THE PEOPLE, Plaintiff and Respondent, v. TERRY VANGELDER, Defendant and Appellant.
No. S195423
Supreme Court of California
Nov. 21, 2013
1
COUNSEL
Michael J. Fremont; Bartell & Hensel, Donald J. Bartell and Lara J. Gressley for the California DUI Lawyers Association as Amicus Curiae on behalf of Defendant and Appellant.
Jan I. Goldsmith, City Attorney, Tricia Pummill, Assistant City Attorney, Marlea F. Dell‘Anno and Angie M. Reddish-Day, Division Chiefs, and Jonathan I. Lapin, Deputy City Attorney, for Plaintiff and Respondent.
OPINION
CANTIL-SAKAUYE, C. J.— In this prosecution for driving while having a proscribed alcohol concentration in blood or breath, the trial court excluded expert witness testimony challenging the reliability of breath-alcohol testing machines. Reviewing the ensuing conviction, the Court of Appeal determined that the trial court erred, and reversed for a new trial. We conclude that the trial court properly excluded the challenged expert testimony with respect to the charge of driving while having a proscribed alcohol concentration. Accordingly, we reverse the judgment of the appellate court and affirm the conviction.
I. Facts and procedure
On December 22, 2007, at approximately 2:30 a.m., Sergeant Richard W. Berg of the California Highway Patrol (CHP) observed defendant Terry Vangelder, who was then 50 years of age, driving a high-performance pickup truck more than 125 miles per hour on Highway 163 in San Diego County. Sergeant Berg followed defendant for more than five miles and eventually caught up with him, noticing that he slowed to 100 miles per hour when he approached other traffic and was not weaving outside his lane. After traveling an additional
Defendant provided his license and registration and said, “I was just screwing around.” Berg detected an odor of alcohol and noted that defendant‘s eyes were red and watery. Defendant admitted he had consumed two glasses of wine. Berg called for backup and transferred the matter to two other CHP officers, including Gerald Guzman, who arrived at 2:58 a.m.
Officer Guzman gave defendant field sobriety tests, in which defendant exhibited few signs of impairment. Defendant told Guzman he had three glasses of wine at dinner. Guzman thought defendant smelled of alcohol and noticed that his eyes were red and glassy. Soon thereafter, at approximately 3:10 a.m., defendant consented to two in-field preliminary alcohol screening breath tests using an Intoximeter Alco-Sensor IV. Such a test is “preliminary” in the sense that it is employed—only with the driver‘s actual consent—prior to any arrest, in order to assist an investigating officer in determining whether to arrest the driver.1 Standard testing protocol required that a subject be observed continuously for 15 minutes before the test was administered, in order to make sure that the subject had not during that time ingested alcohol or done anything else that might compromise the test (see
Based on his observations and the preliminary breath tests, Guzman believed that defendant was under the influence of alcohol, arrested him, and transported him to the county jail. There, defendant was subject to additional chemical testing under the implied consent law,
The San Diego City Attorney‘s Office filed a misdemeanor complaint charging defendant with (1) driving under the influence of alcohol in violation of
Prior to trial, defendant filed motions to (1) exclude evidence of the PAS tests to establish blood-alcohol content, asserting they were not conducted in accordance with applicable regulations and were unreliable and (2) allow evidence concerning “partition ratio variability” (described post, pt. II.A.3.) with regard to the generic offense.3 The People filed opposing motions. The trial court deferred ruling on the PAS and partition ratio evidence issues, and the matter proceeded to trial.
A. The People‘s evidence
CHP Officer Brandon Garland, who was responsible for maintaining and calibrating the agency‘s PAS breath-testing devices, testified regarding the
Marissa Ochoa, a criminologist at the San Diego County Sheriff‘s Regional Crime Laboratory, testified that both the particular Intoximeter EC/IR breath-testing machine and the blood sampling device used to test defendant at the county jail were in proper working order when used to take and measure samples from defendant, and that the Intoximeter EC/IR breath-testing machine in question has an operational range within the accepted limits of error (see ante, fn. 4). Ochoa further testified regarding the effect of alcohol on the human body. She was asked to assume that a healthy male weighing 200 pounds had consumed three glasses of wine with a hearty meal between 8:00 and 9:00 p.m., was pulled over while driving at 2:45 a.m., and thereafter at the jailhouse produced a breath test result of 0.08 percent at 3:37 a.m. and a similar blood test result 15 minutes later. She concluded that under normal bodily processing of alcohol, such a “person[‘]s alcohol level [would] be 0.09, approximately, at the time of driving.” On cross-examination, Ochoa explained that if an average healthy male weighing 200 pounds had ingested alcohol only during a dinner between 8:00 and 9:00 p.m., he would have needed to consume approximately 11 drinks (each drink defined as a 12-ounce beer, a 4- to 6-ounce glass of wine, or a 1- to 1.25-ounce serving of hard liquor) in order to have a 0.08 percent blood-alcohol level seven and one-half hours later.
