Title: State v. Gregory A. Busch
Citation: N/A
Docket Number: 1996AP002822
State: Wisconsin
Issuer: Wisconsin Supreme Court
Date: April 30, 1998

SUPREME COURT OF WISCONSIN 
 
 
Case No.: 
96-2822 
 
 
Complete Title 
of Case: 
 
 
State of Wisconsin,  
 
Plaintiff-Respondent-Petitioner, 
 
v. 
Gregory A. Busch,  
 
Defendant-Appellant.  
 
ON REVIEW OF A DECISION OF THE COURT OF APPEALS 
Reported at: 
212 Wis. 2d 245, 569 N.W.2d 37 
 
 
 
(Ct. App. 1997-PUBLISHED) 
 
 
 
 
 
 
Opinion Filed: 
April 30, 1998 
Submitted on Briefs: 
 
Oral Argument: 
March 4, 1998 
 
 
Source of APPEAL 
 
COURT: 
Circuit 
 
COUNTY: 
Sheboygan 
 
JUDGE: 
L. Edward Stengel 
 
 
JUSTICES: 
 
Concurred: 
 
 
Dissented: 
 
 
Not Participating:  
 
 
ATTORNEYS: 
For the plaintiff-respondent-petitioner the cause 
was argued by Joseph DeCecco, assistant district attorney with 
whom on the briefs was Christopher W. Stock, deputy district 
attorney and James E. Doyle, attorney general. 
 
 
For the defendant-appellant there was a brief by 
Rebecca Lyman Persick, and Law Offices of Barry S. Cohen, S.C., 
Elkhart Lake and Christopher A. Mutschler, and Anderegg & 
Mutschler, LLP, Fond du Lac and oral argument by Dennis M. 
Melowski. 
 
 
 
1 
 
NOTICE 
This opinion is subject to further editing and 
modification.  The final version will appear in 
the bound volume of the official reports. 
 
 
No. 96-2822  
 
STATE OF WISCONSIN               :        
        
 
 
 
 
IN SUPREME COURT 
 
 
State of Wisconsin,  
 
          Plaintiff-Respondent-Petitioner, 
 
     v. 
 
Gregory A. Busch,  
 
          Defendant-Appellant.  
FILED 
 
APR 30, 1998 
 
Marilyn L. Graves 
Clerk of Supreme Court 
Madison, WI 
 
 
 
 
 
REVIEW of a decision of the Court of Appeals.  Reversed. 
¶1 
N. PATRICK CROOKS, J.  The State of Wisconsin 
("State") seeks review of a published decision of the court of 
appeals.1  The court of appeals reversed the circuit court's 
order denying Gregory A. Busch's ("Busch") motion to suppress 
evidence of the results of his breath alcohol test in which an 
Intoxilyzer 5000 Series 6600 machine was utilized to administer 
the test.  Busch argued that the Intoxilyzer Model 5000 Series 
6600 had not been evaluated by the Department of Transportation 
("DOT") prior to its use in the state in accord with Wis. Stat. 
§ 343.305(6)(b)(1993-94)2 and Wis. Admin. Code § TRANS 311.04 
                     
1 State v. Baldwin, 212 Wis. 2d 245, 569 N.W.2d 37 (Ct. App. 
1997).  At the court of appeals, the present case was 
consolidated with Baldwin.  This court granted Busch's petition 
for review, see State v. Busch, 212 Wis. 2d 687, 569 N.W.2d 589 
(1997), but denied Baldwin's petition for review, see State v. 
Baldwin, 212 Wis. 2d 688, 569 N.W.2d 590 (1997). 
2 All future references to the Wisconsin Statutes will be to 
the 1993-94 volumes. 
No.  96-2822 
 
2 
(January, 1993).3  Busch asserted that the Series 6600 is a 
modified version of the Intoxilyzer Model 5000 Series 6400, and 
although the Series 6400 had been appropriately evaluated and 
approved, the Series 6600 had not. 
¶2 
The circuit court for Sheboygan County, the Honorable 
L. Edward Stengel presiding, denied Busch's motion to suppress, 
finding that the changes made to the Series 6400 had not altered 
the analytical process of the machine.  Hence, the circuit court 
concluded that the Series 6600 had been "appropriately tested 
and [is] in compliance with both state statutes and the 
administrative code."  Accordingly, the breath alcohol test 
results were afforded a presumption of accuracy and admitted as 
evidence to establish Busch's breath alcohol concentration.  The 
circuit court subsequently convicted Busch of operating a motor 
vehicle with a prohibited alcohol concentration contrary to Wis. 
Stat. § 346.63(1)(b), and Busch appealed. 
  
