Womack, J., delivered the opinion for a unanimous Court.

Does a trial court err by admitting into evidence the results of an Intoxilyzer test without first considering at a “gatekeeper” hearing the validity of the underlying scientific theory of, and the technique of its application by, Intoxilyzers? We hold that it does not.

This question arose in a prosecution for driving while intoxicated. Coppell Police Officer Stephen Burres arrested the appellant for this offense on January 23, 1997, and he administered the Intoxilyzer test that is at issue in this appeal.

Burres was the State’s first witness. The State did not use Burres to sponsor the results of the Intoxilyzer test, but the attorneys on both sides vigorously questioned him regarding his administration of the test.

The State’s next witness was Dallas County Technical Supervisor Ron Oliver. Before questioning Oliver, the appellant’s attorney urged his pre-trial motion to suppress Intoxilyzer results, which was “based on several rules of the Rules of Criminal Evidence, including 401, 402, 403, 702, and 705, and also on the basis that there was non- compliance with the requirements of the DPS rules about which—about that aspect of which I would like to question Mr. Oliver.”

The appellant’s attorney took Oliver on voir dire outside the jury’s presence.

Just before the court ordered the jury back in, the appellant’s attorney again objected to the admission into evidence of the Intoxilyzer results (as distinguished from testimony interpreting or extrapolating from the results). The trial court overruled these objections.¹

The State, by Oliver’s testimony, laid the foundation for admission of the test results under the business-records exception to the hearsay rule. Only then did the State offer into evidence the printout from the Intoxilyzer.

The appellant’s attorney objected on the grounds that the State had not satisfied the requirements of the business-records exception and urged, for the last time, his objection based on Rules of Evidence 702, 401, 402, 403, and 705. The Court overruled the objections and admitted the breath-test results into evidence. The results showed that the appellant’s blood-alcohol concentration was 0.124 on the first test and 0.121 on the second test.

The jury convicted the appellant of driving while intoxicated and he filed a notice of appeal.

Before the court of appeals, the appellant argued that the trial court failed to perform its “gatekeeper function” in connection with the expert testimony about the Intoxilyzer test. The court of appeals overruled this argument on the ground that the testimony by the arresting officer, together with the testimony of Mr. Oliver, sufficed to prove that the Intoxilyzer results were admissible. The court also cited Transportation Code section 724.064 as support for the proposition that the State does not have to prove that the Intoxilyzer test is scientifically reliable before the results are admissible. The Court did not address Rule of Evidence 702 or our decisions construing the rule.²

In his brief submitted to this Court, the appellant argues that the trial court erred by admitting into evidence the results of an Intoxilyzer test without first holding a gatekeeper hearing.

The State argues that the admission of scientific evidence in DWI cases is controlled not by Rule of Evidence 702 and our cases interpreting that rule, but by the Transportation Code. Thus, the State claims, our decisions about Rule 702 have “no applicability to a DWI case.”

We do not agree entirely with either party’s argument. Rule of Evidence 702 does apply to evidence of breath-test results; there are issues of admissibility for the trial court under the Rules of Evidence, but the issues are affected by the Transportation Code. The trial court and the court of appeals did not err in holding that the appellant’s objections in this case were without merit.

In Kelly v. State,³ we addressed the question whether the “general-acceptance test” that was articulated in Frye v. United States,⁴ governed the admissibility of scientific evidence in Texas courts. At issue in Kelly was the admissibility in a murder trial of certain expert testimony regarding DNA evidence.⁵ We observed that Rule of Evidence 702 governs the admission of all expert testimony, and we set out the text of that Rule:

If 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.

