1005 N. Marion St.
Tampa, FL 33602
813.250.0500

Attorney for the DUI Breath Test

Never assume that a breath test reading over the legal limit means that you will be convicted of driving under the influence of alcoholic beverages (DUI). Even if your reading is well over the legal limit, important defenses exist that might lead to charges being dismissed by the trial court or dropped by the prosecutor. In many of these cases, your attorney will fight to get the breath test results suppressed or excluded at trial.

Click here to read more about our Recent Case Results in DUI Cases.

The goal in many cases is getting the DUI reduced to a less serious charge such as "reckless driving." If you were arrested for DUI and blew over the legal limit of .08 then contact an experienced criminal defense attorney at the Sammis Law Firm.

The attorneys at the Sammis Law Firm focus on DUI defense and breath test DUI cases in Tampa and Hillsborough County, FL. Call 813-250-0500 to discuss your case today.


Pre-trial Motions to Exclude the Intoxilyzer BAC Reading

In many of these cases our goal is to have the breath test reading completely excluded so that if the case goes to trial the prosecutor is not able to tell the jury that the client took the breath test or blew over the legal limit. Issues regarding the breath test instrument can include:

  • The individual submits to the breath test before an arrest which is not allowed under Florida law;
  • The right to obtain an independent blood, breath or urine test was violated;
  • The breath test operator failed to comply with rules regarding the Intoxilyzer, including:
    • the breath test operator was not properly permitted to administer the test;
    • the agency inspector was not properly permitted to maintain the breath test machine;
    • some unauthorized person had assess to the breath test instrument;
    • the officer failed to comply with the 20-minute observation period before breath testing;
    • the driver's medical condition such as Gerd, acid reflux, or dentures lead to an inaccurately high reading because of irregularities in the way the breath test operator administered the test;
  • Filing motion to obtain the source code or other information about flaws in the instrument that impact the accuracy or reliability of the breath testing;
  • Showing the agency inspectors failure to follow certain procedures related to the menu options, calibration procedures, or set up procedures; or
  • Filing motions to inspect the breath test instrument and testing environment.

Many problems can potentially affect a subject's breath test on Florida's Intoxilyzer 8000 including:

  • partition ratios;
  • body temperature;
  • alcohol pharmacokinetics and pharmacodynamics;
  • error ratios;
  • mouth alcohol detection;
  • breath volume issues;
  • out-of-tolerance results;
  • gastrointestinal reflux disorder;
  • radio frequency interference (RFI);
  • the absorption and elimination of alcohol from the body, and
  • potential maintenance tests that could have been performed or the regularity of performance of other possible maintenance tests,
  • Widmark's formula and calculation.

Trial Issues to Contest the Breath Test Reading and Intoxilyzer Results

Just because the driver blew over the legal limit does not mean that a DUI conviction cannot be avoided. In fact, in Hillsborough County, these DUI cases are often reduced to reckless driving, especially when any kind of mistake with the testing procedure can be shown.

Additionally, individual factors affecting the driver can cause concern with the admissibility of the breath test including:

  1. The driver's age or other factors impacting normal lung function;
  2. Conditions that could cause "mouth alcohol" including dental work or dentures;
  3. Medical conditions such as acid reflux or GERD;
  4. Anything abnormal that occurred during the 20 minute observation period before the test occurred;

Definitions in DUI Breath Test Cases

Florida law defines certain terms in breath test cases including:

  • Breath Alcohol Level - the term "breath alcohol level" (BAL) or "breath alcohol centration" (BAC) is defined as the ratio or alcohol by weight in a person's breath based upon grams of alcohol per 201 liters of breath (g/201L).
  • Breath Test Operator - the term "breath test operator" is defined as a person who has been issued a Breath Test Operator permit by the Florida Department of Law Enforcement.
  • Evidentiary Breath Test Instrument - a breath test instrument approved by the Florida Department of Law Enforcement under Rule 11D-8.003 F.A.C. and used primarily to conduct alcohol breath tests.

