Opinion
No. 357976
11-10-2022
PEOPLE of the State of Michigan, Plaintiff-Appellee, v. Cara Christine BOWDEN, Defendant-Appellant.
Ottawa Circuit Court, LC No. 21-044535-AR, Jon A. Van Allsburg, J. Dana Nessel, Attorney General, Fadwa A. Hammoud, Solicitor General, Lee F. Fisher, Prosecuting Attorney, and Tyler D. Mesman, Assistant Prosecuting Attorney, for the people. State Appellate Defender (by Christopher Langholz) for defendant. Christopher D. Tholen for the Prosecuting Attorneys Association of Michigan, Amici Curiae. Ramis J. Wadood, Philip Mayor, Daniel S. Korobkin, and Rohit Rajan for the American Civil Liberties Union Fund of Michigan. Jessica Zimbelman for the State Appellate Defender Office. David Rudoi for Michigan Association of OWI Attorneys. Michael A. Komorn, Southfield, for the Michigan Medical Marihuana Association. Abbott Nicholson, PC, Detroit (by Kristen L. Baiardi) and Randolph T. Barker for the Michigan Sheriffs’ Association. Dominic J. Merino for Mothers Against Drunk Driving. Robert M. Stevenson for the Michigan Association of Chiefs of Police.
Ottawa Circuit Court, LC No. 21-044535-AR, Jon A. Van Allsburg, J.
Dana Nessel, Attorney General, Fadwa A. Hammoud, Solicitor General, Lee F. Fisher, Prosecuting Attorney, and Tyler D. Mesman, Assistant Prosecuting Attorney, for the people.
State Appellate Defender (by Christopher Langholz) for defendant.
Christopher D. Tholen for the Prosecuting Attorneys Association of Michigan, Amici Curiae.
Ramis J. Wadood, Philip Mayor, Daniel S. Korobkin, and Rohit Rajan for the American Civil Liberties Union Fund of Michigan.
Jessica Zimbelman for the State Appellate Defender Office.
David Rudoi for Michigan Association of OWI Attorneys.
Michael A. Komorn, Southfield, for the Michigan Medical Marihuana Association.
Abbott Nicholson, PC, Detroit (by Kristen L. Baiardi) and Randolph T. Barker for the Michigan Sheriffs’ Association.
Dominic J. Merino for Mothers Against Drunk Driving.
Robert M. Stevenson for the Michigan Association of Chiefs of Police.
Before: Borrello, P.J., and M. J. Kelly and Redford, JJ.
Borrello, P.J.
175In this prosecution for operating while intoxicated (OWI), MCL 257.625(1)(a), defendant, Cara Christine Bowden, appeals by interlocutory leave granted the circuit court’s order affirming the district court’s order qualifying Ottawa County Sheriff’s Department Deputy Adam Schaller as an expert drug recognition evaluator (DRE) and holding that Schaller could provide an opinion on whether defendant operated her vehicle under the influence of marijuana176 to a degree that rendered her unsafe to drive. For the reasons set forth in this opinion, we reverse and remand.
People v Bowden, unpublished order of the Court of Appeals, entered September 9, 2021 (Docket No. 357976).
See National Highway Traffic Safety Administration, Identifying Types of Drug Intoxication: Laboratory Evaluation of a Subject-Examination Procedure, DOT HS 806 753 (May 1985).
The record contains indications both that DRE stands for "Drug Recognition Evaluator" and "Drug Recognition Expert." We need not resolve this discrepancy on the proper nomenclature. Instead, we will simply use the abbreviation "DRE" for the sake of simplicity. Furthermore, even if Schaller’s certification designates him as a drug recognition "expert," that label has no bearing on whether he may properly testify as an expert for purposes of MRE 702.
See National Highway Traffic Safety Administration, Field Evaluation of the Los Angeles Police Department Drug Detection Procedure, DOT HS 807 012 (February 1986).
I. BACKGROUND
On December 1, 2020, defendant was stopped by Ottawa County Sheriff’s Department Deputy Monte White for driving with only one working headlight. White was working with Schaller at the time of the traffic stop. According to his testimony, Schaller was certified in Advanced Roadside Impaired Driving Enforcement (ARIDE). White testified at the evidentiary hearing that when he approached defendant, he smelled "an odor of marijuana coming from the driver window and … noticed that [defendant’s] eyes were bloodshot-red." White asked defendant to get out of the vehicle, and White proceeded to administer standardized field sobriety tests (SFSTs). Another Ottawa County Sheriff’s Deputy, Brian Williams, arrived on the scene. After Williams’s arrival at the scene of the stop, Williams administered two additional tests. When questioned, defendant stated that she had smoked marijuana approximately 30 minutes earlier. Schaller observed as defendant completed the tests administered by White and Williams. White testified that he did not observe defendant commit any lane, speed, or other moving violations while she was driving before he initiated the traffic stop. According to Schaller, defendant was asked to rate her "personal feelings of impairment" on a scale of 1 to 10, with "1 being not at all impaired and 10 being the most high that somebody could ever be." Schaller testified, "[S]he personally self-rated herself as feeling at a 3, in terms of a scale of 1 to 10." Defendant was arrested and taken to a hospital to have her blood drawn. At the hospital, 177Schaller administered a DRE evaluation to defendant. Defendant was charged with operating while intoxicated.
As relevant to the issue presented on appeal, the prosecution filed a motion in the district court requesting the court to "declare Deputy Adam Schaller an expert in the field of Drug Evaluation and Classification and be allowed to testify, and provide an expert opinion, as a Drug Recognition Expert." Defendant opposed this motion.
At the evidentiary hearing, Schaller testified that in addition to SFST and ARIDE training, he had completed a DRE training and certification program in 2019. Schaller explained that the DRE program was a "months’ long process" that consisted of "80-plus hours of classroom work where you’re instructed in different medical conditions, observable signs of drug impairment, different types of drugs, [and] biological factors," followed by field work performing the tests and a final examination. Schaller testified that based on his application of the DRE protocols to defendant and the "totality of the circumstances," defendant was impaired by, or under the influence of, marijuana and unable to safely drive a motor vehicle at the time of the traffic stop.
In his testimony, Schaller described the DRE protocol in detail. There are 12 steps: a preliminary breath test, an interview with the arresting officer, a preliminary examination and first pulse check, an eye examination, multiple divided-attention tests, a vital signs and second pulse check, an examination of pupil sizes in various lighting conditions, an examination of muscle tone, a check for injection sights and third pulse check, an interrogation, the DRE officer’s formation of an opinion based on the totality of the facts 178gathered in the previous 10 steps, and the completion of a laboratory toxicology report. There are 7 drug categories identified by the protocol: central nervous system depressants, central nervous system stimulants, hallucinogens, dissociative anesthetics, narcotic analgesics, inhalants, and cannabis.