We decided that a scientific theory’s acceptance in the scientific community was relevant to, but not dispositive of, the issue of its admissibility under Rule 702.⁶ Having found the Frye test to be insufficient, we articulated a new test: a trial judge must determine whether scientific evidence is sufficiently relevant and reliable to help the jury in reaching an accurate result.⁷ To be considered reliable, we held, evidence from a scientific theory must satisfy three criteria: (1) the underlying scientific theory must be valid; (2) the technique applying the theory must be valid; and (3) the technique must have been properly applied on the occasion in question.⁸ We further held that the proponent of the evidence must establish its reliability by clear and convincing evidence in a preliminary hearing held outside the presence of the jury⁹ — the “gatekeeper hearing” to which the appellant refers. In Hartman v. State, we held that the Kelly test applied to all scientific evidence, whether the science was novel or otherwise.¹⁰

The appellant relies on Hartman as controlling authority. As he points out, the scientific evidence at issue in Hartman was expert testimony relating to the results of an Intoxilyzer test.¹¹

Hartman was correctly decided, but it will not resolve this case. The testimony that we considered in Hartman was different from the evidence that is at issue in the case now before us, and we did not reach the question that is before us today.

Hartman moved to suppress the results of the Intoxilyzer test. On the basis that it pertained to scientific techniques which were not shown to be reliable or relevant, he objected to the admissibility of testimony by: (1) Officer John Muzny, who arrested Hartman and administered the Intoxilyzer test; and (2) George McDougall, Bexar County’s Breath Test Technical Supervisor.¹²

At the hearing on the appellant’s motion, only McDougall, the technical supervisor, testified. McDougall testified that at the time of the test, Hartman’s blood- alcohol content (BAC) was 0.138. From this, he extrapolated that Hartman’s BAC was between 0.110 and 0.15 or 0.16 at the time of the stop. He testified that he was able to state Hartman’s BAC range at the time of the stop because of his training in studying the effects of alcohol upon a person’s ability to safely drive a car, his study of how much alcohol it takes to reach a given BAC based on body weight, and his observations of over 2000 students going through a complete drinking cycle. On cross-examination, McDougall testified to the standard elimination rate of alcohol and to how food affects the equation. The trial judge denied the appellant’s motion.¹³

On appeal, the appellant argued that the State had failed to make the Rule 702 showing for admissibility of scientific expert testimony as required by Kelly.¹⁴ The court of appeals quoted a portion of Hartman’s argument at the pre-trial hearing:

We don’t believe that they are entitled to bring him in to testify concerning the results of that Intoxilyzer to try and show that my client was intoxicated while he was driving the motor vehicle because as Mr. McDougal [sic] will testify, he cannot relate back to the time of driving from the time of the test. He will tell this Court that this test shows what that individual’s breath alcohol content was at the time he took the test and he can give an expert opinion on that, but what I want to show the Court is that he cannot give this court an expert opinion as to what the man’s breath test score was at the time he was driving and as a consequence, it’s not admissible.¹⁵

As the italicized portion of the argument makes clear, Hartman conceded that McDougall could testify as to the results of the breath test. He took issue only with McDougall’s extrapolation testimony. His only argument that the results themselves were inadmissible was that they were irrelevant to show the subject’s BAC at the time of the stop unless the State offers extrapolation testimony — an argument that we have never accepted and that other courts have rejected.¹⁶

The court of appeals overruled Hartman’s argument on the ground that the Kelly test applied only to novel scientific evidence.¹⁷ The court said that the Intoxilyzer test is not novel. “Rather, we are here confronted by an Intoxilyzer test that is rendered admissible by statute, Tex. Rev. Civ. Stat. Ann. art. 67011-5, §3(a) (Vernon Supp. 1995) [now codified as Section 724.064 of the Transportation Code], and that has long been admissible without any predicate showing as to reliability, see Slagle v. State, 570 S.W.2d 916 (Tex. Cr. App. 1978).”¹⁸ The court of appeals held that the trial court did not abuse its discretion by admitting McDougall’s extrapolation testimony because it was not novel scientific evidence and it satisfied the “general criteria” of Rule 702.¹⁹

“We granted [Hartman’s] petition for discretionary review to determine whether the admissibility criteria for scientific evidence announced in Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993), and Kelly v. State, 824 S.W.2d 568 (Tex. Cr. App. 1992), apply to all ‘scientific evidence.’”²⁰ Our answer was, yes. We had granted review of other questions, but, due to the disposition of the first question, we did not reach the others.²¹

Our opinion in Hartman mentions only McDougall’s extrapolation testimony and the court of appeals’ conclusion that “the admissibility of [such] testimony should be examined in line with the more general criteria of Rule 702.”²² Observing that “[n]owhere in Kelly did we limit the two-pronged standard to novel scientific evidence,”²³ we held that the Kelly test applied to all scientific evidence offered under Rule 702. We did not address the court of appeals’ statement that the results of the Intoxilyzer test were “rendered admissible by statute.”²⁴

We adhere to the decision in Hartman that Kelly applies to all scientific evidence offered under Rule 702. This case requires us to address another, more specific question:

whether, in applying Rule 702, courts must accept a legislative determination of reliability.