¶3 
The court of appeals reversed the judgment of the 
circuit court.  The court of appeals determined that the 
numerous changes to the Series 6400 did not result in a similar 
hybrid-type Series 6600; rather, a new quantitative breath 
testing instrument had been created.  Before test results from 
the Series 6600 could be afforded a presumption of accuracy, the 
court of appeals determined it must be tested, evaluated, and 
approved in accord with Wis. Admin. Code § TRANS 311.04.  The 
                     
3 All future references to the Wisconsin Administrative Code 
will be to the January, 1993 version. 
No.  96-2822 
 
3 
court of appeals remanded the case to the circuit court to allow 
the State to present evidence that the breath alcohol test 
results obtained by use of the Intoxilyzer Model 5000 Series 
6600 were accurate and reliable.   
¶4 
We conclude that under Wis. Admin. Code § TRANS 
311.04(1), the chief of the chemical test section of the DOT is 
charged with approving all instruments used for the quantitative 
analysis of alcohol in the breath.  We also conclude that under 
§ TRANS 311.04(2) the chief of the chemical test section must 
evaluate all models of breath testing instruments, but is given 
the authority to determine the procedures for the evaluation of 
such instruments.  In the present case, the circuit court 
received detailed testimony from the DOT that the Series 6600 
had not been separately evaluated prior to approval because the 
modifications did not alter the analytical functioning of the 
Series 6600, and that the Series 6400 had been previously 
evaluated.  Based upon this testimony, we conclude that the 
circuit court did not erroneously exercise its discretion in 
finding that 
the 
Series 
6400 and 
the Series 
6600 
were 
essentially the "same machine" due to their identical analytical 
processing.  We further conclude that the DOT's interpretation 
that the method of testing of the Series 6600 had been 
previously evaluated and approved is consistent with Wis. Stat. 
§ 343.305(6)(b) 
and 
§ TRANS 
311.04, 
the 
latter 
of 
which 
authorizes the chief of the chemical test section to determine 
the procedures for evaluation.  Accordingly, Busch's breath 
alcohol test results obtained by utilization of the Intoxilyzer 
No.  96-2822 
 
4 
Model 5000 Series 6600 are afforded a presumption of accuracy 
and reliability, since a machine identical in analytical 
functioning has already been tested, evaluated, and approved for 
use in this state. 
A. 
¶5 
The facts are undisputed.  On June 2, 1996, Busch was 
driving his motor vehicle and was stopped by a Trooper of the 
Wisconsin State Patrol.  The stop resulted in Busch being cited 
with one count of operating a motor vehicle while under the 
influence of an intoxicant (first offense) contrary to Wis. 
Stat. § 346.63(1)(a) and one count of operation a motor vehicle 
with a prohibited alcohol concentration (first offense) contrary 
to Wis. Stat. § 346.63(1)(b).  Busch was transported to the 
Sheboygan Falls Police Department, where he agreed to submit to 
a chemical test of his breath.  The chemical test was conducted 
using the Intoxilyzer Model 5000 Series 6600, and the test 
results indicated that Busch's alcohol concentration was above 
the legally prohibited alcohol concentration set forth under 
Wis. Stat. § 340.01(46m). 
¶6 
On August 14, 1996, Busch filed a motion to suppress 
the chemical test results.  He asserted that in accord with Wis. 
Stat. § 343.305(6)(b), the DOT had promulgated Wis. Admin. Code 
§ TRANS 311.04 to outline procedures for the evaluation and 
approval of breath alcohol test instruments, and that such 
evaluation and approval must occur prior to use of a breath 
testing instrument.  Busch specifically referenced § TRANS 
No.  96-2822 
 