Schaller also explained the reasons for completing each of the 12 steps. The preliminary breath test is conducted to determine whether the person is under the influence of alcohol. An interview of the arresting officer provides facts and obser- vations about the subject from the scene in instances where Schaller, as the DRE investigator, was not present for the traffic stop and arrest. The preliminary interview involves asking the subject about medical conditions, physical conditions, and medications that might make the subject appear "impaired when they’re not." During this step, the DRE investigator also makes observations of any visible signs of impairment and checks the subject’s pulse for the first time. The eye examination includes checking for horizontal and vertical gaze nystagmus and the eyes’ ability to converge on an object approaching the face. Next, the subject is administered a series of four tests intended to measure the subject’s ability to divide attention, complete multiple tasks, follow directions, accurately perceive time, and maintain physical body control and balance. Schaller explained that these divided-attention tests were relevant to a subject’s driving ability because driving a vehicle requires a driver to divide attention, multitask, and accurately perceive time and distance to share the road with other vehicles. Further, Schaller testified that the various physical examinations were completed because different substances had different physical effects on the body that could be observed during these examinations.
179Schaller admitted that the 2018 SFST manual published by the National Highway Traffic Safety Administration (the NHTSA) indicated that the SFSTs, which were also administered as part of the DRE protocol, had only been validated for indicating impairment by alcohol or a person’s blood alcohol content. Schaller did not know of any scientific studies validating the use of the SFSTs for determining a person’s level of impairment by any other substance.
The referenced portions of this manual were admitted into evidence.
NHTSA, Marijuana-Impaired Driving; A Report to Congress, DOT HS 812 440 (July 2017).
According to Schaller, the SFSTs are incorporated within the divided-attention tests of the DRE protocol.
Marijuana-Impaired Driving: A Report to Congress, pp 7, 11, 13, 27-29.
According to Schaller, the DRE protocol was developed by the Los Angeles Police Department in the late 1970s. Schaller further testified about studies that were conducted regarding the protocol:
So, in 1984, John[s] Hopkins University with [the NHTSA] performed a lab validation study where they had volunteers who were dosed with different categories of drugs at different levels who were evaluated by DRE’s [sic] from the Los Angeles Police Department and through that process they were able to determine, like, a success and error rate and showing that they had a high success rate. And then after that, in 1985, they did a field validation study with the Los Angeles Police Department where 173 individuals who were arrested for impaired driving offenses other than alcohol where blood was collected were evaluated by Drug Recognition Experts, and that was also able to determine an error rate and a positivity rate where they were able to determine the program—the program validity.
Schaller further explained, however, that the studies found the DRE protocol to be successful in determining that a person was "not impaired" but that "in determining that somebody is impaired and to which 180drug category that they’re impaired, they were able to—the error rate would be what they were not able to opine." Schaller stated that the goal of the first study "was to determine whether or not the protocol was a valid method of determining whether people were under the influence … of certain drug categories." The study did not test actual driving ability. According to Schaller, the "key finding" of the 1985 field study "was that the DECP, Drug Evaluation Classification Program, or DRE process or program is a reliable tool for law enforcement to investigate and determine impairment." Schaller also admitted that a substance like marijuana could be present in person’s body without rendering that person "impaired" or "under the influence." Schaller testified:
So, the goal of this program is not to correlate the presence of a substance to impairment; it’s to observe the subject, their demeanor, their physical signs of general indicators of impairment and their performance in a psychophysical test to determine whether or not they are impaired. We use that information that we see to help us determine which type of drug they’re—of the seven categories that they’re impaired by. The—whether or not there’s a drug active in their system is—is only used to confirm—a confirmatory lab to show that our observations of the person were— were valid or correct.
The studies Schaller discussed were admitted into evidence. The conclusion section of the report for the earlier laboratory study states that "[t]his laboratory simulation study does not represent a direct test of the validity of these or related behavioral examination procedures for detecting and identifying drug intoxication in field situations." This study found that the protocol was highly accurate in correctly identifying the class of drug that a subject had taken when the evaluator judged the subject to be intoxicated. The 181study also found that the likelihood that a subject who had been given an active drug would be judged intoxicated by a DRE evaluator depended on the dose of the drug received and that "[j]udgments of drug intoxication were more likely at the higher doses of active drug than at the lower doses."
In the subsequent field study, the report concluded that "DREs were fairly accurate in determining which drug or drug class the suspect had taken." However, the following quotation from the report succinctly illustrates the limitations of this study as relevant to the issues currently before this Court on appeal:
This section discusses the accuracy of the DREs decisions regarding which specific drugs the suspects were under the influence of. It is important to remember that the DREs in this study were examining the suspects for law enforcement purposes. The DREs indicated whether they felt the suspects were "impaired" by drugs (and hence "unable to operate a motor vehicle safely"), and if so, what specific drugs (or drug classes) the suspect was "impaired" by.
There is no way to determine objectively whether the suspects were actually too "impaired" to drive safely. The fact that drugs were found in a suspect’s blood does not necessarily mean the suspect was too impaired to drive safely. Contrary to the case with alcohol, we do not know what quantity of a drug in blood implies impairment. Thus, this study can only determine whether a drug was present or absent from a suspect’s blood when the DRE said the suspect was impaired by that drug.
Furthermore, the report also stated:
This field evaluation of the LAPD drug recognition procedure was designed to determine whether trained officers could accurately judge the presence of drugs other than alcohol in impaired driving suspects, and whether 182the screening procedure allowed the officers to differentiate between different drugs (or drug classes).
* * *
The results of the two studies conducted by NHTSA appear to show that
the LAPD drug recognition procedure provides the trained police officer with the ability to accurately recognize the symptoms of many types of drug use by drivers. When the officers identify a suspect as having used particular drugs a blood test almost always will confirm their judgement.
A 2017 report from the NHTSA to Congress, titled Marijuana-Impaired Driving: A Report to Congress, was also admitted into evidence at the hearing. This report began by comparing what is known about marijuana-impaired driving with what is known about alcohol-impaired driving because "the effects of alcohol on driving performance and crash risk are relatively well understood …." Noting the intense interest and wealth of research studies devoted to alcohol-impaired driving over a more than 60-year period, the report explained how alcohol is absorbed and eliminated by the body and summarized the well-established correlation between alcohol concentration in the blood or breath and the degree to which driving skills become impaired. The research establishing this correlation involved "studies of alcohol-impaired driving related skills, primarily through laboratory studies involving subjects dosed on alcohol, using psychomotor tasks (reaction time, tracking, target detection), driving simulators and drivers on closed courses in instrumented vehicles, epidemiological studies including roadside surveys of alcohol use by drivers, and studies of alcohol use by crash-involved drivers."
In contrast, the report explains, marijuana is processed by the body in significantly different ways, and 183the effects of marijuana use on driving-related skills have yet to be extensively studied. According to the report, there was research that had "demonstrated the potential of marijuana to impair driving related skills," but the research did not show a relationship between impairment and levels of delta-9-tetrahydrocannabinal (THC). Studies examining the relationship between THC blood levels and degree of impairment had consistently found that "the level of THC in the blood and the degree of impairment do not appear to be closely related" and that "[p]eak impairment does not occur when THC concentration in the blood is at or near peak levels" Further, "[p]eak THC level can occur when low impairment is measured, and high impairment can be measured when THC level is low." The report also indicated that "[c]urrent knowledge about the effects of marijuana on driving is insufficient to allow specification of a simple measure of driving impairment outside of controlled conditions" and that "there are currently no evidence-based methods to detect marijuana-impaired driving." The report’s general conclusion as relevant to the issues currently before us is aptly summarized in the following quotation:
THC is the primary psychoactive substance in marijuana.