In 1950, we held that it was not error, in the trial of T.G. McKay, to admit evidence of a breath test for alcohol when a research biochemist in the University of Texas testified that he thought the test was reliable.²⁵ We observed that several national organizations had recommended the passage of laws that recognized the value of chemical analyses of breath and other bodily substances, and that gave rise to presumptions of a person’s being (or not being) under the influence of intoxicating liquor. We said, however, “The Legislature of Texas may pass such law, if within its constitutional powers, but the courts of Texas have no legislative duties or powers.”²⁶

The Sixty-first Legislature used its authority in 1969, enacting a statute that made admissible evidence of chemical tests of breath for alcohol in trial in which driving while intoxicated was an issue, if the analysis was performed in accordance with regulations of the Department of Public Safety.²⁷ These provisions, as amended, are now codified in the Transportation Code.

Section 724.064 of the Transportation Code makes admissible, in the trial of certain intoxication and alcoholic beverage offenses, evidence of alcohol as shown by tests of breath specimens:

On the trial of a criminal proceeding arising out of an offense under Chapter 49, Penal Code, involving the operation of a motor vehicle or watercraft, or an offense under Section 106.041, Alcoholic Beverage Code, evidence of the alcohol concentration or presence of a controlled substance, drug, dangerous drug, or other substance as shown by analysis of a specimen of the person’s blood, breath, or urine or any other bodily substance taken at the request or order of a peace officer is admissible.

Section 724.016 of the Transportation Code provides for administrative regulation of the taking and testing of breath specimens:

(a) A breath specimen taken at the request or order of a peace officer must be taken and analyzed under rules of the department by an individual possessing a certificate issued by the department certifying that the individual is qualified to perform the analysis.

(b) The department may:

(1) adopt rules approving satisfactory analytical methods; and
(2) ascertain the qualifications of an individual to perform the analysis.

(c) The department may revoke a certificate for cause.

The “department” to which the statute refers is the Department of Public Safety.²⁸ The Department’s “Breath Alcohol Testing Regulations” appear in Title 37, Chapter 19 of the Administrative Code.

These sections of the Transportation Code are not the only legislation that authorizes the admission of scientific evidence in the courts of this state. The Family Code makes admissible the report of a genetic-testing expert in proceedings to adjudicate parentage.²⁹ This decision also was within the legislative authority.³⁰

Since our decision in McKay and the enactment of the 1969 statute, this Court has acquired some of the legislature’s duties and powers in the law of evidence. In 1985 the Constitution was amended to authorize the legislature to delegate to this Court the power to promulgate such rules as may be prescribed by law or the Constitution, subject to such limitations and procedures as may be provided by law.³¹ In the same year the legislature delegated to this Court the power to promulgate rules of evidence in the trial of criminal cases.³²

That act of the legislature authorized this Court to designate for repeal 56 specific, evidentiary statutes if the Court promulgated and filed a comprehensive body of rules.³³ The statutes for admissibility of breath-test results were not among those for which repeal was authorized in 1985. Since then, the legislature has amended or reenacted the admissibility statute three times.³⁴ This leaves us with no doubt that the legislature’s decision, about breath-test results in these kinds of cases, is still in effect.