5 
311.04(2)(a) which states that "[a]ll models of breath testing 
instruments and ancillary equipment used shall be evaluated by 
the chief of the chemical test section."  He argued that the 
Intoxilyzer Model 5000 Series 6600 had not been evaluated for 
use by the chief of the chemical test section.  The Series 6600 
was a modified version of the Intoxilyzer Model 5000 Series 
6400.  Busch asserted that although the Series 6400 had 
previously been evaluated and approved, the Series 6600 had not. 
¶7  A motion hearing and court trial was held on August 28, 
1996.  At the hearing, the parties acknowledged that the 
substance of the motion to suppress had previously been heard 
and ruled upon by the circuit court in a factually similar case. 
 See State v. Baldwin, No. 96-1013-CR (1997).  The parties in 
the present case stipulated to the adoption of the testimony and 
arguments that the parties presented to the circuit court in 
Baldwin.4   
¶8 
At the hearing on the motion to suppress in Baldwin, 
defense counsel called George Menart to testify.  At the time, 
Menart had worked for approximately 13 years as a senior 
electronics technician for the Division of State Patrol, 
Chemical Testing, which is a part of the DOT.  Menart testified 
that the State Patrol and the DOT set the standards for the 
breath testing program in Wisconsin, set forth the provisions in 
                     
4 The presiding circuit court judge in this case, Judge L. 
Edward Stengel, also presided in the Baldwin case, and defense 
counsel at the circuit court in this case was also defense 
counsel at the circuit court for Randall Baldwin.   
No.  96-2822 
 
6 
the administrative code that guide the program, set the 
standards for the testing of the breath test instruments and the 
training of persons operating the test instruments, provide all 
equipment for testing, and also provide the service and 
calibration of the testing instrumentation.  Menart stated that 
he 
had 
military 
and 
technical 
electronics 
training, 
was 
affiliated 
with the International 
Association 
of Chemical 
Testing, and held a professional certification with the DOT.  
Menart also testified that he had received extensive training on 
the theory, repair, and calibration of breath testing equipment 
from the manufacturer of the Intoxilyzer Model 5000.  Finally, 
Menart 
testified 
that 
he 
had 
tested 
and 
evaluated 
the 
Intoxilyzer Model 5000 Series 6400 as part of the original 
approval procedures in 1983 or 1984. 
¶9 
Menart testified that there were seven modifications 
made to the Series 6400, resulting in the Series 6600.  First,  
additional circuitry was added to the processor board to set up 
an internal calibration system in the device.  Menart stated 
that that this system is not used in Wisconsin.  Second, the 
device used to heat the breath sample chamber was moved from an 
external mount underneath the sample chamber onto the mother 
board,5 because the external mount had become obsolete.  Third, 
the power supply had been replaced by a newer model because the 
                     
5 Menart defined the mother board as the system to which all 
the electronics are plugged in.  "Essentially what it is is a 
means of getting data transferred back and forth between the 
different systems." 
No.  96-2822 
 
7 
model previously used had become obsolete.  The power supply 
voltage 
remained 
identical. 
 
Fourth, 
diodes, 
capacitors, 
resistors, transistors, and chips on the mother board were 
obtained from a different manufacturer; however, all met the 
specifications required by the DOT.  Fifth, the memory was 
upgraded from 16 kilobytes to 32 kilobytes.  Sixth, a phone 
activated timer was added so that the State Patrol could 
download the information from individual machines state-wide to 
the main DOT files on a weekly basis.  Seventh, a 10,000 ohm 
resistor was added to bleed the capacitor. 
¶10 Menart stated that the numerous changes in the Series 
6600 
did 
not 
affect 
the 
analytical 
functioning 
of 
the 
instrument, and that the method of analysis in the Series 6600 
was identical to the method of analysis in the Series 6400.  
Menart acknowledged that the Series 6600 had never been 
separately tested and evaluated.  However, it was the position 
of the DOT that the Series 6600 was essentially the same machine 
as the Series 6400.   
 
When we looked at equipment differences, especially 
from the perspective of how an instrument operates and 
how it does it's [sic] evaluation, what we look at is 
the optical bench, which entails the sample chamber, 
the lenses, the infrared source, the detector and, 
also, how that signals or multiple signals are then 
processed and in the case of the sixty-four and the 
6600 series, the optical bench is identical.  They're 
interchangeable.  They haven't changed a bit.  The 
specifications are the same; the processor board is 
the same; the way the analysis or the 3 wavelengths 
are 
done; 
the 
way 
the 
comparisons 
are 
done, 
ultimately, to create one signal, which is converted 
from analogue to digital.   
No.  96-2822 
 
8 
 
 . . .  
 