B. Defendant‘s evidence
1. Initial testimony by Dr. Hlastala concerning asserted unreliability of breath-testing machines in light of alcohol that is “picked up” during inhalation before reaching the deep lungs
Defendant called Dr. Michael P. Hlastala, professor of medicine, physiology, biophysics, and bioengineering at the University of Washington, to testify concerning the effects of alcohol on the respiratory system and the reliability of breath-testing machines. Hlastala explained that his field of
Defense counsel asked Dr. Hlastala to assume that both a preliminary “roadside breath test” (i.e., PAS) machine and an “EC/RI” breath-testing machine are “working perfectly, and they‘ve been properly done. Do they provide a scientifically accurate test?” Hlastala replied, “Well, they don‘t.” (Italics added.)
After a sidebar conference, Dr. Hlastala continued by explaining “the way we take oxygen and put it into the body” and “the way we eliminate carbon dioxide” from the body. He used a pen to create a diagram and explained: “Starting from the throat, the windpipe is called the ‘trachea.’ The trachea comes down . . . to just about the heart, . . . and that splits off into a left and right side, and that splitting goes on . . . about 20 times before it gets into the air [sacs]” deep in the lungs, known as the alveolar sacs. “There are about 300 million of these [alveolar sacs] in every valve. They are . . . very tiny. . . . There‘s blood vessels around that and this is where a lot of the action takes place. If we bring outside air with oxygen in it, the oxygen goes into the blood, . . . and then it gets . . . metabolized and that provides energy for us.”
Thereafter, Dr. Hlastala began to testify that even if breath-testing machines operate as designed, they do not perform a scientifically reliable test, because some alcohol present in mucus membranes and bronchial vessels in the upper airways absorbs into the breath before it finally reaches the alveolar sacs in the deep areas of the lungs. Specifically, he stated: “Now, when the breath test was developed in the 1950s, it was understood that if there was alcohol in the blood, that some of it would get out into . . . the [alveolar] air sac[]s and . . . the idea . . . of a breath test” is to take this air originating in the alveolar sacs “and breathe it out, and then measure it . . . with the breath test instrument. [¶¶] The concept is that this alcohol in this [sampled] air, [is] equal to what‘s down in here [in the alveolar sacs], [and] hence [it‘s] related to whatever‘s in the blood. We know, now, that it‘s not quite that simple because alcohol is quite soluble, it goes into water quite easily. And we have, in the airway, a lot of mucus and water and that mucus lining in the airway plays an important role in protecting us from particles and things we inhale[,] goes on to this mucus, then comes out to the mouth.”
In other words, Dr. Hlastala informed the jury that although breath-testing machines are designed to sample and analyze the concentration of alcohol contained in alveolar, deep lung air, they fail to do so. At this point the prosecutor objected to Dr. Hlastala‘s testimony. The trial court excused the jury until later in the afternoon and conducted a hearing regarding the admissibility of the initial and further proposed testimony.
2. Hearing concerning additional proposed testimony by Dr. Hlastala that other physiological factors make breath-testing machines unreliable
Outside the jury‘s presence, the trial court questioned whether testimony by Dr. Hlastala would constitute evidence concerning “partition ratio variability,” which we had earlier held in Bransford, supra, 8 Cal.4th 885, to be inadmissible in prosecutions under the per se statute,
On cross-examination the prosecutor asked: “Doctor, in this case, we have a result from an EC/IR [breath-testing machine] of 0.08. In your opinion, what does that 0.08 measure?” Dr. Hlastala responded: “It‘s measuring the alcohol concentration of the breath that is delivered to the machine.” The prosecutor asked, “Is there any reason to believe, in this case, that [reading] was inaccurate?” Dr. Hlastala responded, “It‘s an inaccuracy in how . . . the alcohol comes out of the mouth” because “from time to time, a person . . . can deliver different amounts of alcohol through the mouth . . . through the breath.”
The prosecutor continued: “So, in your opinion, breath tests are inherently inaccurate as a measure of how much alcohol a person has in them?” (Italics added.) Dr. Hlastala answered: “They are. And primarily because the basic
The prosecutor followed up: “So that . . . wouldn‘t mean that the machine has, in a given sample, not measured it accurately?” Dr. Hlastala responded, “No. I‘m assuming that the machine is working accurately.” He elaborated by stating that breath-testing machines cannot reliably reflect the concentration of alcohol in blood because they constitute “an indirect test” of blood alcohol. He explained that the best sample of blood would be that found in the brain, and that a sample from venous blood “is the next best thing.” As an alternative to such a blood sample, “the breath is the next best thing. [And then] [t]he odor of alcohol is the next best thing. They‘re all remote, the more remote the more variable.”
At this point the court reviewed with Dr. Hlastala the other factors that, according to his proposed testimony, render breath testing scientifically unreliable. In addition to the factors that Hlastala had focused on earlier in the hearing outside the jury‘s presence—pattern of breathing (speed and depth of inhalation), body and breath temperature, and hematocrit level (ratio of red blood cells to total blood volume)—the witness stated that additional relevant factors include sex (explaining that “[w]omen have a smaller lung, therefore a higher breath test relative to that blood“), and “medical condition,” such as “lung diseases.”
The court observed that California law, in correlating breath alcohol with blood alcohol, applies “what‘s known as the ‘standard partition ratio,’ which I understand is grams of alcohol in 210 liters [of breath] equals grams of alcohol per 100 milliliters of blood“—and the court asked the witness if he believed that “the [true] ratio of one person might be different [from the ratio in] someone else?” Dr. Hlastala responded: “That‘s correct. . . . [S]ome people would be different.” The court pressed, asking: “Now, . . . basically what you‘re saying here as to why this [breath-testing machine] test isn‘t scientifically reliable, [is] because it automatically applies this standard partition ratio?” Dr. Hlastala replied: “No, not really. I‘m not talking about the partition ratio. I‘m talking about factors that influence the breath [sample], breath-alcohol [sample], and I‘m not talking about comparing it to blood.”
