OPINION
*1 Charles A. Lane was convicted, following a jury trial, of driving under the influence and refusal to submit to a chemical test after the skiff he was piloting collided with another boat while he was attempting to dock in Homer.1 On appeal, Lane argues that the district court erred in denying his request to instruct the jury that consuming alcohol after driving a watercraft could be a potential defense against a charge of driving under the influence.2
For the reasons explained here, we conclude that any error in failing to instruct the jury on Lane's chosen defense was harmless beyond a reasonable doubt because Lane presented no evidence to support his post-driving drinking defense. We take this opportunity, however, to address an underlying tension that exists in the current pattern jury instructions that should be corrected in cases where a defendant properly raises a defense of post-driving drinking.
Factual background
Around 10:00 p.m. on April 25, 2021, Harbor Master Sean McGrorty observed a skiff enter the Homer Port & Harbor and “bounce off of the cowling of a couple of outboards of a boat that was parked.” McGrorty drove down to the skiff to look at the damage to the docked boat and to get the phone number of the individual piloting the skiff to make an accident report. McGrorty confirmed with Lane that he was piloting the skiff that made contact with the docked vessel.
McGrorty observed Lane let a female passenger off on the harbor bank. McGrorty noticed that the woman was stumbling, and, despite being around one hundred feet from a restroom, “her pants were around her ankles and she was urinating in a ditch.” At trial, McGrorty testified that he could tell the woman was intoxicated and that he was “more concerned about her” than about Lane. McGrorty observed the woman get into the driver's seat of a truck and drive to the top of the boat launch ramp. Lane got in the passenger's seat of the woman's truck. McGrorty called law enforcement to report the woman for driving the truck while intoxicated.
Approximately eight minutes after McGrorty's 911 call, Homer Police Officer Tyler Jeffres observed a truck matching McGrorty's description. The truck was crossing the fog line and did not have lights on its trailer. Officer Jeffres initiated a traffic stop and made contact with the female driver, Jackie Eisenberg, while another officer, Officer Charles Lee, spoke with Lane, who was sitting in the front passenger seat.
Officer Lee testified that when he made contact with Lane, he noticed that Lane had “watery eyes,” and he requested that Lane roll down the passenger window. According to Officer Lee, “after several requests [Lane] ended up opening the door.” When the door was opened, Officer Lee immediately smelled an odor of alcohol.
*2 Officer Lee confirmed that Lane had been the driver of the skiff and that he and Eisenberg were on their way back from Seldovia. Officer Lee testified that Lane “appeared to be highly intoxicated” and he requested Lane step out of the vehicle to complete field sobriety tests. Lane admitted to drinking two drinks in Seldovia an hour or two earlier.
Lane initially agreed to participate in the field sobriety tests. Lane failed the horizontal gaze nystagmus and the walk-and-turn tests. Officer Lee then began to conduct the one-leg stand test, but Lane refused to continue further testing and instead “turned around and placed his hands behind his back in apparent resignation to arrest.” Because he “believed Mr. Lane was under the influence of alcohol and was impaired while he was operating the boat,” Officer Lee arrested Lane for driving under the influence.
At the police station, Lane refused to provide a breath sample for the DataMaster. However, he requested an independent blood draw. The blood draw revealed a blood alcohol level of .174 percent — i.e., more than twice the legal limit of .08 percent.
Ultimately, Lane was charged with driving under the influence, refusal to submit to a chemical test, and fifth-degree criminal mischief for allegedly spitting in the patrol vehicle.3
Prior proceedings
At trial, Lane's attorney did not contest that Lane was intoxicated at the time of arrest. But the defense attorney asserted that it was possible that Lane and Eisenberg were drinking in the truck after Lane had already parked the skiff and that it was this alleged post-driving drinking that could have accounted for the later over-the-limit blood alcohol test. In other words, the defense attorney argued that Lane's blood alcohol level was not over .08 at the time he was driving the skiff and that it was his post-driving drinking in the truck that accounted for his over-the-limit blood test.