The integrated circuits are identical to what they 
were 10, 12 years ago.  The capacitor values, the 
resistor values are, essentially, all the same.  The 
manufacturers may have changed, but the components 
themselves are identical. 
¶11 In ruling on the motion to suppress in Baldwin, the 
circuit court found that based upon the testimony of Menart, the 
two machinesSeries 6400 and Series 6600were identical with 
respect to the analytical process.  The circuit court concluded 
that it was satisfied that the DOT had determined that no 
additional testing of the Series 6600 was necessary and, 
therefore, the DOT had met its responsibility under the 
administrative code.  Accordingly, the circuit court accepted 
the Series 6600 as being appropriately tested and in full 
compliance with Wis. Stat. § 343.305(6)(b) and Wis. Admin. Code 
§ TRANS 311.04. 
¶12 Based upon the testimony presented in Baldwin, as 
incorporated by the parties in the present case, the circuit 
court denied Busch's motion to suppress the breath alcohol test 
results.  Busch stipulated that there was probable cause for his 
arrest, and that he failed the field sobriety tests administered 
by the State Trooper on the date that he received the citations 
at issue.  The circuit court found Busch guilty of both counts. 
  
¶13 On September 13, 1996, the circuit court entered an 
Order of Judgment convicting Busch of operating a motor vehicle 
with a prohibited alcohol concentration contrary to Wis. Stat. 
No.  96-2822 
 
9 
§ 346.63(1)(b).  The circuit court dismissed the count of 
operating a motor vehicle while under the influence of an 
intoxicant 
contrary 
to 
§ 346.63(1)(a) 
in 
accordance 
with 
§ 346.63(1)(c).6  Busch appealed. 
¶14 The court of appeals reversed the judgment of the 
circuit court, concluding that the DOT had failed to comply with 
 Wis. Admin. Code § TRANS 311.04.  The court of appeals 
determined that pursuant to Wis. Stat. § 343.305(6)(b) and Wis. 
Admin. Code § TRANS 311.04, the DOT is required to test and 
certify breath test equipment prior to any use of the equipment 
in the state of Wisconsin.  Absent testing and evaluation of a 
particular machine, the court of appeals reasoned, there is no 
certification that the instrument and its analysis are accurate 
and reliable.  The court of appeals recognized that an 
administrative agency's interpretation and application of its 
own rules are afforded great weight.  However, the court of 
appeals determined that the DOT's conclusion that the Series 
6600 and the Series 6400 are the same machine did not meet the 
requirements of evaluation and approval under § TRANS 311.04.  
The court of appeals concluded that failure of the DOT to 
                     
6 Wisconsin Stat. § 346.63(1)(c) states in relevant part: 
A person may be charged with and a prosecutor may 
proceed upon a complaint based upon a violation of 
par. (a) or (b) or both for acts arising out of the 
same incident or occurrence.   . . .   If the person 
is found guilty of both pars. (a) and (b), for acts 
arising out of the same incident or occurrence, there 
shall 
be 
a 
single 
conviction 
for 
purposes 
of 
sentencing 
and 
for 
purposes 
of 
counting 
convictions . . . .  
No.  96-2822 
 
10
evaluate and approve the Series 6600, which contained seven 
major modifications from the previously tested Series 6400, 
stripped the machine of any presumption of accuracy.  The court 
of appeals remanded the case to the circuit court to allow the 
State to present evidence that the Series 6600 breath alcohol 
test results of Busch's breath are accurate and reliable. 
B. 
¶15 Busch's claim presents an issue of the interpretation 
and application of an administrative regulation, namely, Wis. 
Admin. Code § TRANS 311.04.  Administrative rules promulgated 
pursuant to a power delegated by the legislature "should be 
construed together with the statute to make, if possible, an 
effectual piece of legislation in harmony with common sense and 
sound reason."  Law Enforcement Standards Bd. v. Village of 
Lyndon Station, 101 Wis. 2d 472, 489, 305 N.W.2d 89 (1981).  
When interpreting an administrative regulation, we generally use 
the same rules of construction and interpretation as applicable 
to statutes.  See id.   
¶16 An issue of statutory interpretation is one which we 
review de novo, benefiting from the analyses of the circuit 
court and the court of appeals.  See Carlson & Erickson Builders 
v. Lampert Yards, 190 Wis. 2d 650, 658, 529 N.W.2d 905 (1995).  
However, "[a]n administrative construction of the agency's own 
regulations is controlling in determining their meaning unless 
plainly erroneous or inconsistent with the regulations."  Lyndon 
Station, 101 Wis. 2d at 490.  See also State ex rel. Durando v. 
No.  96-2822 
 
