DUI Law
I
n Arizona, the shift from the standard set forth in Frye v. United States, 293 F. 1013 (D.C. Cir. 1923),
to that in Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993), has had profound effects
on almost every type of law in which both parties enter a courtroom. The change appears to be a
nuanced difference in the standards necessary to introduce scientific evidence to the trier of fact, but the
practical ramifications have been significant.
This has been particularly true in the field of Arizona DUI defense. As one can imagine, the introduction
of scientific evidence in a DUI trial has a substantial effect on the results of said trial. Evidence in a DUI
trial can be broken up into three basic categories: (1) the observations of the arresting officer, which
are not scientific in nature; (2) the results and interpretation of the roadside testing, which are clearly
scientific in nature; and, (3) the results of any chemical tests that were taken, namely the blood or breath
How DUIs in
Arizona Are
Being Shaped
By Daubert
By Craig Rosenstein
tests. This article will focus on the latter two categories.
Most people are unfamiliar with the scientific literature behind the interpretation of the roadside
testing (which typically entails the eye and balancing tests). What makes these tests susceptible to
Daubert challenges are the lack of peer-reviewed scientific materials that substantiate the claims made
about their efficacy. The same level of scrutiny regarding the underlying science was not previously
applied when Arizona used the Frye standard. These roadside tests were created in their current form
when the National Highway Traffic Safety Administration (NHTSA) contracted with a private company
in Southern California to validate and standardiz e roadside testing. A series of experiments were done to
determine the accuracy of these tests. What makes these experiments susceptible to a Daubert challenge
is the methodology (or lack thereof) in the testing process. In fact, some of the experiments performed
had the police officers grading themselves without supervision, and reporting their results to the people
conducting the experiments. This falls so far below the standards generally accepted in the gathering of
evidence that any scientific claims made from those results are almost meaningless. In the case of United
States v. Horn, 185 F. Supp. 2d 530 (D. Md. 2002), the entire battery of roadside tests was successfully
challenged in Maryland. In a more than 70-page opinion, mostly critical of the scientific data supporting
the roadside test battery, the court limited the officers from testifying about the meaning of the tests, and
limited it to purely their observations. For example, the officers are now limited to testify that a person
put their foot down when asked to balance on one leg, but not that it correlates to a percentage chance
that the person had a BAC above the legal limit as they had previously done, and still do in Arizona.
The chemical tests, namely the blood or breath tests, have similarly been challenged in Arizona and
across the country recently under Daubert. August saw two major successful challenges. In Arizona, a
group of attorneys won a Daubert hearing in Maricopa Superior Court concerning the blood results
Craig J. Rosenstein represents clients in
many aspects of criminal law, including
misdemeanor and felony cases, with a focus
on driving under the influence (DUI) defense.
He graduated from the University of Arizona
in Tucson, Arizona where he received his
Bachelor of Arts degree in political science and
then attended Arizona State University where
he received his Juris Doctor (J.D.) degree. He
has been credentialed by the National College
of DUI Defense. He is licensed to practice
law in Arizona, as well as in the U.S. Federal
District Court in the District of Arizona. He can
be reached by phone at (480) 946-0681 or
(480) 248-7666 or by email at crosenstein@
attorneyatlawmagazine.com.
of DUI defendants charged with felony DUI. The court in that case criticized the Scottsdale crime lab’s
knowledge of faulty equipment being used and the mechanisms they failed to implement to correct said
problems. The court determined that its obligation as a gatekeeper under Rule 702 of the Arizona Rules
of Evidence precluded the admission of those results.
Similarly, there was a Daubert challenge to the Intoxilyzer 8000 evidentiary breath testing device
in Ohio in August. In August, the machine was determined to be scientifically unreliable to such
an extent that the court, as a gatekeeper, precluded its admission. This ruling is being examined
closely in Arizona because the Intoxilyzer 8000 is the only breath testing machine whose results are
admissible in Arizona courts.
As one can see, Arizona’s recent switch to Daubert is having a significant effect on the admission of
scientific evidence in court. In DUI prosecutions, this switch is calling into question the ability for the
state to introduce evidence that had previously been used.