Id. at 11, 13, 22.
Currently, there is no impairment standard for drivers under the influence of marijuana. Many of the reasons for this are discussed elsewhere in this report. They include the fact that there is no chemical test for marijuana impairment, like a BAC or BrAC test for alcohol that quantifies the amount of alcohol in their body, indicates the degree of impairment, and the risk of crash involvement that results from the use of alcohol. The psychoactive ingredient in marijuana, delta-9-tetrahydrocannabinal (THC), does not correlate well with impairment…. 184Without a chemical test, the alternative is to develop a psychomotor, behavioral or cognitive test that would in
dicate the degree of driving impairment and elevated risk of crash involvement due to marijuana use. As was described earlier in this report, marijuana has been show [sic] to impair critical driving related skills including psychomotor abilities like reaction time, tracking ability, and target detection, cognitive skills like judgment, anticipation, and divided attention, and executive functions like route planning and risk taking. However, available research does not support the development of such a psychomotor, behavioral or cognitive test that would be practical and feasible for law enforcement use at this time. It is certainly possible that when more research has been conducted on the impairing effects of marijuana use on driving, that can be shown to increase the risk of crash involvement, that it may be possible to develop such a test in the future.
NHTSA, and others, are currently conducting research toward that goal. We are funding a controlled dosing study of different ways to measure marijuana impairment in driving related skills in the hope that some of these measures will be amenable to use by law enforcement. The first step is to show that everyone dosed on marijuana shows an observable amount of impairment in a controlled laboratory setting. The next step would be to develop simplified versions of these measures that do not require sophisticated and expensive equipment that are suitable for field use by law enforcement. The last step would be to establish the relationship between the observed impairment on these tests and elevated risk of crash involvement. Success in the near term is not guaranteed, but possible.
The district court concluded that Schaller could testify as "a DRE expert." Specifically, the district court found that based on the two studies of the DRE program from the 1980s, the DRE program was "sufficiently reliable to meet the requirements of MRE 702." The district court further stated, in relevant part:
185The court finds Deputy Schaller has been trained in accordance with the national standards and he performed the DRE protocol proficiently. He may testify as to his observations of a defendant’s acts, conduct, and appearance, and to give an opinion on the defendant’s state of impairment based on those observations. He may express an opinion that a suspect’s behavior and physical attributes are or are not consistent with the behavioral and physical signs associated with certain categories of drugs.
Defendant sought and was granted leave to appeal in the circuit court, and the circuit court affirmed the district court’s order. The circuit court concluded that Schaller’s testimony regarding the DRE protocol satisfied the relevance and reliability requirements of MRE 702 based on the evidence submitted at the hearing in the district court and based on the acceptance of the DRE program by courts in other jurisdictions.
This Court subsequently granted defendant leave to appeal the circuit court’s order.
II. STANDARD OF REVIEW
[1–4] An appellate court reviews a lower court’s decision to admit or exclude expert testimony for an abuse of discretion. People v Dobek, 274 Mich App 58, 93, 732 N.W.2d 546 (2007). An abuse of discretion occurs when the court’s decision falls outside the range of reasonable and principled outcomes. People v Unger, 278 Mich App 210, 217, 749 N.W.2d 272 (2008). We review de novo preliminary questions of law, such as whether a rule of evidence precludes the admission of particular evi- dence and any issues involving interpretation of the Michigan Rules of Evidence. People v Muhammad, 326 Mich App 40, 47, 931 N.W.2d 20 (2018); Dobek, 274 Mich App at 93, 732 N.W.2d 546. "A trial court necessarily abuses its discretion186 when the court permits the introduction of evidence that is inadmissible as a matter of law." Dobek, 274 Mich App at 93, 732 N.W.2d 546.
III. ANALYSIS
[5] Defendant maintains on appeal that the proposed expert testimony of Schaller regarding his application of the DRE protocol and the opinion he formed of defendant’s state of impairment due to marijuana is inadmissible under MRE 702.
MRE 702 provides:
If the court determines that scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training, or education may testify thereto in the form of an opinion or otherwise if (1) the testimony is based on sufficient facts or data, (2) the testimony is the product of reliable principles and methods, and (3) the witness has applied the principles and methods reliably to the facts of the case.
[6–8] MRE 702 imposes an obligation on the trial court to ensure that any expert testimony that is admitted at trial is reliable. Gilbert v DaimlerChrysler Corp, 470 Mich. 749, 780, 685 N.W.2d 391 (2004). Although the exercise of this gatekeeper role is within a trial court’s discretion, the court may neither abandon this role nor perform it inadequately. Id. Under MRE 702, the trial court is required to "ensure that each aspect of an expert witness’s proffered testimony—including the data underlying the expert’s theories and the methodology by which the expert draws conclusions from that data—is reliable." Id. at 779, 685 N.W.2d 391.
[9–12] "MRE 702 incorporates the standards of reliability that the United States Supreme Court established in 187 Daubert v Merrell Dow Pharm., Inc., 509 U.S. 579, 113 S Ct 2786, 125 L Ed 2d 469 (1993), in interpreting the equivalent federal rule of evidence." Muhammad, 326 Mich App at 51-52, 931 N.W.2d 20.
Under Daubert, a trial court must "determine at the outset … whether the expert is proposing to testify to (1) scientific knowledge that (2) will assist the trier of fact to understand or determine a fact in issue." Daubert, 509 U.S. at 592, 113 S.Ct. 2786. "This entails a preliminary assessment of whether the reasoning or methodology underlying the testimony is scientifically valid and of whether that reasoning or methodology properly can be applied to the facts in issue." Id. at 592-593, 113 S Ct 2786. Some factors that bear on the trial court’s inquiry include: (1) whether the scientific knowledge or technique can, and has been, tested, (2) "whether the theory or technique has been subjected to peer review and publication," (3) "the known or potential rate of error," (4) "the existence and maintenance of standards controlling the technique’s operation," and (5) whether there is "general acceptance" of the scientific technique. Id. at 593-594, 113 S Ct 2786. However, these factors are not exclusive; instead, "[m]any factors will bear on the inquiry …." Id. at 593, 113 S Ct 2786. [Muhammad, 326 Mich App at 52, 931 N.W.2d 20.]
[13–16] This inquiry is a "flexible" one that must focus "solely on principles and methodology" employed, "not on the conclusions that they generate." Daubert, 509 U.S. at 594-595, 113 S.Ct. 2786. Under MRE 702 and Daubert, "the trial court’s role as gatekeeper does not require it to search for absolute truth, to admit only uncontested evidence, or to resolve genuine scientific disputes." Unger, 278 Mich App at 217, 749 N.W.2d 272 (quotation marks and citation omitted). Rather, the trial court’s role is to filter out evidence that is unreliable, with the relevant inquiry being "whether the opinion is rationally derived from a sound foundation." Id. (quotation marks and citation omitted). "Daubert’s general holding—setting forth the trial judge’s general ‘gatekeeping’ obligation—applies not 188only to testimony based on ‘scientific’ knowledge, but also to testimony based on ‘technical’ and ‘other specialized’ knowledge." Kumho Tire Co, Ltd v Carmichael, 526 U.S. 137, 141, 119 S Ct 1167, 143 L Ed 2d 238 (1999). The party offering the expert testimony bears the burden of satisfying MRE 702 and establishing admissibility of the proposed evidence. Gilbert, 470 Mich. at 781, 789, 685 N.W.2d 391.
