State v. Jane H. Chun, et al. (A-96-06)
Argued April 5, 2007
Re-argued January 7, 2008 –- Decided March 17, 2008
HOENS, J., writing for the Court.
In this case, the Court addresses the scientific reliability of the Alcotest 7110 MKIII-C evidentiary breath-
testing device (Alcotest) and considers the admissibility of the Alcohol Influence Reports (AIRs) that it generates
for the prosecution of defendants under New Jersey drunk driving laws.
Defendants are twenty individuals charged with driving while intoxicated, N.J.S.A. 39:4-50, in Middlesex
County, who challenged the admissibility of Alcotest results in their individual proceedings. The Law Division
consolidated the cases to consider the reliability of the device. The State filed a motion requesting that the device be
recognized as scientifically reliable. The Law Division denied that motion, and the State filed an interlocutory
appeal. The Appellate Division remanded the matter, but before that proceeding could continue, the Court directly
certified the appeal pursuant to Rule 2:12-1 on December 14, 2005.
The Court remanded the case to retired Appellate Division Judge Michael Patrick King, sitting as a Special
Master, to conduct a hearing on the overall scientific reliability of the Alcotest. Following four months of
testimony, the Special Master issued a report on February 13, 2007. He concluded that the device was scientifically
reliable, conditioned on specific modifications and recommendations. After that report was issued, but before oral
arguments were heard, the manufacturer of the device, Draeger Safety Diagnostics (Draeger), moved for leave to
intervene, which motion the Court granted on March 27, 2007. Following oral arguments, the Court again remanded
the matter to the Special Master, this time to afford defendants an opportunity, following Draeger’s intervention, to
examine the source code that comprises the Alcotest software. After receipt of experts’ reports and further
testimony, the Special Master issued a supplemental report on November 8, 2007, in which he affirmed his original
finding of scientific reliability, contingent on several additional recommendations. Thereafter, the Court conducted
a second round of oral arguments.
Three distinct sets of challenges were raised regarding the use of Alcotest results in drunk driving
prosecutions. The first set of challenges related to how the machine measures a suspect’s blood alcohol
concentration (BAC). It was contested whether: (1) the Alcotest’s use of a 2100 to 1 blood/breath ratio is unreliable
because it overestimates the actual BAC of some individuals; (2) to avoid equal protection issues, all suspects,
instead of just women over the age of sixty, should be held to a minimum breath sample volume requirement of 1.2
liters of air; (3) a breath temperature sensor is necessary because the machine may overestimate the BAC of exhaled
breath above a certain temperature; (4) the machine’s tolerance, which is the deviation range within which test
measurements must fall to constitute a reliable result, is acceptable.
The next set of challenges related to the Alcotest’s programming and source code. Defendants argued that:
(1) the use of an algorithm to compensate for the depletion or “drift” of fuel cells artificially inflates results; (2) the
use of a “weighted averaging” algorithm, which places greater weight on later breath measurements than earlier
ones, also serves to artificially inflate results; (3) a buffer overflow error undermines the reliability of Alcotest
results in certain circumstances; (4) the lack of catastrophic error detection within the device undermines the
reliability of its results; and (5) the overall programming style fails to follow any design standard, and is so flawed
that it can not be relied on to produce accurate results.
The third set of challenges related to the admissibility of Alcotest results and foundational documents as
potentially violating Sixth Amendment rights under Crawford v. Washington.
Page 2
2
HELD: The Court adopts, as modified, the Special Master’s reports and recommendations. Subject to certain
conditions, the Court holds that the Alcotest is scientifically reliable and that its results are admissible in drunk
driving prosecutions. The Court contemporaneously issues an Order vacating its January 10, 2006, stay of drunk
driving prosecutions, appeals, and sentencing, which shall proceed in accordance with the directives set forth
therein.
1.
There is sufficient credible evidence to support the continued use of a 2100 to 1 blood/breath alcohol ratio
to estimate BAC from a breath sample. The overwhelming evidence demonstrates that use of this ratio tends to
underestimate the actual BAC in the vast majority of persons whose breath is tested. Although there may be a small
number of individuals who are disadvantaged by a device that uses the 2100 to 1 blood/breath ratio, there is sound
scientific support for its continued utilization. (pp. 49-52)
2.
The four criteria used by the device to identify a valid breath sample are, with one modification,
appropriate. The Court adopts the recommendation that the minimum breath volume requirement should be
lowered, for women over sixty years of age only, from 1.5 liters to 1.2 liters and concludes that this modification
does not violate equal protection rights. Regardless of minimum breath requirements, no test will be accepted by the
machine until the infrared measurement plateaus, which only occurs when a suspect is expelling deep lung air.