The court continued, “[I]n this particular case, are you prepared to state that the breath sample of defendant as being 0.08 would be . . . overstating or understating?” Dr. Hlastala responded that it could be either, and that he had no opinion whether defendant‘s breath test result of 0.08 percent was actually (or even probably) overstated or understated.
Although the court appeared to agree with the prosecutor that “at some point” it would instruct the jury not to consider Dr. Hlastala‘s testimony that even if breath-testing machines are working properly, their samples and results are not scientifically reliable due to physiological factors, the court was unwilling to so instruct the jury immediately. Instead, the court said it would “think about it“—but that “[a]t a minimum, I‘m going to instruct counsel not to argue that.”6
Eventually the trial court ruled—over defendant‘s objections—that Dr. Hlastala‘s proposed testimony was speculative and did not materially differ from evidence concerning partition ratio variability, which we had held in Bransford, supra, 8 Cal.4th 885 (discussed post, pt. II.B.2.), to be inadmissible in prosecutions under the per se statute,
3. Resumed limited testimony by Dr. Hlastala
Thereafter, Dr. Hlastala resumed the stand and testified that the presence of mouth alcohol can cause a “false positive test,” meaning a higher result than would be obtained otherwise. Dr. Hlastala also testified that “retrograde extrapolation“—estimating a blood-alcohol level that existed at an earlier time based on a reading at a known later time, as the People‘s witness, Ochoa, had undertaken—was “difficult” to do “over long periods of time.” He did not testify that the particular breath-testing machines used in this case malfunctioned, or that they were improperly calibrated.
4. Testimony by defendant and his son
Defendant‘s 16-year-old son Wesley testified that defendant drank two or three glasses of wine between 8:00 and 9:00 p.m. during dinner at a restaurant. Thereafter, Wesley related, they went for a night hike and returned home about 2:00 a.m., when defendant drank a beer and Wesley went to bed.
Defendant testified that at approximately 2:00 a.m. he drank one beer, and then went out again, driving his vehicle on Interstate 15 and Highway 163. He explained that the night was moonlit, traffic was light, and “I did a burst of speed. . . . And there was no question, I exceeded 100 miles per hour.” Defendant testified that when he was informed by the officer of the results of his breath tests, “I, quite frankly, did not believe, . . . that that‘s what I was at. So I said I wanted to submit to a blood test. I didn‘t think it was accurate. And the reason I say that is because I knew how much I had to drink. I knew what the effects were. I mean, obviously you have a beer you might feel the tingle, but it did not affect my motor skills. It didn‘t affect my burst of speed. That‘s just who I am. I would have done that whether or not I had that beer or not. That‘s just something that would have happened.”
C. Jury deliberations and verdict
During deliberations, the jury inquired whether it was allowed to find a defendant guilty of driving with a blood-alcohol content above 0.08 percent (the per se charge,
Defendant filed a notice of appeal to the appellate division of the superior court. The appellate division denied the appeal, but the Court of Appeal granted defendant‘s application for certification to transfer the case. (
II. Contentions and relevant background principles
The People assert that the appellate court erred both in overturning the trial court‘s exclusion of the prehearing jury testimony and subsequently proffered testimony of Dr. Hlastala, and also in finding the alleged errors to be prejudicial. Defendant, for his part, asserts the trial court erred in excluding the proffered testimony (and argument concerning it) that breath-testing machines are unreliable because even when they operate and are employed as designed, they do not perform a scientifically reliable test. Specifically, as further described post, in part III., defendant presents two general contentions: First, he asserts the trial court erroneously precluded him from presenting as a defense the argument that breath-testing machines are unreliable due to alcohol that is “picked up” during inhalation while traveling past mucus membranes lining the airway before breath reaches the alveolar, deep lung regions—and that, accordingly, the machines fail to sample alcohol contained within alveolar or deep lung air, as required by
A. Scientific principles, assumptions, and corresponding regulations
After ingestion and absorption through the stomach walls and the intestines, ethyl alcohol enters the blood and eventually travels via the carotid arteries to the brain, where it causes intoxication and resulting mental and physical impairment. (McNeal, supra, 46 Cal.4th at pp. 1190–1191; State v. Chun (2008) 194 N.J. 54 [943 A.2d 114, 126] (Chun); see generally Mason & Dubowski, Breath-Alcohol Analysis: Uses, Methods, and Some Forensic Problems—Review and Opinion (1976) 21 J. Forensic Sciences 9 (hereafter Mason and Dubowski, Breath-Alcohol Analysis).) At the same time that absorption of alcohol occurs, elimination also commences through excretion and metabolization. “When a person‘s body is absorbing alcohol faster than he or she is eliminating it, the concentration of alcohol in the blood will continue to rise. . . . The concentration will reach its peak, and it will achieve a plateau, at the time when elimination and absorption are occurring at about the same rate. [¶¶] [Thereafter,] [w]hen the person slows down ingestion to the point where the body is eliminating alcohol more quickly than absorbing it, the body enters what has generally been referred to as the post-absorptive phase. During this period of time, the concentration of alcohol in the blood decreases.” (Chun, supra, 943 A.2d at p. 127.)