Defendant was charged in this case with OWI under MCL 257.625(1)(a), which provides as follows:
(1) A person, whether licensed or not, shall not operate a vehicle on a highway or other place open to the general public or generally accessible to motor vehicles, including an area designated for the parking of vehicles, within this state if the person is operating while intoxicated. As used in this section, "operating while intoxicated" means any of the following:
(a) The person is under the influence of alcoholic liquor, a controlled substance, or other intoxicating substance or a combination of alcoholic liquor, a controlled substance, or other intoxicating substance. [Emphasis added.]
[17] To prove a person was "under the influence" of alcoholic liquor, a controlled substance, or other intoxicating substance, the prosecution "must prove that defendant’s ability to drive was substantially and materially affected by consumption" of the relevant substance. People v Lambert, 395 Mich. 296, 305, 235 N.W.2d 338 (1975) (quotation marks omitted); see also People v Dupre, 335 Mich App 126, 131-132, 966 N.W.2d 200 (2020).
Here, defendant argues that the prosecution "has yet to point to a study that correlates the opinion of a DRE evaluator to actual degradation of a subjects’ [sic] ability to safely operate a motor vehicle." Defendant and amicus contend that the DRE protocol has not 189been validated as a reliable tool for determining whether a person’s ability to drive has been impaired by marijuana and that Schaller’s opinion is thus inadmissible under MRE 702 because it is based on unreliable principles and methodologies. Defendant argues that the studies on which the prosecution relied only validated the DRE protocol’s accuracy in determining the presence of a substance in a subject’s blood but did not validate the DRE protocol for determining a subject’s degree of impairment. We agree.
It is apparent from the record that the prosecution did not present any evidence in the district court to show that the DRE protocol had been validated as a reliable method for demonstrating a person’s level of impairment due to marijuana or the degree to which a person’s driving abilities could be diminished by any given level of marijuana. The studies on which the prosecution relied demonstrated the DRE protocol’s level of accuracy with respect to determining whether a particular type of substance was present in a person’s blood, but neither of the submitted reports purported to even address the question of how particular levels of marijuana impacted a person’s ability to drive or rendered a person "impaired." Indeed, the determination under the DRE protocol that a person is "impaired" and unable to safely drive a car appears to be ultimately based on the DRE officer’s subjective judgment, and there is no evidence in this record that the ability of a person to make such a judgment based on the application of the DRE protocol has been tested to demonstrate the accuracy and validity of reaching such a conclusion on a person’s level of impairment due to marijuana.
Additionally, in the 2017 report to Congress, the NHTSA wrote that, although research has shown that 190marijuana has the potential to impair one’s ability to drive, there were "currently no evidence-based methods to detect marijuana-impaired driving." This report also stated that the available research did not yet support the development of a practical and feasible "psychomotor, behavioral or cognitive test that would indicate the degree of driving impairment and elevated risk of crash involvement due to marijuana use."
It bears repeating that the earlier field study—on which the prosecution relies— contained the following disclaimer:
This section discusses the accuracy of the DREs decisions regarding which specific drugs the suspects were under the influence of. It is important to remember that the DREs in this study were examining the suspects for law enforcement purposes. The DREs indicated whether they felt the suspects were "impaired" by drugs (and hence "unable to operate a motor vehicle safely"), and if so, what specific drugs (or drug classes) the suspect was "impaired" by.
There is no way to determine objectively whether the suspects were actually too "impaired" to drive safely. The fact that drugs were found in a suspect’s blood does not necessarily mean the suspect was too impaired to drive safely. Contrary to the case with alcohol, we do not know what quantity of a drug in blood implies impairment. Thus, this study can only determine whether a drug was present or absent from a suspect’s blood when the DRE said the suspect was impaired by that drug.
[18] The prosecution did not present any evidence that the DRE protocol has been tested, or has a known error rate, with respect to the purpose for which the prosecution intended to use the results of the protocol in this case—to provide evidence of defendant’s level of impairment and impaired driving ability. See Muhammad, 326 Mich App at 52, 931 N.W.2d 20. There simply is no evidence in this 191record to support that the DRE protocol can reliably be used to detect the degree or level of intoxication caused by marijuana and determine whether that level of intoxication has made the person unable to safely drive a motor vehicle. Our Supreme Court has explained that because "MRE 702 mandates a searching inquiry, not just of the data underlying expert testimony, but also of the manner in which the expert interprets and extrapolates from those data," it is therefore "insufficient for the proponent of expert opinion merely to show that the opinion rests on data viewed as legitimate in the context of a particular area of expertise …." Gilbert, 470 Mich. at 782, 685 N.W.2d 391. "The proponent must also show that any opinion based on those data expresses conclusions reached through reliable principles and methodology." Id. Moreover, the court’s "gatekeeping inquiry must be tied to the facts of a particular case," Kumho Tire, 526 U.S. at 150, 119 S.Ct. 1167 (quotation marks and citation omitted), and there must be "‘a valid … connection to the pertinent inquiry as a precondition to admissibility,’" id. at 149, 119 S Ct 1167, quoting Daubert, 509 U.S. at 592, 113 S.Ct. 2786. Here, the prosecution has failed to establish any valid connection between the use of the DRE protocol and a conclusion regarding the degree to which a person’s driving ability was diminished by the use of marijuana.
It is clear from the very evidence the prosecution presented to the district and circuit courts that the prosecution failed to meet its burden to establish the reliability, and thus the admissibility, of the proposed expert testimony. See Gilbert, 470 Mich. at 779-781, 192789, 685 N.W.2d 391; Muhammad, 326 Mich App at 52, 931 N.W.2d 20. Therefore, the proposed expert testimony was inadmissible under MRE 702.
We note that this conclusion does not preclude the prosecution from introducing Schaller’s testimony as a lay witness to the extent that testimony is otherwise admissible. Contrary to the apparent concern of our dissenting colleague, our holding is not a blanket prohibition on Schaller’s testimony. We simply hold that Schaller cannot provide expert testimony under MRE 702 regarding his application of the DRE protocol and the opinion he formed of defendant’s state of impairment due to marijuana.
Id. at 9, 27-28. The report states: The lack of an "impairment standard" equivalent to [blood alcohol concentration] level does not prevent the successful prosecution of a marijuana-impaired driver. The lack of toxicological evidence simply means that the officer has to offer other evidence that the driver was under the influence of marijuana too impaired to drive safely. [Id. at 28.]
Reversed and remanded for further proceedings that are consistent with this opinion. We do not retain jurisdiction.