Further, while selectively lowering the breath volume requirement will create a different level at which women over
sixty may be charged with refusal, the record demonstrates that this group, and only this group, may not have the
physiological capability of providing a larger sample. In pending prosecutions, and in future prosecutions based on
tests conducted prior to the implementation of the Court’s directives, an Alcotest AIR with an insufficient volume
error message may not be used as evidence of refusal against women over the age of sixty, unless they also provided
another sample of at least 1.5 liters. (pp. 52-65)
3.
The Court declines to adopt the recommendation that a breath temperature sensor be added to the Alcotest,
concluding that this device is both unnecessary and impractical. The record includes scant evidence of a correlation
between breath temperature and increased breath alcohol concentration, and no evidence that the theoretical increase
in breath alcohol concentration would translate into an inaccurately elevated BAC. Further, any potential effect is
ameliorated by the 2100 to 1 blood/breath ratio and by use of truncated, rather than rounded, results, both of which
serve to underestimate results. Requiring the addition of a breath temperature sensor would also present an
unreasonable maintenance burden on New Jersey’s breath testing program. (pp. 65-71)
4.
A tolerance range of an absolute 0.01 percent (plus or minus 0.005 percent from the mean) BAC standard,
coupled with the use of a like percentage range of tolerance expressed as five percent plus or minus deviation from
the mean, is both scientifically appropriate and consistent with the intention of the Legislature in adopting per se
limits. The device must therefore be reprogrammed to comply with this standard. In pending prosecutions, and in
future prosecutions based on tests conducted prior to the implementation of the Court’s directives, in which the AIR
reports a BAC obtained using a doubled tolerance range, the reported breath samples must be reviewed to determine
whether the results meet this tolerance range. Any AIR that does not include two valid tests within tolerance under
this standard cannot be deemed to be sufficiently scientifically reliable to be admissible and shall not be admitted
into evidence as proof of a per se violation. (pp. 71-88)
5.
The Alcotest’s use of the fuel cell “drift” algorithm does not undermine its reliability. Scientific evidence
demonstrates that fuel cells begin to age as soon as they are put into service, and will eventually cause the Alcotest’s
electric chemical test to underestimate BAC. While there may be other means to compensate for this “drift,” those
means would not, in the end, be any more advantageous to defendants than the minor upward adjustment that the
algorithm effects. However, the Court adopts the Special Master’s recommendation that the devices be recalibrated
semi-annually instead of annually. A semi-annual calibration is consistent with the manufacturer’s
recommendations and provides a useful safeguard by affording a more regular opportunity to evaluate and replace
aging fuel cells. (pp. 89-95)
6.
The Court concludes that the Alcotest’s “weighted averaging” algorithm is an appropriate calculation that
results in a more accurate infrared measurement. It gives greater weight to the breath that, inevitably, includes the
deepest air drawn from the lungs. It therefore focuses the analysis on the portion of the breath sample that most
accurately represents the subject’s BAC. (pp. 95-96)
Page 3
3
7.
The buffer overflow error is a real error in the programming that may cause the Alcotest to report incorrect
results in situations involving a third breath sample, which is taken only when the measurements from the first two
tests are not in tolerance. The buffer overflow programming error, which must be corrected, affects only the final
BAC result reported on the AIR. Because the infrared and electric chemical measurements for all of the test
samples are accurately reported on the AIR, the correct BAC value can, and must, be computed from those
measurements by applying a corrective formula. In pending prosecutions, and in future prosecutions based on tests
conducted prior to the implementation of the Court’s directives, the State must review all AIRs that include three
tests, perform the calculations to identify the correct BAC in accordance with the corrective formula, and provide
that data to the court. The calculations must be made a part of the evidence in any prosecution to facilitate appellate
review. (pp. 96-102)
8.
The Court finds adequate support in the record that catastrophic error detection should be re-enabled in the
Alcotest. This detection will allow the machine to recognize catastrophic errors and respond by shutting down.
There is no basis for the Court to conclude that the lack of catastrophic error detection could result in an inaccurate
AIR in any pending prosecution. (pp. 102-103)
9.
The Court finds the overall programming style and design of the source code to be acceptable. The
exhaustive review undertaken in this case revealed few actual errors or issues within the source code. There being
no evidence in the record that any other asserted shortcomings are more than stylistic or theoretical challenges, the
Court declines to require any specific programming standards at this time. (pp. 104-105)
10.
In future revisions to the Alcotest software, the State must: have the Alcotest software locked so that only
the manufacturer can make revisions to the source code; have the software revised so that the Alcotest identifies and
prints the software version that it is utilizing on each AIR; and give detailed notice consistent with due process to the
public and the New Jersey State Bar Association of any future revisions. (pp. 105-107) more info at http://www.njlaws.com/statevchun.htm |
