby to submit to a blood draw, which he agreed to. Kirby’s blood test showed several substances, including opiates, an amphetamine, antidepressants, and drugs indicating marijuana use or cannabis consumption. The blood test also showed a blood alcohol level of .028%, below Oklahoma’s per se limit of .08%. S.B. died from her injuries, and Kirby was charged with involuntary manslaughter in Indian Country. The case went to a jury trial, and the district court instructed the jury that for Kirby to be guilty, it had to find that Kirby was driving “under the combined influence of alcohol and any other intoxicating substance which may render such person incapable of safely driving or operating a motor vehicle.” After deliberating for a few hours, the jury asked the court whether “under the influence” meant Kirby had alcohol and any other intoxicant in his body, or whether the jury had to determine if he was impaired by substances. Kirby’s counsel proposed a supplemental instruction clarifying that the government had to show that the combined influence of alcohol and any other intoxicating substance rendered Kirby incapable of safely driving a motor vehicle. The trial judge responded that the content of the proposed supplemental instruction was already contained within the given instructions’ two references to the Oklahoma DUI statute. The court advised the jury to revisit the instructions already given. A few minutes later, the jury returned a guilty verdict.
On appeal, Kirby argued that the district court erred by not answering the jury’s question because its note revealed the jury’s uncertainty about Oklahoma’s DUI law, which may have led to his wrongful conviction. Under Oklahoma law, the “under the influence” element requires that a driver be incapable of safely operating a motor vehicle, not that a driver has simply ingested a detectible level of intoxicants. Thus, the intoxicants in Kirby’s system had to have rendered him incapable of safely driving at the time of the accident. Here, a reasonable jury could read the given instruction to require either (1) that the intoxicants influenced Kirby to the point that he was incapable of safely driving his motorcycle, or (2) that the intoxicants were merely able to influence people enough to render them incapable of driving safely, regardless of whether they so affected Kirby. Kirby’s jury was obviously uncertain about the meaning of the “under the influence” element, and the district court could have eliminated that uncertainty by supplementing the instructions with Oklahoma law defining that term. Further, the jury’s quick verdict after being told to reread the instructions indicates that it mistakenly believed that Kirby must be found guilty simply for having alcohol and another intoxicant in his system. Accordingly, the district court abused its discretion. And because that error may have led to Kirby’s guilty verdict, it was not harmless.
The conviction was vacated and the case was remanded for further proceedings.