At trial, however, the State established that there was only eight minutes between the time of the harbormaster's 911 call and the traffic stop and therefore limited opportunity for any post-driving drinking. Both officers also testified that they did not find any alcohol bottles or cans in Eisenberg's truck. (Officer Jeffres acknowledged, however, that they did not go back to check the road along Eisenberg's route for disposed bottles or cans.) Lane did not testify.
After the close of evidence, the prosecutor moved for a protective order seeking to preclude Lane's attorney from arguing that Lane had engaged in after-driving drinking. The prosecutor argued that Lane should not be allowed to argue this theory because there was “no evidence” supporting it. The district court denied the motion for a protective order, although it noted that the prosecutor could point out that there was no evidence supporting this claim of post-driving drinking.
During the State's closing argument, the prosecutor argued to the jury that they had to consider whether Lane “knowingly operate[d] a motor vehicle; and was he over .08 at the time that he did so? Or actually, no, not even at the time that he did so. Within four hours.”
Lane objected to the reference to four hours, arguing that the State was required to prove that he was over the legal limit at the time he operated the skiff.
*3 After reading Valentine v. State,4 the court overruled Lane's objection, reasoning that the caselaw was clear that there was criminal liability if the person's blood alcohol is .08 percent “at the time of driving or within ... four hours.” The court therefore ruled that the prosecutor's statement that the State had to prove that Lane had a blood alcohol content of .08 percent or more within four hours of operating the skiff was a correct statement of the law.5
Lane continued to object. He argued that the delayed-absorption defense at issue in Valentine was distinct from a post-driving-drinking defense, and he asserted that the prosecutor was misstating the law in an effort to eliminate his chosen defense. The district court overruled Lane's objection, noting that there was “no evidence ... that Mr. Lane drank between the [harbor] and the stop.”
At this point, the prosecutor realized that the jury had been instructed with a version of the DUI statute that pre-dated the legislative changes discussed in Valentine.6 The court obtained the pattern jury instruction based on the current statute, and then reread the elements instruction to the jury with the current pattern jury instruction. The new instruction stated as follows:
To prove that the defendant committed this crime [of driving under the influence], the state must prove beyond a reasonable doubt each of the following elements:
(1) the defendant knowingly drove or operated a motor vehicle; and
(2) the defendant's blood contained 0.08 percent or more by weight of alcohol or 80 milligrams or more of alcohol per 100 milliliters of blood as determined by a chemical test taken within four hours after the alleged driving or operating.[7]
Lane objected to the updated instruction, arguing that it did not allow for a post-driving-drinking defense. Lane then requested that the court instruct the jury that if it found that Lane drank after driving the boat, the jury could “consider that as evidence of him not being guilty of the crime of DUI.”
The prosecutor objected to the proposed instruction, and the court declined to give it, noting that Lane was free to argue this point during closing argument.
During the defense closing argument, Lane's attorney argued that there was reasonable doubt in his case because it was likely that Lane drank after he operated the boat. The attorney argued that the officers did not do a “whole search” of Eisenberg's truck and that they failed to take pictures proving that there were no alcohol containers in the vehicle.
At one point, the defense attorney began to argue that “what the State has to prove beyond a reasonable doubt is that [Lane] didn't get drunk somewhere between when he got off the ... boat [and his chemical test].” The prosecutor objected, arguing that the defense was improperly creating a new element of the crime. The court agreed and sustained the objection.
*4 In rebuttal, the prosecutor argued that the State had proven beyond a reasonable doubt all of the elements of driving under the influence, and he asserted that there was no evidence supporting the claim that Lane drank after he operated the boat. The prosecutor stated:
So the alternative theory that [Lane] was drinking at some time within the minutes between the harbor and [the location of the traffic stop] enough to become .174 is not a reasonable doubt, ladies and gentlemen. It's not reasonable at all. And additionally, we have seen literally no evidence of that beyond a claim by the [defense] attorney, which again, is not evidence. There is simply no evidence in the record of any kind that there was even alcohol available for Mr. Lane to drink.
Following deliberations, the jury convicted Lane of driving under the influence and refusal to submit to a chemical test. The jury acquitted Lane of the criminal mischief charge.