The Intoxilyzer 5000 versus the Intoxilyzer 8000

Both the Intoxilyzer 5000 (I-5000) and the Intoxilyzer 8000 (I-8000) are devices that determine the presence of alcohol through infrared light absorption testing. The machines require that a breath sample is passed through the sample chamber. The machine then sends infrared light of several wavelengths through the chamber seeking to determine how much light has been absorbed by the ethanol in the breath sample.

The theory behind the machine is that by knowing the beginning voltage of the signal and measuring the voltage of the signal after the light has passed through, the device then converts the analog signal produced into a digital reading.

The Intoxilyzer requires a sufficient breath sample in order to obtain a proper sample for analysis. For the I5000, the adequacy of a sample was based upon minimum pressure, time and level slope. For the I8000, the adequacy of the sample is based upon minimum volume, time, and slope.

Pressure refers to a minimum amount of force necessary to trip the pressure switch. In the Intoxilyzer 8000, pressure refers to a minimum amount of force required to trip the pressure transducer. Slope refers to the instrument measuring small differences during the blow to help in determining whether mouth alcohol is present in the sample.

In theory, the I8000 is suppose to distinguish between mouth alcohol and the deeper lung air that provides the ideal sample. The I8000 uses pressure (which is measured by the flow of breath) and time of blow to determine if sufficient volume has been introduced into the device.

An important difference between the Intoxilyzer 5000 and the Intoxilyzer 80000 is the amount of calculations done in the software of the machine as opposed to the hardware of the machine. For the I5000, the process of measuring breath alcohol was largely hardware driven, The hardware used analog comparators, resisters and other parts providing a current to the computer processor.

On the other hand, in the I8000, the vast majority of the calculations are assigned to computer components. For instance, in the I5000, the machine required a minimum of a 6 (six) second blow in order to make sure a sufficient volume allowed for the slope detector to work properly.

The Intoxilyzer 8000 assigns this determination of determining a sufficient sample to a computer that makes a determination of time and flow. Then that determination is compared to other readings obtained throughout the blow. The computer within the machine must also detect interferent substances. As you can see, the Intoxilyzer 8000 assigns a much larger number of functions to the computer embedded in the device.


Arguments that the Machine is Not "Approved" Under Florida Law

Previous challenges have been litigated over the fact that the Intoxilyzer 8000 is not an "approved" machine under Florida Law. Florida law requires that the alcohol testing program of the Florida Department of Law Enforcement Enforcement (FDLE) must evaluate only those machines that are listed on the Conforming Products List (CPL) of the U.S. Department of Transportation.

The CPL names the Intoxilyzer 8000 manufactured by CMI specifically, but further provides that the machine "...analyzes breath samples using the 3.4- and 9-micron bandwidth." The problem is that the Intoxilyzer 8000 used in Florida does not use the 9 micron or 3.4 micron bandwidth. Since the Intoxilyzer 8000 used in Florida is not the same machine as what is listed on the CPL then it should not be considered an "approved" machine under the Florida statutes.


The Intoxilyzer 8000 Only Uses Two Filters

Although CMI refused to disclose the specifications for years, in the summer of 2009, CMI disclosed that in the Infrared Filter specifications the center wavelength of the Infrared filters is determined to the three decimal place accuracy. The Intoxilyzer 8000 uses two narrowband Infrared filters with a center wavelengths at 3.476 microns and 9.376 microns.

One of the biggest programs with this machine is that it only uses two filters. The Intoxilyzer 5000 used 3 filters, the Intoxilyzer 5000 EN used 5 filters, and the Intoxilyzer 9000 has 4 filters. By using only two filters the chances that the machine might interpret an interferent as alcohol is greatly increased. 

The result is reported solely based on the 9.376 micron bandwidth, and the 3.467 bandwidth is used only to attempt to detect an interferent. The software is allegedly programs to report the error - "interferent detected" - if the readings from each bandwidth have a 10% disparety.


