As in State v. Giese, 2014 WI App 92, 356 Wis. 2d 796, 854 N.W.2d 687, retrograde extrapolation testimony from a toxicologist was admissible as evidence of Lagerstrom’s possible blood alcohol content around the time the state alleged he drove his car into a ditch.
Giese involved a challenge to the admission of retrograde extrapolation evidence regarding a driver who was found lying in the road about 3 miles away from his crashed car. He recalled being in a tavern before the crash, but his memory of when he crashed was hazy so the time of driving was uncertain, so the state couldn’t establish Giese’s blood was drawn within 3 hours of driving. Thus, under § 885.235(1g) the state needed expert testimony to show the probative value of the BAC results. The state sought to admit opinion evidence from a toxicologist who did a retrograde extrapolation to determine Giese’s BAC around the time he was believed to have been driving. 356 Wis. 2d 796, ¶¶3-6, 9-12.
The toxicologist in Giese had training and experience in doing retrograde extrapolations, used established models of elimination of alcohol from the body, and made some assumptions about when the crash occurred and about Giese having fully absorbed all the alcohol by the time of the blood draw. Given her education, training, and experience, her testimony was admissible expert opinion evidence under § 907.02(1) despite the fact she made assumptions about the case, as the validity of the assumptions went to the weight of her opinion, not its admissibility. 356 Wis. 2d 796, ¶¶11-12, 15, 23-25, 28.
Like Giese, Lagerstrom was found a distance from his car a couple of hours after the state alleged he had driven it, so the state couldn’t show his blood was drawn within 3 hours of driving and needed to establish probative value of the results by expert testimony. (¶¶3-11, 22). And like Giese, Lagerstrom argued the retrograde extrapolation evidence offered in his case was inadmissible. The court of appeals finds this case indistinguishable from Giese despite Lagerstrom’s attempts to distinguish them:
¶30 …. Lagerstrom argues that Giese is distinguishable because the blood draw in that case “was not done outside of the 3-hour window listed in Wis. Stat. § 885.235(3).” Lagerstrom is mistaken, however, as it was undisputed in Giese that the blood draw occurred more than three hours after the alleged driving and that the test result was therefore inadmissible unless supported by expert testimony. See Giese, 356 Wis. 2d 796, ¶¶9, 12.
¶31 Lagerstrom also argues that Giese is distinguishable because the police in that case “knew the time of offense,” but here the County failed to establish “the exact time” when Lagerstrom operated his vehicle. Lagerstrom overstates the specificity regarding the evidence of the time of the offense in Giese. …. The toxicologist assumed for purposes of her analysis that the crash had occurred between four hours and four and one-half hours before the blood draw. Id., ¶12. She did not, however, know precisely when the crash took place.
¶32 Here, although Lagerstrom is correct that there is no evidence as to the “exact time” he drove his vehicle, there was sufficient evidence to support reasonable inference that the driving occurred sometime between 2:30 a.m. and 3:30 a.m. Bonte testified that he worked at the Pump House until its closing time of 2:30 a.m. on the night in question. [Deputy] Krueger testified that during their conversation at the accident scene, Bonte told him Lagerstrom had “closed the bar” that night. Although Bonte later denied making that statement .., the factual discrepancy as to whether Bonte told Krueger that Lagerstrom had “closed the bar” that night was for the jury to resolve…. If the jurors accepted Krueger’s testimony about Bonte’s statement that Lagerstrom “closed the bar,” they could have reasonably inferred that Lagerstrom operated his vehicle sometime after 2:30 a.m. on the night in question.
¶33 There was also evidence at trial from which the jury could reasonably conclude that the “time of driving” window ended at 3:30 a.m. Bonte testified that after finding Lagerstrom’s vehicle in the ditch, he searched for Lagerstrom for approximately two hours before hearing him yelling at about 5:20 or 5:30 a.m. Based on that testimony, the jury could reasonably conclude that Bonte found Lagerstrom’s vehicle in the ditch at about 3:30 a.m. And, it could therefore reasonably conclude that Lagerstrom drove his vehicle into the ditch sometime between 2:30 a.m., when he left the Pump House, and 3:30 a.m., when Bonte found his vehicle. [Toxocologist] Edwards testified that at 3:00 a.m., during the middle of that time frame, Lagerstrom’s BAC would have been between 0.20 and 0.28. She also testified that Lagerstrom’s BAC would have been above the legal limit of 0.08 both at 2:00 a.m. and 4:00 a.m.
¶34 Lagerstrom also questions Edwards’ assumptions that there was no unabsorbed alcohol in his stomach at the time of driving and that he did not consume any additional alcohol after driving his vehicle into the ditch. Based on the evidence, however, those assumptions were not unreasonable. Bonte testified that he did not see any alcohol when he looked inside Lagerstrom’s vehicle. There was no evidence to indicate that Lagerstrom consumed any alcohol between the time he left his vehicle in the ditch and the time he was found. To the contrary, Krueger testified Lagerstrom expressly stated that he was drinking “[a]t the bar” before driving into the ditch, and that he did not consume any alcohol after leaving the bar, while driving, or after driving into the ditch. In addition, Edwards testified that a person generally absorbs eighty percent of the alcohol he or she consumes within thirty minutes of consumption. On these facts, it was reasonable to assume that there was no unabsorbed alcohol in Lagerstrom’s stomach at the time of driving and that he did not consume any additional alcohol thereafter.
Because the facts and assumptions that the toxicologist in this case relied upon in her retrograde extrapolation analysis were similar to those relied upon by the expert witness in Giese, and because, as in Giese, the expert testimony here was the product of reliable principles and methods and was based on sufficient facts and data, the circuit court properly exercised its discretion and reasonably concluded that Lagerstrom’s objections to the retrograde extrapolation testimony went to its weight, rather than its admissibility. (¶35).