M. J. Kelly, J., concurred with Borrello, P.J.
Redford, J. (dissenting)
From the majority opinion I respectfully dissent. I conclude that the circuit court correctly affirmed the district court’s order qualifying Deputy Adam Schaller as an expert Drug Recognition Evaluator (DRE) permitted to provide an opinion on whether defendant operated her vehicle under the influence of marijuana to a degree that rendered her unsafe to drive. Defendant argues that Deputy Schaller should be precluded from testifying regarding her impairment because the DRE protocol does not permit detection of impairment with absolute scientific certainty. The majority agrees that Deputy Schaller’s testimony should be precluded because the studies on which the prosecution relied only validated the DRE protocol’s accuracy in determining the presence of a substance in a subject’s blood but did not validate the DRE protocol for determining a subject’s degree of impairment. I disagree because evidence established that Deputy Schaller can reliably use the DRE protocol 193as an investigative tool, among other tools, to detect a person’s impairment and inability to safely drive a motor vehicle because of marijuana use.
I. FACTUAL BACKGROUND
Deputy Schaller testified that he worked as a deputy safety officer of the Ottawa County Sheriff’s Office since 2004 primarily as a road patrol officer. He received training in standardized field sobriety tests (SFSTs) at the police academy, later became Advanced Roadside Impaired Driving Enforcement (ARIDE) certified, and became certified as a DRE after 80 hours of classroom work involving instruction in medical conditions and observable signs of drug impairment from different drugs. Deputy Schaller then completed fieldwork in which he performed tests on subjects and a final examination. He testified that he did 12 DRE evaluations during his training and 4 additional evaluations during 2019, 45 evaluations in 2020, and had done 3 so far in 2021. He entered his evaluations into the National Highway Traffic Safety Administration’s (NHTSA) data-tracking website, which verified his evaluations as 97% accurate.
Following defendant’s arrest, Deputy Schaller conducted on defendant the 12- step DRE protocol. Deputy Schaller testified that the DRE protocol aids an officer in determining the category of drug of which the suspect might be under the influence. He explained that the modified Romberg test enables the evaluation of the suspect’s ability to follow instructions, the evaluation of the suspect’s ability to divide attention to perform multiple tasks not unlike those tasks experienced when driving a motor vehicle, and the detection of impairment and other observable physical traits indicative of possible impairment. During the walk 194and-turn and one-leg-stand tests, he monitors each aspect of a suspect’s performance, including the suspect’s ability to listen to and follow instructions as well as perform the steps of each test without interruption, miscue, or need to balance, pause, or stop. The finger-to-nose test, another divided-attention test, tests whether the suspect can follow instructions and do multiple tasks by having the suspect touch alternately the tip of their nose with a fingertip of each hand in the sequence the officer directs. During the Divided Attention Psychophysical Tests administration, Deputy Schaller also looks for observable clues and general indicators—among other things, body tremors, eyelid tremors, jerky movements, imbalance, and abnormal time perception.
After conducting the DRE protocol with defendant following her arrest, Deputy Schaller concluded, based on the totality of all the information obtained in the investigation, that defendant was under the influence of and impaired by marijuana, making her unable to safely operate a motor vehicle. The Ottawa County Sheriff’s Office charged defendant with one count of operating while intoxicated in violation of MCL 257.625(1). Defendant’s toxicology lab test later confirmed that her blood contained delta-9 tetrahydrocannabinol (THC), the active ingredient in marijuana.
Defendant moved in limine in the district court to preclude the introduction of evidence "related to any and all tests of Defendant’s physiology, motor skills, comprehension, or coordination." The prosecution moved in the district court to qualify Deputy Schaller as an expert in the field of Drug Evaluation and Classification and requested that Deputy Schaller be allowed to testify and render expert opinions as a DRE. The district court conducted a two-day evidentiary 195hearing on the parties’ competing motions at which Deputies Monte White, Brian Williams, and Schaller testified. Deputy White testified regarding the traffic stop, his detection of the presence of marijuana, his observance of defendant’s bloodshot eyes, and defendant’s performance during the SFSTs that he administered. Deputy Williams testified regarding defendant’s performance of the tests that he administered. Both deputies testified that they found deficiencies in defendant’s performance of some of the tests, which caused them to believe that probable cause existed to arrest defendant for operating her vehicle while under the influence of a controlled substance in violation of MCL 257.625.
Deputy Schaller testified regarding the training he received to become DRE certified and his experience in performing DRE evaluations. Deputy Schaller testified at length regarding the DRE protocol evaluation process and the development of the DRE protocols in the late 1970s by the Los Angeles Police Department, which later partnered with the NHTSA to perform validation studies in a laboratory setting and in the field with further development over the next 40 years. He explained that around 1984, Johns Hopkins University conducted a lab-based validation double-blind study with 80 volunteers who were administered drugs from specified categories in different doses and then evaluated using the DRE protocol to determine the success and error rate of using that method of detection of drug usage.1a The Johns Hopkins University study is referred to as the Bigelow Study. The study found a 90% success rate in using the DRE protocol for 196determining whether subjects were under the influence of drugs and a 98% success rate in determining if subjects were not impaired.
Deputy Schaller also testified regarding a 1986 field validation study conducted by the Los Angeles Police Department, referred to as the Compton Study,2a in which 173 individuals who had been arrested for impaired-driving offenses other than alcohol were evaluated by DRE experts using the DRE protocol. That study validated the DRE program’s reliability as a tool for use by law enforcement in investigating and determining drug impairment.
Deputy Schaller further testified regarding his observations of defendant during the traffic stop, including that there was an odor of marijuana coming from both defendant and from the vehicle in which she had been the sole occupant, she displayed bloodshot eyes, and she told police officers that she had smoked marijuana 30 minutes before the traffic stop. Deputy Schaller described in detail his observations of defendant’s performance of the SFSTs administered by Deputy White and the ARIDE tests administered by Deputy Williams. Deputy Schaller explained that before he administered the DRE protocol, he felt that probable cause existed to believe that defendant operated her vehicle under the influence of marijuana. He testified that defendant’s performance of the tests under the DRE protocol confirmed that defendant operated her vehicle while impaired. He testified that, in his expert opinion, based on the totality of the information obtained during the investigation, defendant197 was under the influence of marijuana and unable to safely operate a motor vehicle.
On cross-examination, Deputy Schaller conceded that persons could have a drug in their system and not be under the influence or impaired. He testified regarding the Bigelow Study and the Compton Study and affirmed that he considered them to be accurate and valid studies. He described in detail the manner in which the Bigelow Study had been conducted under strict controls to permit accurate analysis of the drug-impairment-evaluation process. He acknowledged that he had some limitations as to knowledge of the study’s parameters but explained that the study’s goal was to determine in a lab setting whether the DRE protocol served as a valid method of determining if people were under the influence of certain drugs. He affirmed that the study did not involve subjects actually driving motor vehicles. The DRE protocol tested subjects’ ability to multitask with divided attention, which correlated to operating a vehicle under driving conditions. Deputy Schaller testified that the DRE protocol assisted law enforcement to recognize general signs and indicators of impairment by specific drugs because different drugs affect people in specific ways that can be recognized through the evaluation process. He conceded that the Bigelow Study stated that it did not represent a direct tested validity of the behavioral examination procedures for detecting and identifying drug intoxication in field situations but noted that it also stated that the study provided "valuable scientific information considering the potential accuracy and utility of such procedures." Deputy Schaller repeated his explanation of the DRE 12-step process and how the totality of all the facts guided the formation of his opinion as to drug usage and impairment. He stated that the later toxicology report confirmed the presence 198of a drug substance in the suspects’ bodies but did not confirm the opinion of impairment.