11
State Athletic Comm'n, 272 Wis. 191, 195, 75 N.W.2d 451 (1956) 
("[A]n administrative [agency's] interpretation of its own 
rules . . . should be accorded great weight by the courts 
'unless it is plainly erroneous or inconsistent' with the 
regulations."  (quoting Bowles v. Seminole Rock & Sand Co., 325 
U.S. 410, 414 (1945)).  In addition, we will not reverse any 
findings of fact made by the circuit court unless they are 
clearly erroneous.  See State v. Smith, 207 Wis. 2d 258, 266, 
558 N.W.2d 379 (1997). 
¶17 The Wisconsin Legislature has delegated to the DOT the 
authority and responsibility of evaluating and approving the 
instrumentation used to administer chemical breath alcohol 
tests.  Wisconsin Stat. § 343.305(6)(b) states in relevant part: 
 
The 
department 
of 
transportation 
shall 
approve 
techniques or methods of performing chemical analysis 
of the breath and shall: 
 
 
 . . .  
 
3.  Have trained technicians, approved by the 
secretary, test and certify the accuracy of the 
equipment to be used by law enforcement officers for 
chemical analysis of a person's breath . . . before 
regular 
use 
of 
the 
equipment 
and 
periodically 
thereafter at intervals of not more than 120 days; 
¶18 In accordance with Wis. Stat. § 343.305(6)(b), the DOT 
promulgated guidelines in the administrative code for the 
administration of the breath alcohol testing program.  Wisconsin 
Admin. Code § TRANS 311 states in relevant part: 
 
Trans 311.01 Purpose.  The purpose of this chapter is 
to aid the department of transportation in the 
administration of the breath alcohol testing, approval 
No.  96-2822 
 
12
and permit program as directed and authorized by s. 
343.305(6)(b), Stats. 
 . . .  
 
Trans 
311.04 
Approval 
of 
breath 
alcohol 
test 
instruments.  (1) Only instruments and ancillary 
equipment approved by the chief of the chemical test 
section 
may 
be 
used 
for 
the 
qualitative 
or 
quantitative analysis of alcohol in the breath; 
 
(2)(a) All models of breath testing instruments and 
ancillary equipment used shall be evaluated by the 
chief of the chemical test section. 
 
(b) The procedures for evaluation shall be determined 
by the chief of the chemical test section. 
 
(3) Each type or category of instrument shall be 
approved by the chief of the chemical test section 
prior to use in this state. 
 
Note:  The following quantitative breath alcohol test 
instruments are approved for use in Wisconsin: 
 
Intoxilyzer Model 5000 
Intoxilyzer Model 1400 
Intoxilyzer 5000 Model 000568 
¶19 In 
In 
re 
Suspension 
of 
Operating 
Privilege 
of  
Bardwell, 83 Wis. 2d 891, 900, 266 N.W.2d 618 (1978), this court 
held that "[a] chemical test specified by a statute may not be 
deemed unreliable as a matter of law."  Thus, a "recognized 
method[] of testing authorized by statute [is] entitled to a 
prima facie presumption of accuracy."  State v. Disch, 119 
Wis. 2d 461, 475, 351 N.W.2d 492 (1984).  Accordingly, if a 
breath alcohol instrument's "method[] of testing" has been 
recognized as accurate and complies with the specifications of 
Wis. Stat. § 343.305(6)(b) and Wis. Admin. Code § TRANS 311.04, 
No.  96-2822 
 