1. Sources for measuring alcohol concentration
Although blood in the brain itself—or in the carotid arteries leading to the brain—would be the best source from which to test for the presence of impairing alcohol, as a practical matter it is impossible to acquire such samples. (McNeal, supra, 46 Cal.4th at p. 1191; State v. Downie (1990) 117 N.J. 450 [569 A.2d 242, 246] (Downie).) Instead, tests focus on the next best sources: samples from venous (or capillary) blood, from breath, or from urine. (See, e.g.,
Whereas testing of venous blood directly measures the concentration of alcohol in a person‘s blood, breath and urine testing provide indirect measures for determining the concentration of alcohol in blood.7 The New Jersey
2. “Henry‘s Law” and the target breath sample
Exhaled breath emanating from the region of tiny alveolar sacs deep in the lungs is deemed to reflect “that portion of the expired breath which is in equilibrium with respect to alcohol with the immediately adjacent pulmonary blood.” (
Breath-testing machines are designed to measure breath-alcohol levels in light of the conditions under which Henry‘s Law operates in the alveolar regions deep in the lungs where the gaseous exchange between pulmonary blood and inhaled air occurs. (See generally 2 Defense of Drunk Driving Cases, supra, § 18.01[2][a], p. 18-7; see also Flores et al., Breath Alcohol Sampling Simulator (BASS) for Qualification Testing of Breath Alcohol Measurement Devices (1981) U.S. Dept. of Commerce, National Bureau of Standards Special Publication 480-41, p. 3 [“the alveoli-blood interface is the primary locus for active gas exchange between blood and breath . . .“] (hereafter BASS for Qualification Testing of Breath Alcohol Measurement Devices).) Thus, a target breath sample often is described, as in the relevant federal regulation and in the statutes or regulations of many states, as “deep lung” or “end-expiratory” air or breath—in other words, the last portion of the exhalation of a deep breath.8 Some state provisions describe the same target sample as “alveolar in composition,” “substantially . . . expired alveolar air,” or employ a variation on that terminology.9 Other state provisions combine this terminology, calling for samples of “alveolar or deep lung air,” “deep lung (alveolar) air,” “deep lung breath (substantially alveolar in composition),” or a sample that is “essentially alveolar or end expiratory in composition.”10 The variation employed by California and a few other states
However phrased, the relevant federal and state regulations all require a specimen originating from deep within the lungs—a sample that is considered to most closely reflect the concentration of alcohol passing from the circulating blood into the alveolar sacs. Correspondingly, breath-testing machines have long been designed to capture and measure such a sample, obtained from the last portion of the expired breath. (Dubowski, The Technology of Breath-Alcohol Analysis (1991) U.S. Dept. of Health & Human Services, pub. No. (ADM)92-1728, pp. 5-6.) Subjects are instructed to take and expel a deep breath. (See, e.g., Chun, supra, 943 A.2d at p. 129.) Models like the Intoximeter EC/IR used in this case are designed to indicate whether an adequate sample of end-expiratory breath has been provided—and to prompt the operator to secure a subsequent sample as necessary. (See, e.g., 2 Defense of Drunk Driving Cases, supra, § 18.05[1][b], p. 18-141; see also id., § 19.05[3], pp. 19-10 to 19-11 [describing the “sampling requirements” of the Intoximeter EC/IR used in the present case]; cf. Chun, supra, 943 A.2d at pp. 129–131 [describing procedures used for a related model].)
3. Scientific analysis of breath samples—(a) the blood-alcohol: breath-alcohol partition ratio, and (b) “partition ratio variability”
Scientific analysis of breath samples to determine the concentration of alcohol in blood is premised on a conversion methodology utilizing what is known as the “blood-alcohol:breath-alcohol partition ratio.” The standard partition ratio long used in California (and indeed, throughout the U.S. and most other countries) is legislatively set at 2,100 to one—meaning that the amount of alcohol in 2,100 milliliters of a breath sample is deemed to correspond to the amount of alcohol in one milliliter of blood. (McNeal, supra, 46 Cal.4th at pp. 1188, 1191, citing
This 2,100-to-one partition ratio (sometimes stated in terms of the amount of alcohol in 210 liters of breath and 100 milliliters of blood) is a scientifically agreed-upon construct arrived at by use of what the parties in their briefs refer to as “black box methodology“—in other words, performance studies that measure and correlate both an individual‘s blood sample and that same individual‘s simultaneously collected breath sample—as analyzed by a properly functioning breath-testing machine. (See Downie, supra, 569 A.2d at p. 248 [describing studies of “paired venous blood/breath samples“]; see also State v. Hanks (2001) 172 Vt. 93 [772 A.2d 1087, 1089] [“a conversion rate of 2100:1 [is] an assumed blood-breath ratio, which represents the relationship between the number of alcohol molecules in the bloodstream to the number present in the breath when both substances are tested simultaneously“]; see generally Mason & Dubowski, Breath-Alcohol Analysis, supra, 21 J. Forensic Sciences No. 1, at p. 16 et seq.)