When courts decide questions of the law of evidence in criminal proceedings, the scheme of “hierarchical governance” is that civil statutes govern before the Rules of Evidence and the common law.³⁵ Where possible, courts are to remove inconsistency by reasonable construction.³⁶ In this case, any inconsistency between the Transportation Code and Rule of Evidence 702 may be removed by construction rather easily when the statute is seen in terms of legislative decisions as to the reliability of evidence.³⁷

Section 724.064 of the Transportation Code makes admissible, in the trial of certain intoxication and alcoholic beverage offenses, evidence of alcohol concentration as shown by analysis of breath specimens taken at the request or order of a peace officer. Section 724.016 authorizes the Department of Public Safety to “adopt rules approving satisfactory analytical methods.” The same section requires that breath specimens be taken and analyzed by individuals who are certified by the department.

Rule of Evidence 702 authorizes the testimony of experts, in the form of opinion or otherwise, when scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue.

The trial court’s task in assessing admissibility [of scientific expert testimony] under Rule 702 “is to determine whether scientific evidence is sufficiently reliable and relevant to help the jury in reaching accurate results.” To be considered reliable, evidence based on a scientific theory must meet three criteria: (1) the underlying scientific theory must be valid; (2) the technique applying the theory must be valid; and (3) the technique must have been properly applied on the occasion in question.³⁸

Harmonizing the Transportation Code and Rule 702, we hold that, when evidence of alcohol concentration as shown by the results of analysis of breath specimens taken at the request or order of a peace officer is offered in the trial of a DWI offense, (1) the underlying scientific theory has been determined by the legislature to be valid; (2) the technique applying the theory has been determined by the legislature to be valid when the specimen was taken and analyzed by individuals who were certified by, and were using the methods approved by the rules of, the Department of Public Safety; and (3) the trial court must determine whether the technique was properly applied, in accordance with the department’s rules, on the occasion in question.

In such cases there will be a “gatekeeper” hearing under Rule 702, as we held in Kelly and Hartman, but the issues at hearing will be only those that have not been resolved by the legislature’s decisions on reliability. If the technique was properly applied, the evidence of the result of the analysis is reliable under Rule 702. (Of course, admissibility of the evidence also depends on other factors of relevance and the counterweights in Rule 403.³⁹ Other rules or laws also may apply.)

This holding is in accord with our previous decisions. In 1978, we held that, because of the statute that is now codified in Section 724.064, the State need not establish as part of its predicate that the Breathalyzer examination is a scientifically reliable test before the results are introduced.⁴⁰ In a footnote, we said that the proponent’s predicate includes a showing that: “(1) properly compounded chemicals were used in the test, (2) there has been periodic supervision over the machine and the machine was operated by an individual who understands its scientific theory, and (3) the results of the Breathalyzer test are testified to by one qualified to translate and interpret those results in order to eliminate hearsay testimony.”⁴¹

When we addressed the results of an Intoxilyzer test in 1986, we modified the predicate to take into account the fact that the Intoxilyzer does not use chemicals. Because the Intoxilyzer “checks” itself through the use of a reference sample, we said that a showing of proper use of a reference sample satisfies the first prong of the predicate, as modified due to the nature of the instrument.⁴²

In 1995, after our decision in Kelly, we said that the statutes recognize the scientific reliability of breath tests when they are performed in accordance with the departmental regulations.⁴³

To be clear, we do not here decide that all evidence relating to Intoxilyzer results may be admitted by this shortened gatekeeper hearing. For example, the statutes do not address the reliability of the techniques for interpreting and extrapolating Intoxilyzer results. Therefore, expert testimony that grounds itself in such techniques is still subject to the requirement that the proponent establish, in a gatekeeper hearing, the reliability of the underlying scientific theory and the technique of its application, as well as the proper application of the technique on the particular occasion.⁴⁴

The trial court heard the testimony of Officer Burres and Technical Supervisor Oliver, after which the appellant’s objections were two: that Burres had not properly observed the appellant for 15 minutes before administering the test, and that the court had not conducted the gatekeeper hearing that the law requires.⁴⁵ We have held that the issue for a gatekeeper hearing in a case such as this is the proper application of the technique on this occasion.