Deputy Schaller also testified regarding the Compton Study, which he stated had been conducted as a field study to evaluate whether the DRE process served as a valid and useful tool for trained law enforcement officers to determine drug impairment in motor vehicle drivers. He explained that the study’s subjects were people who had been arrested and were suspected of being under the influence. The Compton Study determined that the evaluators’ opinions regarding the 173 subjects were 92.5% accurate in matching the blood-test results. The analysis revealed that 49% were completely accurate opinions respecting 85 subjects but that 38% were partially accurate opinions respecting 65 subjects. He explained that some subjects had used a combination of drugs and that the evaluators identified one but not all drugs because that one drug likely masked the other drug in the subjects’ systems. The blood tests revealed more than one drug, and therefore, the evaluators were deemed partially correct. Deputy Schaller affirmed that the study indicated that identification of marijuana through use of the DRE process had a 78% accuracy rate, but other drugs were identified at much lower percentages of accuracy. He explained that the law enforcement officers who participated in the field study derived their impairment opinions from the totality of their observations.
Deputy Schaller testified that the SFSTs were scientifically validated for determining alcohol intoxication and impairment by alcohol. He admitted that he did not know of any validated studies respecting detection of impairment by any other substances. He clarified that the two studies concluded that the DRE protocol is an accurate and reliable tool that enables 199law enforcement officers to make observations and then derive their impairment opinions based on the totality of the circumstances of the entire investigation. He conceded that to his knowledge the DRE protocol had not been scientifically validated for determination of drug impairment. When asked about a 2017 NHTSA report3a to Congress regarding marijuana-impaired driving, after reviewing the report briefly, Deputy Schaller concurred that the report stated that "many studies [had] not shown [that THC caused] impairment on these psychomotor tasks, cognitive and executive functions as have shown statistically significant impairments" and that the report stated that the "set of signs and symptoms (physiological, effects of the eyes, and behavior) that are indicative of marijuana use" were not based on driving impairment. Further, he agreed that the report stated that there were no current evidence-based methods for detecting marijuana-impaired driving.
Deputy Schaller affirmed that he prepared an evaluation form for defendant and explained that he concluded that defendant was impaired by marijuana based on the totality of the investigation from the time of the traffic stop, his encounter with defendant at the scene, his observation of defendant’s performance of the tests administered at the scene, interactions with her, statements that she made, evidence in the vehicle, and then the DRE evaluation process. He explained that defendant exhibited visible signs of being under the influence of marijuana—including marijuana odor coming from her person and from her vehicle and reddened, bloodshot eyes—and stated that defendant admitted to using marijuana 30 minutes before the 200traffic stop. Deputy Schaller testified that he observed defendant’s performance of the SFSTs administered by Deputy White and observed defendant’s performance of the ARIDE tests Deputy Williams administered. Defendant also rated her degree of impairment as a "3" on a scale of 1 to 10, where 1 signified no impairment and 10 signified the highest degree of impairment one could experience. Deputy Schaller considered relevant defendant’s admission of feeling impaired by the drug. Deputy Schaller explained that defendant was transported to the hospital, where her blood was drawn, and afterward he administered the drug evaluation. Deputy Schaller stated that at that point, the law enforcement officers definitely had probable cause to believe that defendant was under the influence of drugs.
Deputy Schaller testified that before administering the DRE protocol, he had formed a commonsense judgment that defendant appeared to be under the influence of marijuana based on impairment indicators. He then reiterated all the observable general indicators and signs that indicate marijuana impairment and described how his experience and training enabled him to draw conclusions regarding marijuana-related impairment. He affirmed that he checked defendant’s pupils for dilation, her pulse rate, and her blood pressure because those can be indicative of impairment by marijuana. He testified that defendant’s pupils, pulse rate, and blood pressure were normal. He reiterated that he based his impairment opinion on the totality of the facts and indicators presented.
The district court issued a written opinion in which it first determined that Deputy White could testify as a lay witness regarding his contact with defendant and 201his administration of the SFSTs but that he could not testify as an expert regarding marijuana impairment because of the lack of consensus in the scientific community on the efficacy of using SFSTs to measure marijuana impairment. The district court opined that Deputy White’s testimony had probative value regarding defendant’s balance, coordination, and other skills necessary for safe operation of a motor vehicle. Similarly, the district court ruled that Deputy Williams could testify as a lay witness regarding his observations. The district court then considered whether Deputy Schaller could testify as a drug recognition expert and render a marijuana-impairment opinion under the requirements of MRE 702 and applicable caselaw. The district court reflected on Deputy Schaller’s training and experience and the DRE program’s methodology that he used to evaluate defendant. The district court found that Deputy Schaller’s observations were not a scientific or medical diagnosis but were based on physical signs and behaviors defendant exhibited. The district court concluded that DRE training enabled officers to recognize observable signs, symptoms, and behaviors sufficient to permit the rendering of opinions on a defendant’s state of impairment. The district court found that the Bigelow Study and the Compton Study indicated that officers trained in DRE could identify specific drugs and impairment in the studies’ subjects with a high degree of accuracy, which made the DRE program sufficiently reli- able to meet the MRE 702 requirements. The district court found that Deputy Schaller had "been trained in accordance with the national standards and … performed the DRE protocol proficiently." The district court ruled as follows:
[Deputy Schaller] may testify as to his observations of a defendant’s acts, conduct, and appearance, and to give an 202opinion on the defendant’s state of impairment based on those observations. He may express an opinion that a suspect’s behavior and physical attributes are or are not consistent with the behavioral and physical signs associated with certain categories of drugs.
… Deputy Schaller may testify as a DRE expert.
Defendant sought leave to appeal the district court’s ruling, and the circuit court granted leave. The circuit court analyzed the evidence presented at the district court’s two-day hearing. The circuit court found that defendant’s toxicology report and her admission that she had used marijuana 30 minutes before the traffic stop indisputably established that she internally possessed marijuana, a controlled substance, while operating her motor vehicle. The court considered the applicable law and concluded that the standard of proof for a conviction under MCL 257.625(1) required the prosecution to establish that defendant was "under the influence" while operating a motor vehicle. The circuit court found that the 2017 NHTSA Marijuana-Impaired Driving: A Report to Congress indicated that no test available to law enforcement could determine driving impairment caused by marijuana use because the measurable amount of THC in a person did not correlate with impairment. The circuit court observed that trained DRE officers were being qualified as expert witnesses but that no published Michigan case had addressed or decided the reliability and admissibility of testimony regarding application of the DRE protocol or opinion testimony that marijuana use affected a defendant’s ability to drive and to what degree.