Overview of relevant DUI law
There are two different legal theories under which a person can be found guilty of driving or operating under the influence under Alaska law: the “under-the-influence theory” under AS 28.35.030(a)(1) and the “blood-alcohol-level theory” under AS 28.35.030(a)(2).8
Under AS 28.35.030(a)(1) (the under-the-influence theory), a defendant is guilty of driving or operating under the influence if they drove or operated a motor vehicle or watercraft “while under the influence of an alcoholic beverage, intoxicating liquor, inhalant, or any controlled substance, singly or in combination.” Prosecutions under this subsection require the State to prove beyond a reasonable doubt that the defendant was under the influence at the time of driving. This can be proved through evidence like indicia of intoxication, poor driving, failed field sobriety tests, and the presumptions contained in AS 28.35.033(a)(3).9
Prior to 2004, prosecutions under AS 28.35.030(a)(2) (the blood-alcohol-level theory) required proof that that the defendant's chemical test was .08 or more at the time of driving.10 In 2004, however, the legislature amended the statute to eliminate a defendant's right to bring a delayed-absorption defense.11 A delayed-absorption defense (also described as the “big gulp” defense) is basically a claim that the post-arrest chemical test did not accurately reflect the person's blood alcohol level at the time of driving because of the delay between a person's consumption of alcohol and the absorption of alcohol into the person's blood stream.12 In other words, because of the delayed absorption, a person who drinks a significant amount of alcohol immediately before driving would not register as over the legal limit at the time of driving, had they been tested then, even though they may have registered over the limit in a chemical test taken hours after the driving.13
*5 In 2004, the Alaska legislature made two changes to AS 28.35.030 to eliminate a defendant's right to bring a delayed-absorption defense.
First, the legislature redefined the blood-alcohol-level theory to eliminate the requirement that the State must prove that the post-arrest chemical test accurately reflected the blood alcohol level of the person at the time of driving.14 Under the post-2004 version of AS 28.35.030(a)(2), a person is guilty of driving under the influence under the blood-alcohol-level theory if the person operates or drives a motor vehicle and “if, as determined by a chemical test taken within four hours after the alleged operating or driving, there is 0.08 percent or more by weight of alcohol in the person's blood.”
Second, the legislature added a new provision to the statute, subsection (s), that eliminated the delayed-absorption defense. However, subsection (s) also made clear that a person could still defend against a driving under the influence charge by asserting that the result of the chemical test was due to drinking that occurred after driving or operating the motor vehicle.15 Subsection (s) states:
In a prosecution under (a) of this section, a person may introduce evidence on the amount of alcohol consumed before or after operating or driving the motor vehicle, aircraft, or watercraft to rebut or explain the results of a chemical test, but the consumption of alcohol before operating or driving may not be used as a defense that the chemical test did not measure the blood alcohol at the time of the operating or driving. Consumption of alcohol after operating or driving the motor vehicle, aircraft, or watercraft may be used to raise such a defense.[16]
In Valentine v. State, the Alaska Supreme Court held that the legislature's elimination of the delayed-absorption defense violated due process when applied to the under-the-influence theory.17 But the court held that the legislature's elimination of the delayed-absorption defense did not violate due process in prosecutions under the blood-alcohol-level theory because the legislature had statutorily redefined the blood-alcohol-level theory of driving under the influence to eliminate the requirement that the State prove that the person's blood alcohol level was .08 percent or over at the time of driving.18
*6 Thus, in a DUI prosecution under the blood-alcohol-level theory, provided that the defense of post-driving drinking is not raised, the State does not need to prove that the chemical test accurately reflected the defendant's blood alcohol level at the time of driving. Instead, as long as the defense of post-driving drinking is not raised, the State need only prove that a chemical test taken within four hours of the person's operating or driving showed that the person's blood alcohol level was .08 percent or more. This is essentially what the current pattern jury instruction for the blood-alcohol-level theory provides.19
But the situation becomes more complicated in cases where there has been a claim of post-driving drinking. We addressed this potential complication in our Valentine decision. In that case, we explained that a defendant was guilty under AS 28.35.030(a)(2) (the blood-alcohol-level theory of driving under the influence) if the defendant's blood alcohol level was over the legal limit as measured by a chemical test taken within four hours of driving and “the test result is attributable to alcohol ingested before or during the operation of a motor vehicle.”20 As we explained,