On direct examination, Officer Burres testified that the reference sample, along with a practice test, is used to indicate to the operator whether or not the machine is working accurately. In response to the State’s questioning, Burres testified that he runs the practice test before each test he conducts and stated that “if the instrument is out of sync or is out of agreement, it will shut itself down and not allow itself to continue . . . It will print out on the card, “No .02 agreement,” which is a plus or minus .02, if the reference sample is out of tolerance.” Burres testified that nothing unusual happened during the appellant’s breath test. He gave the serial number of the machine used to obtain the appellant’s breath sample, and he opined that it was functioning properly when he administered the test to the appellant.

Mr. Oliver testified that the Intoxilyzer 5000, serial number 68-001909—which issued the breath test results at issue— had been certified by the Scientific Director of the Texas Department of Public Safety before the date of the appellant’s offense. He then testified to his own periodic maintenance of the machine. There are two kinds of inspections: the on-site inspection, which involves a physical testing of the machine, and a computer-modem inspection, whereby the technical supervisor calls the instrument by a modem connection and directs it to analyze the simulator solution, test it, and report back down the phone line. According to Oliver’s testimony, the most recent on-site inspection occurred on January 3, 1997, while the most recent computer-modem inspection took place on the date of the appellant’s breath test. Oliver stated that the instrument was operating correctly and capable of giving the correct results at the time of the appellant’s breath test.

The State questioned Oliver regarding his education and training. Oliver testified that he held a degree in biology with a minor in chemistry, graduate credit in the study of toxicology, and had completed a breath-test-operator training course and a technical supervisor course, a course of instruction on the Intoxilyzer 5000 and was certified as a technical supervisor in the Breath Alcohol Testing Program. Furthermore, Oliver’s responsibilities as a technical supervisor included maintenance of the Intoxilyzer 5000 that issued the appellant’s results. Oliver was the witness who sponsored the Intoxilyzer test results at the appellant’s trial.

The court of appeals held, “The testimony by the arresting officer, together with the testimony of Ronald D. Oliver, a technical supervisor in the Dallas County Medical Examiner’s Office, is sufficient to prove that the Intoxilyzer test results were admissible.”⁴⁶ Insofar as the appellant’s claim was that the law required a broader gatekeeper hearing, the court of appeals was correct to reject it.

As to the appellant’s only specific objection to the application of the technique of analysis, the court of appeals reviewed the evidence and held, “There is no showing of any violation of the Department of Public Safety regulation requiring the 15-minute observation period.”⁴⁷ This was the only issue that was raised at the gatekeeper hearing, and the record supports the court of appeals’ holding.

The judgment of the court of appeals is affirmed.

En Banc
Delivered September 25, 2002.
Publish.
¹

COUNSEL: I have a request too, as a matter of fact. The record will reflect, No. 1, Your Honor, based on the testimony that I know the Court recalls, given by Mr. Burres about his lack of and failure to monitor the defendant during the 15-minute observation period for belches, burps and regurgitation and the testimony given by Mr. Oliver about how a failure to do that would be unreasonable, we believe that the evidence supports the conclusion that the rules and regulations of the Department of Public Safety were not honored by Mr. Burres and, therefore, that the test results should not be admitted, consistent with Mr. Oliver’s testimony that the test was not performed in a reasonable manner, consistent with those rules. That’s our first objection. Does the Court care to rule on that one?

THE COURT: Let me hear the second one.

COUNSEL: The second one is, at this point in time I have not heard anything that satisfies the gate keeper requirements, so we still object to the admission of the results of any test performed by the Intoxilyzer 5000.

THE COURT: I’m going to deny both objections.

COUNSEL: So the record is clear or specific, the Court has denied the Motion to Suppress the Intoxilyzer test results that we filed prior to trial, correct? I just wanted to be sure that I’m being specific in terms of my objections.

THE COURT: Yes, sir.

COUNSEL: By way of supplementation of that, I want to be sure that the Court understands that we are objecting to the admission of the results of an Intoxilyzer test, under Rule 702 of the Rules of Criminal Evidence, and on the grounds that under Kelly and under Da[u]bert there has been insufficient showing; in fact, there’s been no showing by the State as to the scientific reliability of the test that’s being offered here.

THE COURT: I do understand your objections and I think you have stated your grounds, therefore, I’m overruling them. [Emphasis added throughout.]