The circuit court next considered whether the district court had properly exercised its gatekeeper role by correctly applying the three-part test under MRE 702 and the factors articulated in Daubert v Merrell Daw 203 Pharm.,Inc., 509 U.S. 579, 592-593, 113 S Ct 2786, 125 L Ed 2d 469 (1993), while recognizing the degree of latitude and discretionary authority trial courts have in determining an expert’s reliability as expressed in Kumho Tire Co, Ltd v Carmichael, 526 U.S. 137, 152-153, 119 S Ct 1167, 143 L Ed 2d 238 (1999), and People v Kowalski, 492 Mich. 106, 120-121, 821 N.W.2d 14 (2012) (opinion by Mary Beth Kelly, J.). The circuit court noted that defendant argued that the DRE protocol lacked relevance and reliability because it did not do what it purported to do, i.e., prove that defendant’s marijuana intoxication affected her driving or rendered her "under the influence."
The circuit court analyzed the DRE protocol functions and purpose and noted that its purpose was "not to conclusively determine the presence of a particular drug, which is proved by the results of a toxicology test often received weeks after an arrest, but to determine whether the subject is impaired at the time of the alleged violation by something other than alcohol or a medical condition, and to opine which drug is causing the impairment." The circuit court considered the DRE protocol 12-step process and noted that all DREs conduct it in the same standardized manner and record the results for each step on a standardized form. The circuit court found that only DRE-trained officers who achieved a 75% corroboration rate were certified and that they were required to maintain a minimum accuracy rate and renew certification every two years.
The circuit court concluded that Deputy Schaller’s testimony regarding his application of the DRE protocol in the present case and his opinion that defendant had been under the influence of marijuana and unsafe to drive met the relevance and reliability requirements of MRE 702. The circuit court concluded from the 204record evidence that Deputy Schaller had the requisite training, specialized knowledge, and experience to identify behavioral and physiological signs of impairment caused by different classes of drugs, plus 17 years’ experience as a road patrol deputy interacting with intoxicated drivers. The circuit court found that sufficient facts and data supported the validity of the DRE protocol and Deputy Schaller’s testimony regarding defendant’s marijuana intoxication. The circuit court concluded that Deputy Schaller formed his opinion based on reliable principles and methods and that his testimony would assist the trier of fact in understanding the effects of marijuana intoxication and in determining a fact in issue. The circuit court observed that the degree of defendant’s intoxication remained a question for the trier of fact to decide as the ultimate arbiter of whether the prosecution proved all the elements of the charged offense.
The circuit court also considered whether the probative value of Deputy Schaller’s proposed testimony would be substantially outweighed by unfair prejudice, confusion of the issues, misleading of the jury, or be needlessly cumulative. The court concluded that it would not. Respecting defendant’s argument that the testimony would be unfairly prejudicial because the jury would attribute undue and preemptive weight to it, the circuit court found no such danger because the trial court could instruct the jury to judge Deputy Schaller’s testimony by the same standard applicable to all witnesses and noted that Deputy Schaller could be subjected to cross-examination and impeachment through presentation of contradictory evidence. The circuit court, therefore, affirmed the district court’s ruling that Deputy Schaller qualified as an expert.
205II. ANALYSIS
Defendant argues that the DRE protocol and its application in her case is inadmissible under MRE 702 because no studies correlate a DRE’s ability to determine the degree of impairment in someone who operates a motor vehicle after using marijuana. Defendant’s argument, although alluring, is unpersuasive.
The admissibility of expert testimony is governed by MRE 702, which provides:
If the court determines that scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training, or education may testify thereto in the form of an opinion or otherwise if (1) the testimony is based on sufficient facts or data, (2) the testimony is the product of reliable principles and methods, and (3) the witness has applied the principles and methods reliably to the facts of the case.
"A court considering whether to admit expert testimony under MRE 702 acts as a gatekeeper and has a fundamental duty to ensure that the proffered expert testimony is both relevant and reliable." Kowalski, 492 Mich. at 120, 821 N.W.2d 14 (opinion by Mary Beth Kelly, J.). The court "must ensure that the [expert] testimony (1) will assist the trier of fact to understand a fact in issue, (2) is provided by an expert qualified in the relevant field of knowledge, and (3) is based on reliable data, principles, and methodologies that are applied reliably to the facts of the case." Id. "The party proffering the expert’s testimony must persuade the court that the expert possesses specialized knowledge which will aid the trier of fact in understanding the evidence or determining a fact in issue." People v Smith, 425 Mich. 98, 112, 387 N.W.2d 814 (1986), citing MRE 702. Spejcialized206 knowledge must be something beyond the common knowledge of the average person. Kowalski, 492 Mich. at 123, 821 N.W.2d 14 (opinion by Mary Beth Kelly, J.). An expert may be qualified by "knowledge, skill, experience, training, or education…." MRE 702. "MRE 702 requires the trial court to ensure that each aspect of an expert witness’s proffered testimony—including the data underlying the expert’s theories and the methodology by which the expert draws conclusions from that data—is reliable." Gilbert v Daimler-Chrysler Corp, 470 Mich. 749, 779, 685 N.W.2d 391 (2004).
In its gatekeeping capacity, the trial court must make "a preliminary assessment of whether the reasoning or methodology underlying the testimony is scientifically valid and of whether that reasoning or methodology properly can be applied to the facts in issue." Daubert, 509 U.S. at 592-593, 113 S.Ct. 2786. This analysis does not hinge on discovering "absolute truth" or resolving "genuine scientific disputes." Chapin v A & L Parts, Inc, 274 Mich App 122, 127, 732 N.W.2d 578 (2007) (opinion by Davis, J.). Even the Daubert Court recognized the unreasonableness of expecting that an expert’s testimony "must be ‘known’ to a certainty; arguably, there are no certainties in science." Daubert, 509 U.S. at 590, 113 S.Ct. 2786.
Trial courts have broad latitude to consider whether the expert’s specialized knowledge or technique has been tested or subjected to peer review and publication, whether the known or potential rate of error has been determined, whether standards exist that control the technique’s operation, and the degree of general acceptance in the relevant expert community, as well as other relevant factors, as part of its determination of the reliability of the expert’s relevant testimony. See id. at 593-594, 113 S Ct 2786; Kumho Tire, 526 U.S. at 151-153, 119 S.Ct. 1167. An 207expert may draw a conclusion from a set of observations based on extensive and specialized experience and knowledge. See Kumho Tire, 526 U.S. at 156, 119 S.Ct. 1167. "[T]he trial court’s role as gatekeeper does not require it to search for absolute truth, to admit only uncontested evidence, or to resolve genuine scientific disputes." People v Unger, 278 Mich App 210, 217, 749 N.W.2d 272 (2008) (quotation marks and citation omitted). "The inquiry is not into whether an expert’s opinion is necessarily correct or universally accepted" but "whether the opinion is rationally derived from a sound foundation." Id. (quotation marks and citation omitted).
Defendant concedes that opinion testimony regarding whether a suspect was impaired would likely assist the trier of fact to determine a fact in issue at trial. She also concedes that Deputy Schaller completed the requisite training and education to be proficient in the DRE protocol. Defendant, however, takes issue with using the DRE analysis because the presence of a drug in a subject’s blood does not necessarily equate to impairment, and she contends that use of the DRE protocol cannot establish the degree of driving impairment with "scientific certainty."