13
it is afforded a presumption that its test results are accurate 
and reliable.  See id.  
¶20  Wisconsin Admin. Code § TRANS 311.04(1) states that 
the chief of the chemical test section of the DOT must approve 
any equipment used in administering a quantitative breath 
alcohol test.  Section TRANS 311.04(2)(a) further states that, 
as part of the DOT's approval of the breath testing equipment, 
all models of equipment must be evaluated.7  However, § TRANS 
311.04(2)(b) 
expressly 
states 
that 
the 
"procedures 
for 
evaluat[ing]" a given breath alcohol test instrument "shall be 
determined by the chief of the chemical test section" of the 
DOT.   
¶21 Notwithstanding the DOT's authority, we recognize that 
"[a] scientific or medical method not recognized as acceptable 
in the scientific or medical discipline as accurate does not 
enjoy the presumption of accuracy."  State v. Trailer Serv., 
Inc., 61 Wis. 2d 400, 408, 212 N.W.2d 683 (1973).  However, 
where the method of testing has been recognized as accurate and 
reliable, the particular test instrument "need not be proved for 
reliability in every case."  Id.   
                     
7 Busch argues that the language of Wis. Admin. Code § TRANS 
311.04 is mandatory.  We accept this argument and decline to 
engage in a lengthy discussion regarding whether the language is 
mandatory or directory.  The State does not dispute that the DOT 
"shall" evaluate and approve breath alcohol testing instruments; 
rather, the State asserts that the Intoxilyzer Model 5000 Series 
6600 was evaluated and approved consistent with § TRANS 311.04 
and Wis. Stat. § 343.305(6)(b). 
No.  96-2822 
 
14
¶22 In the present case, the DOT's determination that the 
Series 6600 method of breath alcohol testing did not require 
further evaluation prior to approval was not "plainly erroneous 
or inconsistent with the regulations," either in its language or 
its purpose.  See Lyndon Station, 101 Wis. 2d at 490.  In 
addition, the DOT's interpretation and application of Wis. 
Admin. Code § TRANS 311.04 are consistent with this court's 
decisions which state that a scientific method of testing may be 
afforded a presumption of accuracy if it has been recognized as 
an acceptable method of testing.  See, e.g., Trailer, 61 Wis. 2d 
at 407-08. 
¶23 As indicated, Wis. Admin. Code § TRANS 311.04 states 
that the DOT is required to evaluate all breath test instrument 
models; however, the method of evaluation is left to the 
determination of the DOT.   Section TRANS 311.04(1) states that 
the purpose of the regulation is, in part, to aid the DOT in 
approving the breath alcohol testing program in Wisconsin 
consistent with Wis. Stat. § 343.305.   The purpose of the 
implied consent law set forth in § 343.3058 is to keep the 
highways safe for the public, which includes  "obtain[ing] the 
blood alcohol content in order to obtain evidence to prosecute 
drunk drivers."  State v. Nordness, 128 Wis. 2d 15, 33, 381 
                     
8 Wisconsin Stat. § 343.305 is known as the implied consent 
law because it "states that any person who drives or operates a 
motor vehicle upon the public highways of this state is deemed 
to have given his consent for chemical testing when requested to 
do so by a law enforcement officer."  State v. Nordness, 128 
Wis. 2d 15, 24-25, 381 N.W.2d 300 (1986). 
No.  96-2822 
 
15
N.W.2d 300 (1986).  Although not expressly stated in § 343.305, 
it is reasonable to infer that the Wisconsin Legislature 
intended any breath alcohol testing equipment to be accurate and 
reliable, and the DOT's regulations expressly state that any 
instrumentation must be evaluated and approved.   
¶24 In the present case, Menart testified on behalf of the 
DOT that the analytical process, that is, the method of breath 
testing, of the Series 6600 had been approved because a machine 
identical in analytical functioning had been tested, evaluated, 
and approved as to accuracy and reliability for use in the 
state. 
 
The 
DOT's 
determination 
of 
the 
"procedure 
for 
evaluation" of the Series 6600 in accord with Wis. Admin. Code 
§ TRANS 311.04(2) was to consider the modifications made, to 
consider whether the method of analysis had been altered or 
affected, and to ultimately conclude that the particular method 
of analysis utilized by the Series 6600 had already been 
evaluated and approved in the Series 6400.   
¶25 In reviewing the DOT's interpretation of Wis. Admin. 
Code § TRANS 311.04, the circuit court did not erroneously 
exercise its discretion in concluding that the Series 6400 and 
the Series 6600 were analytically the "same machine."  The 
circuit court heard testimony from Menart as a trained, 
experienced representative of the DOT who participated in 
evaluating, approving, and servicing instruments used for breath 
alcohol testing in the state of Wisconsin.  Menart testified to 
several modifications made to the Series 6400 which resulted in 
the Series 6600.  Menart addressed each of these changes, 
No.  96-2822 
 