Under [AS 28.35.030(a)(2)], it does not matter how intoxicated the motorist was at the time of driving. What matters is whether the motorist ingested enough alcohol before or while driving to have a blood alcohol level at or above .08 percent at the time of a chemical test administered within four hours of driving. The defendant may attack the accuracy of the chemical test, or show that alcohol was consumed after driving.[21]
We noted that the legislature has “little interest in penalizing motorists for drinking after driving” and that a defendant could therefore defend against a DUI prosecution under the blood-alcohol-level theory by claiming that “their alcohol-level was above the legal limit at the time of a chemical test because of alcohol they consumed after driving.”22
In other words, to prove a defendant guilty in a case where the defense of post-driving drinking is raised, the State must prove beyond a reasonable doubt that the chemical test taken within four hours of driving would still be .08 percent or higher even subtracting the effect of any alleged post-driving drinking. The State may show this by (1) proving that there was no post-driving drinking; (2) proving that any post-driving drinking was so negligible that it had no effect on the chemical test result; or (3) proving that the test result would still be .08 percent or greater even accounting for the effect of the post-driving drinking on the test results.23
Why we conclude that any error in failing to instruct the jury on Lane's chosen defense was harmless beyond a reasonable doubt
In the current case, Lane asserted that his chemical test was over .08 percent only because he had consumed alcohol as a passenger in the truck after he had operated the skiff. As AS 28.35.030(s) makes clear, post-driving drinking is a valid defense in a prosecution for driving under the influence.
But in order to properly raise this defense, there needs to be “some evidence” of post-driving drinking.24 “Some evidence” is evidence that “viewed in the light most favorable to the defendant, would allow a reasonable juror to find in the defendant's favor on each element of the defense.”25 The defendant's burden of producing “some evidence” is not a heavy one.26 It does not necessarily require the defendant to testify or even offer direct evidence in their own behalf.27 “Some evidence” may arise from weaknesses in the prosecution's evidence or from impeachment of the prosecution's witnesses.28 Once the “some evidence” threshold is met, the trial court must instruct the jury on the proposed defense, and the State must disprove the defense beyond a reasonable doubt.29
*7 Whether “some evidence” warrants an instruction on a proposed defense is a question of law that appellate courts resolve de novo based on the entire record.30
Here, the only evidence to support Lane's post-driving drinking defense was the fact that there was an eight-minute gap between the harbormaster's 911 call and the traffic stop during which time Lane could theoretically have engaged in post-driving drinking. There was otherwise no evidence of any post-driving drinking. Under these circumstances, we conclude that any error in failing to instruct the jury on Lane's post-driving drinking defense was harmless beyond a reasonable doubt because he failed to meet the “some evidence” threshold required for that defense.
That said, we caution trial courts that the “some evidence” test is not intended to be a heavy burden and it is inherently risky to proceed, as the superior court did here, with jury instructions that seemingly preclude the defendant's chosen defense. As we have previously advised trial courts, “ ‘a strong argument can be made that a trial judge should err on the side of giving instructions’ on a proposed defense.”31 Doing so helps guard against potential future reversal of a conviction if the trial court's “some evidence” analysis is flawed. It also ensures that the jury has the benefit of the law that governs a proposed defense (no matter how weak or incredulous the proposed defense may appear to the trial court), and it prevents the jury from applying its own, perhaps misguided, understanding of the proposed defense in the absence of a court instruction to guide its deliberations.32
Given the arguments of counsel in this case, it would have been less confusing if the jury had not received a pattern jury instruction that erroneously suggested that post-driving drinking was not a defense in a prosecution for driving under the influence. We therefore encourage the Criminal Pattern Jury Instructions Committee to revisit the current pattern jury instructions for the blood-alcohol-level theory under AS 28.35.030(a)(2) and to ensure that the tension between the current pattern jury instruction and AS 28.35.030(s) (recognizing the defense of post-driving drinking) is addressed and resolved, at least with respect to cases where the defense of post-driving drinking is properly raised.
Conclusion
The judgment of the district court is AFFIRMED.