It is well documented by scientists and accepted by courts that true partition ratios vary both between individuals and within individuals over time. This “partition ratio variability” is known to result from various physiological factors including breathing patterns (speed and depth of exhalation), body temperature, hematocrit level (ratio of red blood cells to total blood volume), sex, and each person‘s medical health. (See McNeal, supra, 46 Cal.4th at p. 1191 [listing, as variables affecting the actual ratio of an individual‘s breath-alcohol concentration to blood-alcohol concentration, ” ‘body temperature, atmospheric pressure, medical conditions, sex, . . . the precision of the measuring device,’ ” and “hematocrit level and elapsed time between drinking and breath-alcohol measurement” (italics added)]; People v. Lepine (1989) 215 Cal.App.3d 91, 94 [263 Cal.Rptr. 543] [listing, as additional factors, “the speed of exhalation, the depth of exhalation, the amount of humidity in the air, the amount of mucus in the lungs” (italics added)]; see generally Bransford, supra, 8 Cal.4th at p. 889; State v. Brayman (1988) 110 Wn.2d 183 [751 P.2d 294, 297] (Brayman); Downie, supra, 569 A.2d at pp. 246–248; Annot., supra, 90 A.L.R.4th at p. 160; Mason & Dubowski, Breath-Alcohol Analysis, supra, 21 J. Forensic Sciences at pp. 21-29.)
Because the 2,100-to-one standard was set by considering the results from numerous individuals in various performance correlation studies, the general
We recently reaffirmed the 2,100-to-one conversion ratio, noting that despite the recognized variability, “most scientists” continue to “agree that the . . . ratio roughly approximates or even underestimates the ratio of most people.” (McNeal, supra, 46 Cal.4th at p. 1192.)15 Similarly, nearly a decade after it decided Downie, the New Jersey Supreme Court recently ordered an evaluation by a special master who in turn heard updated expert opinion concerning this and related issues. Adopting its special master‘s findings, the New Jersey court in Chun, supra, 943 A.2d 114, concluded that the 2,100-to-one ratio remains scientifically valid, and that “[t]he percentage of individuals for whom there may be an overestimation by use of this ratio remains ‘extraordinarily small.’ ” (Id., at p. 139.) The New Jersey high court concluded: “[T]he overwhelming evidence demonstrates that use of this ratio tends to underestimate the actual [blood-alcohol concentration] in the vast
B. Relevant legislation and related case law18
Prior to amendments enacted in 1990,
1. Amendment of section 23152(b) in 1990 to define the offense alternatively in terms of alcohol concentration in blood or in breath
In response to this and similar litigation occurring nationwide concerning partition ratio variability, Drs. Mason and Dubowski, the authors of the 1976 article cited earlier—Breath-Alcohol Analysis, supra, 21 Journal of Forensic Sciences 9—described the scientific and legal problems triggered by undertaking such conversions and proposed that “[a]ll of these vexing matters [could be] avoided by the expedient of reporting only the quantity of ethanol found per unit volume of delivered breath . . . and defining the offense by statute in terms of the amount of ethanol allowable per unit volume of the sample analyzed.” (Id., at p. 32, italics added.) “Thus for breath, in a given jurisdiction, the quantity of ethanol present in 210 litres of substantially alveolar air (. . . 0.08 g/210 1 for states using the 0.08% [weight/volume] standard for blood), could define by statute the alcohol-related element of the offense of driving while under the influence of alcohol.” (Id., at p. 33.) The authors concluded: “We believe that the conversion of a breath quantity to a blood concentration of ethanol, for forensic purposes, should be abandoned and that the offense of driving while under the influence of alcohol should be statutorily defined in terms of the concentration of ethanol found in the breath in jurisdictions employing breath analysis.” (Ibid., italics added.)
In early 1990, Assembly Bill No. 4318 (1989–1990 Reg. Sess.) was introduced, proposing to revise
2. Construction of the amended statute in Bransford and McNeal
We construed the revised version of
Having determined that the amended statute alternatively “defined the substantive offense of driving with a specified concentration of alcohol in the body” (Bransford, supra, 8 Cal.4th at pp. 892–893, italics added), we also concluded that the amended statute rendered irrelevant consideration of matters such as partition ratio variability, because the revised statute “defined the offense without regard to such ratios.” (Id., at p. 893.) It followed, we held, that expert evidence concerning partition ratio variability was properly excluded in trials under the amended per se statute. (Ibid.)19
By contrast, as we subsequently observed in McNeal, supra, 46 Cal.4th 1183, the traditional generic offense set out in
III. Analysis
As noted earlier, the People assert that the appellate court erred both in overturning the trial court’s exclusion of the prehearing and proffered testimony of Dr. Hlastala, and also in finding the alleged errors to be prejudicial. Defendant, on the other hand, insists that neither Dr. Hlastala’s prehearing jury testimony nor the subsequent proposed testimony concerning reliability of breath-testing machines, constituted evidence of partition ratio variability, and that the trial court erred by concluding otherwise and precluding that testimony with regard to the per se
Second, defendant asserts, the trial court erred in barring Dr. Hlastala’s additional proposed testimony, adduced at the hearing outside the presence of the jury, that other physiological factors, such as pattern of breathing (speed and depth of inhalation and exhalation), body and breath temperature, and hematocrit level (ratio of red blood cells to total blood volume), make breath testing unreliable.