"Pulling the Plug" on the Intoxilyzer 8000

New challenges have been brought not based on the bandwidth issue, but in order to show that a particular machine is not approved because of problems with the routine monthly and annual inspections.

Criminal defense attorneys have shown that these machines often fail the routine monthly inspections. In many cases, the agency inspectors falsify the reason that the machine failed (for instance they claim that an "o-ring" failed). In some cases, the departmental inspectors are caught unplugging the instruments or otherwise causing a power outage.

The Florida software was configured so that the agency or departmental inspector can "dump" any record that the machine failed an inspection by unplugging the instrument or otherwise causing a power outage.. The only evidence left behind is the fact that a log in occurred that cannot be explained.

The most recent occurrence of this type of questionable power outage occurred during a routine inspection on 80-001731 on 5/06/13 when Agency Inspector Roger Skipper reported that a surge protector fell out of the wall and turned the machine off during an inspection. All data was lost and Roger Skipper did not fill out a Form 40 to properly document the non-compliance. Instead, the facts were hidden in an interoffice memo which did not comply with 11D-8 rules.


Hiding the "Source Code" to this Mysterious Machine

The results of the breath test machine should not be admissible because the State of Florida and the manufacturers of the machine are hiding the "source code" of the machine, and without the "source code" there is no way to determine if the machine really works.

Previous rulings throughout the State have held that the DUI defense attorney is not entitled to see the source code of the breath machine or to have an expert witness look at the source code of the breath test machine.

Those cases, however, hinged on the fact that the DUI attorney did not make a specific showing at the hearing that the source code was relevant or that any flaw existed with the Intoxilyzer 8000 that would make examination of the source code necessary.


Problems with the Intoxilyzer 8000 When Used in a Mobile Unit

In many cases, the arresting officer will ask the person arrested for DUI to submit to a breath test on an Intoxilyzer 8000 that is located in a mobile unit which is often the officer's vehicle or another officer's vehicle. These roadside breath tests occur at the scene before the subject is transported to the jail.

Additional problems can occur when the breath test on the Intoxilyzer occurs at the roadside. It is well-documented that the subject tests on these machines have a higher number of Radio Frequency Interferance (RFI) error / exception messsage.

The rules for breath testing require the breath test operator to clear the room when RFI is detected during the subject's test by removing all electrical equipment nearby. This is impossible at the roadside because the BTO has no idea what is causing the interference by radio frequence. The problem could be caused by a cell phone or other electrical equipment in a parked vehicle nearby, a cell phone tower, a WiFi router, or even nearby powerlines. 

When RFI is detected but the source of the radio frequence is not correctly determine, the next reading is completely unreliable because radio frequency could be affecting the machine in ways that do not trigger the RFI error / exception message.

Another problem with the Intoxilyzer 8000 breath test machines in the back of police cars is that they are not always connected to a reliable power source. Any power surge can impact the accuracy and reliablity of the reading.

Also, containimates in the environment can cause problems for the Intoxilyzer 8000 which are more serious at the roadside when compared to a controlled environment in a testing facility located in a secure building. For example, many DUI enforcement officers in Tampa and throughout Hillsborough County use a higher ethanol blend of fuel for the vehicle. In some cases those chemicals can infer with the reading and cause much higher reading especially when the vehicle was running or the machine was located near the exhaust system.


Fighting to the DUI Breath Test Case in Tampa, Hillsborough County, FL

At the Sammis Law Firm we have filed similar motions to contest these issues in Hillsborough County, FL. As the judges become more familiar with the problems with Florida's Intoxilyzer 8000, it becomes increasingly likely that the judges exclude the breath test results when a serious problem is found.

If you are accused of DUI in Tampa or Hillsborough County, FL, after submitting to a breath test and blowing over the legal limit then call us to discuss your case.


This article was last updated by Leslie M. Sammis on Friday, April 21, 2017.