16
stating that none had any effect on the analytical processing or 
the method of breath testing of the machine.  He testified that 
the DOT carefully evaluated the Series 6600 machine and 
determined that repetitive testing of an analytical process 
identical to the Series 6400 was not necessary.  Thus, the 
finding by the circuit 
court that 
the Series 
6600 was 
essentially the same machine as the Series 6400 was not an 
erroneous exercise of the circuit court's discretion. 
¶26 The DOT's interpretation and application of its own  
regulation are consistent with Wis. Admin. Code § TRANS 311.04 
and Wis. Stat. § 343.305(6)(b).  It is also consistent with this 
court's decisions stating that a "recognized method of testing 
authorized by statute" is afforded a prima facie presumption of 
accuracy.  Disch, 119 Wis. 2d at 475.  Thus, the DOT's 
interpretation of § TRANS 311.04 is not "plainly erroneous or 
inconsistent with the regulations."  Lyndon Station, 101 Wis. 2d 
at 490.  Accordingly, the DOT's construction of its own 
regulation is controlling.  See id.9 
¶27 The failure of the DOT to add the "Intoxilyzer Model 
5000 Series 6600" to the note following Wis. Admin. Code § TRANS 
311.04, which sets forth the instruments that are approved for 
                     
9 Our holding is in no way premised upon the distinction 
that the manufacturer of the 6600 machine designated it as a 
"series" and Wis. Admin. Code § TRANS 311.04 requires that the 
chief of the chemical test section of the DOT need only approve 
equipment "models."  Such a distinction would place too great 
authority in the hands of the various equipment manufacturers in 
designating a particular machine as a "series" or a "model." 
No.  96-2822 
 
17
use, does not alter our analysis.  First, the note states that 
the Intoxilyzer Model 5000 is approved for use in the state 
without designating any series number, including the Series 6400 
which has been evaluated and approved by the DOT.  Since it is 
the position of the DOT that the Series 6400 and the Series 6600 
are the "same machine," it is understandable why the DOT did not 
amend the note to specifically designate that the Series 6400 
and the Series 6600 were separately evaluated and approved for 
use.  We recognize that the Intoxilyzer 5000 Model 000568 was 
specifically added to the note list; however, Menart testified 
before the circuit court that the Model 000568 and the Series 
6400 are as "different as night and day."   
¶28 Second, although the note is helpful in interpreting 
and applying Wis. Admin. Code § TRANS 311.04, it is only one 
factor for us to consider in our analysis.  In this case, we 
also 
have 
the 
benefit 
of 
the 
administrative 
agency's 
interpretation of § TRANS 311.04, which is consistent with the 
regulation and the enabling statute, Wis. Stat. § 343.305(6)(b). 
 Examining the content of the note in conjunction with the DOT's 
interpretation of the regulation, we are convinced that the 
DOT's construction of § TRANS 311.04 is controlling. 
C. 
¶29 In sum, we conclude that under Wis. Admin. Code 
§ TRANS 311.04, the chief of the chemical test section of the 
DOT is charged with evaluating and approving all instruments 
used for the quantitative analysis of alcohol in the breath.  We 
No.  96-2822 
 
18
also conclude that the chief of the chemical test section is 
given the authority to determine the procedures for the 
evaluation of such instruments.  Based upon the detailed 
testimony presented by the DOT to the circuit court, we conclude 
that the circuit court did not erroneously exercise its 
discretion in finding that the Series 6400 and the Series 6600 
were essentially the "same machine" due to their identical 
analytical processing.  We further conclude that the DOT's 
interpretation that the method of testing of the Series 6600 had 
been previously evaluated and approved is consistent with Wis. 
Stat. § 343.305(6)(b) and § TRANS 311.04.  Accordingly, Busch's 
breath alcohol test results obtained by utilization of the 
Intoxilyzer Model 5000 Series 6600 are afforded a presumption of 
accuracy and reliability. 
By the Court.—The decision of the court of appeals is 
reversed.