We will address these contentions in turn. Before doing so, however, we again note that defendant’s trial was conducted before our decision in McNeal, supra, 46 Cal.4th 1183 (discussed ante, pt. II.B.2.), in which we clarified that partition ratio variability evidence, although inadmissible with respect to a per se charge under
A. Testimony that breath-testing machines are unreliable because expired breath contains only alcohol that has been absorbed from the upper airways and hence the machines fail to sample and analyze the concentration of alcohol contained in alveolar, deep lung air
As observed ante, in part I.B.1., Dr. Hlastala testified before the jury that “little blood vessels . . . called ‘bronchial vessels’ . . . bring alcohol” to the mucus membranes lining the airway, and that “if we inhale and we pick
Defendant and amicus curiae on his behalf, the California DUI Lawyers Association, argue that this aspect of the excluded expert testimony did not constitute inadmissible partition ratio variability evidence under Bransford, supra, 8 Cal.4th 885, because in this part of his testimony Dr. Hlastala did not purport to compare breath-testing results with blood-testing results, but instead simply focused on the breath sample that was collected for analysis. In addition, they assert, the evidence was relevant and necessary to allow presentation, as a defense to the per se charge, of the argument that the specimens collected by breath-testing machines fail to comply with
The People respond by emphasizing the practical impossibility of sampling pure alveolar, deep lung air: “It would be too invasive to insert a tube into a
The People elaborate on their position by emphasizing that the underlying performance correlation studies (described ante, pt. II.A.3.) have always used simultaneous (1) blood samples and (2) “end-expiratory” breath samples as measured by properly functioning and calibrated breath-testing machines to verify the accuracy of breath-testing machine readings. The People conclude that “the laws and regulations governing drunk driving and breath alcohol testing do not require the alcohol in breath testing samples to be only from alcohol that originates from the blood vessels next to the alveoli, as opposed to alcohol that originates from the bronchial vessels (bronchial alcohol) and migrates down the airway and into the alveolar region during inhalation. The per se . . . charge of . . .
Defendant and the supporting amicus curiae, in turn, counter by asserting that defendant had a right to challenge the reliability of breath-testing machines generally, and that the People in essence propose to “ignore any problems with the failure of the breath test used in this case to comply with
As explained below, we agree with defendant that this aspect of the prehearing jury testimony was not the same as the type of testimony regarding partition ratio variability that was at issue in Bransford, supra, 8 Cal.4th 885, and McNeal, supra, 46 Cal.4th 1183. Nonetheless, we conclude that the expert testimony at issue here was properly excluded, insofar as the trial court’s ruling related to the statutory per se charge.
As noted earlier, we explained in Bransford, supra, 8 Cal.4th 885, that the 1990 amendment of the per se offense (
Although the prehearing jury testimony under discussion at this point did not purport to address the variability of partition ratios for different persons or at different times for the same individual, the testimony was nonetheless analogously and fundamentally at odds with the statutory per se offense, in that it suggested the results of breath-testing machines always are unreliable because they fail to measure the alcohol content of the air from the alveolar region of the lungs. That testimony failed to take into account that the standard 2,100-to-one partition ratio expressly incorporated in the per se statute was established by simultaneously measuring a subject’s blood-alcohol level and breath-alcohol level as disclosed by a properly working and calibrated breath-testing machine that samples the last part of the subject’s expired breath. Accordingly, whether or not that part of expired breath accurately reflects the alcohol that is present only in the alveolar region of the lungs, the statutorily proscribed amount of alcohol in expired breath corresponds to the statutorily proscribed amount of alcohol in blood, as established by the per se statute.
Applying standard principles of statutory construction to determine and effectuate legislative intent (e.g., People v. Pieters (1991) 52 Cal.3d 894, 898–899), we conclude that when the Legislature employed the word “breath” in
As noted earlier, defendant also observes that the Legislature, in
We also find it significant that for many decades it has been understood that the passage of breath through the airways does indeed influence the resulting sample and makes it “virtually impossible . . . to obtain” samples of air from the alveolar region that are “uncontaminated” by the exposure to mucus membranes lining the airways because “[t]he sample taken at the end of the expiration must necessarily pass through the bronchi and oral-pharyngeal cavities and in doing so may gain or lose gases to the gas-fluid interfaces of the mucus membranes.” (Spector, Alcohol Breath Tests: Gross Errors in Current Methods of Measuring Alveolar Gas Concentrations (Apr. 2, 1971) 172 Science 57, 59; see Dubowski, The Technology of Breath-Alcohol Analysis, supra, U.S. Dept. of Health & Human Services, pub. No. (ADM)92-1728, at p. 5 [“alveolar air is modified . . . by repeated reequilibration of the alcohol of the breath with that of the fluids lining the respiratory tract during expiration . . .”].)