The record indicates that neither the prosecution nor Deputy Schaller represented to the lower courts that use of the DRE protocol, in and of itself, definitively establishes a person’s degree of impair- ment. Nor did Deputy Schaller testify that the DRE protocol’s use led to absolute certainty regarding a person’s drug impairment. Rather, the record indicates that the DRE protocol serves as one of several tools law enforcement uses to determine whether probable cause exists to charge a suspect of violating MCL 257.625(1).
208Evidence presented to the lower courts revealed that the DRE program is a nationally standardized protocol used by specially trained and certified law enforcement officers for identification of intoxication of persons by controlled substances within seven categories of drugs. Officers are trained to follow the 12-step protocol to observe behavioral and physiological indicators to determine the drug that the suspect may have used and to assess the degree of impairment based on the totality of the officer’s relevant observations. The record does not reflect that any dispute exists regarding the indicators of marijuana intoxication, which can include observable physical evidence such as bloodshot eyes, eyelid tremors, pupil size, body tremors, body balance issues, and behavioral indicators such as inattention, inability to follow directions, inability to perform multiple tasks, and altered space and time perception. The record also indicates that NHTSA studies and data collected over many years confirm that the use of the DRE protocol methodology enables highly accurate conclusions regarding drug intoxication.
Defendant relies on some statements made in the 2017 NHTSA report to Congress to argue that because no tests have established the specific level of THC in a person’s blood that affects a person’s ability to safely operate a motor vehicle, the DRE testing protocol completely lacks reliability, requiring exclusion of Deputy Schaller’s testimony. The report indicates that, unlike alcohol, there is no chemical test for marijuana impairment that correlates the level of THC in the blood with the degree of impairment. Consequently, THC blood-test levels cannot serve as an indicator of driver impairment.4a Nevertheless, the report acknowledges209 that smoking marijuana has been shown in many studies to affect a number of driving-related skills, such as reaction time, tracking ability, lane-position variability, and decreased divided-attention-target recognition, and that smoking marijuana impairs cognitive performance, judgment, attention maintenance, executive functioning, and performance on psychomotor tasks.5a Although the report recognizes limitations of the DRE testing protocol because no chemical-based impairment standard exists and that it cannot serve alone as an impairment determiner, the report, nevertheless, acknowledges that the DRE program serves as an aid in law enforcement investigations of suspected drug-impaired-driving cases in which properly trained officers follow good investigatory techniques and carefully document their factual observations.6a The report does not assert anywhere that law enforcement should not use DRE-trained and certified officers as part of drug-impaired-driving case investigation. Rather, it endorses the DRE program as the highest level of training an officer can receive to "identify the signs and symptoms of drug use that could be used to determine whether a suspected impaired driver was impaired by drugs and to rule out other possible causes such as neurological deficits, diseases, and illness." The report is not dispositive on whether the district court erred by qualifying Deputy 210Schaller as an expert or the circuit court’s affirmance of that decision. I find that defendant’s arguments go to the weight of Deputy Schaller’s testimony but not its admissibility.
Id. at 27.
As explained in Kumho Tire, an "expert might draw a conclusion from a set of observations based on extensive and specialized experience." Kumho Tire, 526 U.S. at 156, 119 S.Ct. 1167. Examination of the record in this case reveals that Deputy Schaller had numerous years’ experience as a sheriff’s deputy serving on road patrol during which he investigated and apprehended suspected drug-impaired drivers. He had training and experience in administering SFSTs, was ARIDE certified, was trained and certified in the DRE program, and had administered the DRE testing protocol in the field numerous times. His conclusions regarding a driver’s drug usage and impairment were confirmed in a very high percentage of the cases. The record confirms the district court’s and circuit court’s conclusions that Deputy Schaller had the requisite training, specialized knowledge, and experience to identify behavioral and physiological signs of impairment caused by different classes of drugs, plus 17 years’ experience as a road patrol deputy interacting with intoxicated drivers.
Respecting the sufficiency of the facts and data on which Deputy Schaller relied, we observe that Deputy Schaller testified regarding how he conducted his investigation in this case, which included attending the scene and observing defendant’s traffic stop, observing her bloodshot eyes, smelling the odor of marijuana on her person and in her car, observing her deficient performance of the SFSTs administered by Deputy White, observing her deficient performance of the tests administered by Deputy Williams, and observing defendant211 and collecting data during his administering of the DRE protocol. Deputy Schaller followed the applicable steps in the DRE protocol and documented his findings. Deputy Schaller also considered defendant’s admissions to the investigating officers that she had smoked marijuana 30 minutes before the traffic stop and admitted to the officers in Deputy Schaller’s presence that she felt impaired at Level 3 on a scale of 1 to 10. Deputy Schaller considered all these facts and data obtained during the investigation and concluded that defendant had operated her motor vehicle while under the influence of marijuana and had been impaired to the extent that she could not safely operate her vehicle. Defendant has failed to establish that the facts and data obtained during the investigation by Deputy Schaller lacked accuracy or sufficiency for an experienced law enforcement officer to form an opinion. She does not challenge the deficiencies of her performance on the various tests. Nor does she dispute Deputy Schaller’s testimony that he based his opinions on the totality of the circumstances, not merely the application of the DRE protocol. The record indicates that Deputy Schaller derived his conclusions by applying standardized principles and valid investigative methods to the facts of this case.
I conclude that the district court did not abuse its discretion by finding that sufficient facts and data supported the validity of the DRE protocol and Deputy Schaller’s testimony regarding defendant’s marijuana intoxication based on the totality of the circumstances. Likewise, the circuit court correctly concluded that Deputy Schaller formed his opinions based on reliable principles and methods and properly concluded that his testimony would assist the trier of fact in understanding the effects of marijuana intoxication and in determining a fact in issue. The circuit court also 212correctly understood that the degree of defendant’s intoxication remained a question for the trier of fact to decide in relation to its determination whether the prosecution proved all the elements of the charged offense.
The record supports the district court’s and the circuit court’s conclusions that Deputy Schaller’s testimony is based on sufficient facts and data collected during the investigation, that his testimony is the product of reliable investigatory principles and methods, and that he applied those principles and methods to the facts of this case. The record also supports the courts’ respective conclusions that Deputy Schaller’s testimony will assist the trier of fact to understand a fact in issue. I conclude that Deputy Schaller’s testimony meets the requirements of MRE 702 and applicable law and is therefore admissible. Moreover, to the extent that any concerns exist regarding how the jury should understand his testimony, Deputy Schaller would be subjected to cross-examination and the trial court can ably instruct the jury regarding its consideration of his testimony.
Accordingly, in my opinion, the district court did not abuse its discretion by qualifying Deputy Schaller as an expert to testify regarding whether defendant operated her motor vehicle while under the influence of marijuana and was impaired to a degree that made her unable to safely operate her motor vehicle. The circuit court did not err by affirming the district court’s decision. Accordingly, I would affirm.