These considerations demonstrate that when
Given this understanding of
Further, in the process of considering this evidentiary question, our independent research revealed other regulations and statutes, not addressed in the parties’ original briefs, that shed additional light on how the Legislature views the scheme of breath testing for alcohol concentration. These regulations and statutes confirm our interpretation of
1. Regulations amended in 1985: California Code of Regulations, title 17, sections 1221.2 and 1221.3
Through the 1970s, the State Department of Health Services, acting under then applicable legislative authorization (see
As amended in 1985, and as still in effect today,
Correspondingly, as amended in 1985, and still today,
The notice accompanying the State Department of Health Services’s emergency order explained: “The instruments on the [federal] list have passed laboratory evaluation by DOT [(the U.S. Dept. of Transportation)] against [that agency’s] performance specifications. . . . The use of these instruments will provide law enforcement agencies in the State a list of current, state-of-the-art approved breath testing instruments. [¶] The Department and DOT approval mechanisms for the breath testing instruments differ significantly only in the experimental test for establishing the correlation of the instruments’ breath test results with the actual alcohol concentrations in the blood of the human test subjects. The Department uses tests of human subjects for this determination while DOT uses a Breath Alcohol Sample Simulator (BASS). The BASS is a device designed by DOT to provide the appropriate breath sample by simulating the variables of a human expiration including pressure, temperature, and rate of delivery. The Advisory Committee on Alcohol Determination has determined that the instruments approved by either test are equivalent in terms of scientific validity.” (Cal. Reg. Notice Register 86, No. 1-Z (Jan. 3, 1986), A-32 [Informative Digest], italics added; see generally BASS for Qualification Testing of Breath Alcohol Measurement Devices, supra, at p. vii [noting that the BASS device is designed to “provide an objective, reproducible mechanical substitute for human subjects in the evaluation of the performance of the breath sample collecting systems of breath alcohol instruments”].)
2. Legislative action in 2004: Health and Safety Code section 100701
Nearly two decades after the State Department of Health Services adopted these emergency regulations, the Legislature enacted
As observed earlier, another statute,
In other words, for almost two decades before the Legislature enacted
3. The effect of these regulations and statutes
We asked the parties to submit supplemental briefs concerning the effect, if any, of these statutes and related regulations. Defendant concludes that although the People may be expected to argue otherwise, these statutes and regulations do not support an assertion that the trial court properly excluded the challenged testimony insofar as it related to the statutory per se charge.25 Rather more surprisingly, the People—represented by the City Attorney of San Diego—do not argue otherwise. They assert that these statutes and regulations merely have the “combined effect of ensuring the accurate testing of deep lung, or alveolar, air.”26 As explained below, we disagree with both parties.
It is apparent that the models of breath-testing machines employed here—and scores of others—have been subject to rigorous review and have been found by the federal agency to reliably measure the alcohol content of alveolar, deep lung breath samples. (See generally 58 Fed. Reg. 48705, 48706–48707 [“Model Specifications”—procedures for submitting machines for testing], 48707–48708 [“Model Specifications”—definitions and eight specific tests].)27 As observed above, no machine model can meet federal standards unless it “measure[s] the alcohol content of deep lung breath samples with sufficient accuracy for evidential purposes.” (58 Fed.Reg. 48705, 48707, italics added.) The circumstance that both machine models used in this case have been certified for evidential use (see ante, fn. 24) reflects that they have been found by the National Highway Traffic Safety Administration of the United States Department of Transportation to reliably sample and measure alveolar, deep lung breath as contemplated by both federal and California regulations.
Even more significantly, it also is apparent that the State of California has enacted a policy of adopting, incorporating, and deferring to federal specifications for, and certification of, models of breath-testing machines. By both statute and legislatively endorsed regulations, California has in essence determined that all models meeting the federal standards produce sufficiently reliable results for purposes of California’s statutes relating to alcohol-concentration limits. To the extent Dr. Hlastala’s testimony would have informed the jury that the breath-testing machines employed in this case, and
Although Dr. Hlastala may hold scientifically based reservations concerning these legislative conclusions, we must defer to and honor the Legislature’s reasonable determinations made in the course of its efforts to protect the safety and welfare of the public. As our Court of Appeal has observed, “The fact that the current state of scientific knowledge has not settled the ongoing scientific debate as to the best method of measuring inebriation does not preclude the Legislature from regulating driving based on conflicting scientific theories.” (People v. Ireland (1995) 33 Cal.App.4th 680, 693.) Likewise, as the Washington Supreme Court observed in analogous circumstances: When “scientific opinions conflict on a particular point, the Legislature is free to adopt the opinion it chooses, and the court will not substitute its judgment for that of the Legislature.” (Brayman, supra, 751 P.2d at p. 300; see Downie, supra, 569 A.2d at p. 251 [concluding that “[t]he reliability of [breath-testing machine testing] results will continue to be the subject of judicial notice . . .” and that testimony concerning partition ratio variability by expert witnesses “will . . . continue to be inadmissible” in prosecutions under a “per se” statute].)
As the trial court observed, defendant remained free to argue, and present evidence, that the particular machines used in this case malfunctioned, or that they were improperly calibrated or employed. But the fundamental reliability of the breath-testing machine models used in this case to produce results that are pertinent to the per se statute has been determined by the Legislature. That legislative determination is not subject to rebuttal as a defense in a criminal prosecution. It is hornbook law that a “court’s authority to second-guess the legislative determinations of a legislative body is extremely limited. It is a ‘well-settled principle that the legislative branch is entitled to deference from the courts because of the constitutional separation of powers.’ ” (Connecticut Indemnity Co. v. Superior Court (2000) 23 Cal.4th 807, 814; see, e.g., Minnesota v. Clover Leaf Creamery Co. (1981) 449 U.S. 456, 469 [deferring
For these reasons we conclude that defendant’s regulation-based argument in support of admitting the challenged expert evidence rests on an incorrect understanding and interpretation of the legislatively endorsed regulations in question. It follows that under both the statute (
B. Proposed testimony that breath-testing machines are unreliable because other physiological factors may affect the transmission of alcohol from the bloodstream to the deep portions of the lungs and then through the exhalation process
As noted earlier, defendant also sought to have Dr. Hlastala testify that a series of other physiological factors—individual breathing patterns (speed and depth of exhalation), body and breath temperature, sex, and hematocrit level
Although many other jurisdictions employ these and similar breath-testing machines, defendant cites only one decision from another jurisdiction appearing to allow testimony like that offered here—challenging, on the basis of the listed physiological factors, the reliability of approved devices that have been properly maintained and operated. (State v. Cooperman (Ct.App. 2012) 230 Ariz. 245 [282 P.3d 446] (Cooperman) [affd., without addressing this issue, in State v. Cooperman (2013) 306 P.3d 4].)
As explained below, we do not find this authority persuasive with regard to the evidentiary question under California law. (See post, fns. 30 & 31.) Instead, we agree with the trial court that this aspect of the expert testimony would essentially constitute partition ratio variability evidence, which, as noted, is barred in
As the Court of Appeal below emphasized, and as defendant stressed in his briefs and at oral argument, Dr. Hlastala expressly disclaimed that his testimony implicated the concept of partition ratio variability, because, he said, he was not questioning the conversion of breath-alcohol levels into blood-alcohol levels. Instead, he asserted, he was considering factors that influence the composition of the breath sample that the machines collect. In other parts of Dr. Hlastala’s proposed testimony, however, he did make repeated references to comparing breath tests to blood tests—maintaining that (1) breath testing is inferior because it is based on the assumption that the measured breath “is directly related to water in the lungs, which is directly related to what’s in the blood” and (2) as between testing of venous blood and breath testing, the former was “the standard,” and superior.29 The evident import of these aspects of his proposed testimony was that breath testing is suspect in comparison with venous blood testing, and that in order to be scientifically reliable, a breath test result should not be considered on its own, but only in relation to the known result of a blood test. In this sense, Dr. Hlastala’s proposed testimony would indeed have invited the jury to draw unfavorable comparisons between the two modes of testing that the Legislature has, by
The People correctly note that defendant—the proponent of the evidence—had the burden to produce preliminary facts to support his view that this aspect of Dr. Hlastala’s proposed testimony did not constitute partition ratio variability evidence. Dr. Hlastala’s observation that there exists variation in the alcohol concentration of any given breath sample is, in essence, substantively similar to observing that there is variation in partition ratios among persons and indeed in a single person—testimony that is inadmissible as irrelevant in a
In any event, the reasons we have discussed ante, in part III.A., also clearly support a conclusion that the trial court properly excluded the challenged testimony. To the extent that Dr. Hlastala’s testimony would have informed the jury that all results from breath-testing machines are unreliable because of the listed physiological factors, the proposed testimony sought to nullify determinations necessarily made by the federal agency and endorsed by our Legislature in 2004, when, presumably aware of the science and decisions reporting that breath samples are affected by these same and related factors (see ante, pt. II.A.3.), the Legislature nevertheless implicitly endorsed the State Department of Health Services’s 1985 determination that any machine model that meets the federal agency’s specifications and is listed as conforming is reliable and approved for evidential use in a California prosecution. As noted earlier, just as that legislative determination is not subject to nullification by courts, nor is it subject to nullification by a jury at the invitation of an expert witness in a criminal prosecution of a statutory per se charge.31
IV. Conclusion and disposition
The trial court did not err in limiting Dr. Hlastala’s prehearing jury testimony and excluding his subsequently proposed elaborating testimony with respect to the statutory per se charge. As the trial court observed, defendant remained free to argue, and present evidence, that the particular machines used in this case malfunctioned, or that they were improperly calibrated or employed. But as explained earlier, the 0.08 percent breath-alcohol concentration formulated by the Legislature in enacting the underlying per se offense,
In light of these conclusions and the corresponding regulations and statutes discussed earlier, the fundamental reliability of federally approved, properly calibrated and employed breath-testing machines used in the application and enforcement of the per se statute is a matter that has been determined as policy by the Legislature—and a defendant’s expert witness may not invite a jury to nullify that determination in the manner at issue here. Accordingly, the judgment of the Court of Appeal is reversed.
Kennard, J., Baxter, J., Werdegar, J., Chin, J., Corrigan, J., and Liu, J., concurred.
Notes
The amended complaint also charged one count of driving in excess of 100 miles per hour (
Still other state regulations simply provide that a breath sample must meet the requirements of an approved breath-testing machine. (See, e.g., 13 Alaska Admin. Code, § 63.040 [“satisfactory sample” is obtained when the machine‘s “visual display” so indicates]; Fla. Admin. Code R. 11D-8.002(12) [“samples of breath . . . using an approved breath test instrument“]; Md. Code Regs. 10.35.02.02.B.(5) [” ‘Breath sample’ means the amount of breath delivered by the individual being tested that is an adequate volume to be analyzed by the breath testing instrument.“].)