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Dallas, TX  75248

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With a 91% success rate on cases announced for trial since 2002, our attorneys are prepared to fight hard in your name.

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Intoxilyzer 5000

If your breath test reading is over the legal limit, do not take for granted that you will be convicted of DUI.  You should understand that a breath test is by no means perfect evidence, and important defenses exist that can often lead to dropped or dismissed charges by prosecutors, or a judge or jury at trial.

An experienced DWI defense lawyer can use these defenses to the breath test to the advantage of your Dallas DWI case.

Dallas-Fort Worth DWI and the Intoxilyzer 5000

An arrest for DWI is a stressful process, and you may be led to think that you are already guilty if you blew over the legal limit during the breath test. However, this is simply not true. If you are facing a DUI in Dallas, Denton, Collin, Tarrant, Rockwall, Johnson, Wise, or Ellis Counties, contact the DWI legal defense team of Law Offices of Richard C. McConathy.

They will fight with you to protect your rights while exposing any weakness in the prosecution’s case involving breath test results or other DWI evidence. Your first consultation is free, so call (972) 233-5700 today to find out how Law Offices of Richard C. McConathy can help you resolve your DWI case in the Dallas area.


How the Intoxilyzer 5000 Works

The Intoxilyzer 5000 (I-5000) is a machine that uses infrared light absorption testing to detect the presence of alcohol.  A breath sample is first passed through the sample chamber; then, the machine sends several wavelengths of infrared light through the chamber in order to determine the quantity of light absorbed by the ethanol in the breath sample.

By knowing the beginning voltage of the signal and then measuring its voltage after the light has passed through, the operator uses the device to convert the analog signal produced into a digital reading.  The breath sample’s adequacy is based on minimum pressure, time and level slope. For this device, the process of breath alcohol measurement is largely hardware-driven.  The hardware uses analog comparators, resisters and other parts, which together create a current directed to the computer processor.

Though processed through computerized hardware, these results are not always 100% accurate. Additionally, during an arrest involving a breath test you still have rights and the officer still has procedures that he or she must follow. A qualified DWI defense attorney serving the metroplex can use the machine's inaccuracies and procedural errors to show cracks in the prosecution's case against you.


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Problems with the Intoxilyzer 5000 in Texas

New challenges have arisen in showing that the results of a particular machine are actually valid, because of problems with routine monthly and annual inspections.  Criminal defense attorneys fighting DFW DUI cases have proven on more than one occasion that these machines often fail routine monthly inspections, and yet are still used to collect evidence to present at court.

In many cases, agency inspectors falsify the reason given for a machine’s failing, claiming for instance that an "o-ring" failed or even unplugging the machine.  A glitch in the machine allows the inspector to unplug it, therefore "dumping" any record that has failed.  The only remaining evidence of such fraud is that an unexplained log-in has been recorded.

This is why a driver’s breath sample tests above the legal limit does not mean an automatic DUI conviction.  In fact, in the Dallas area, these DWU cases have a good chance of getting reduced to reckless driving or obstructing a highway, especially when attorneys can demonstrate any kind of procedural error with the Intoxilyzer 5000 sample.

Furthermore, there are certain individual factors that can cause concern with regards to breath test accuracy.  Factors like age, medical conditions causing abnormal lung function, acid reflux or GERD, dental work or dentures, or other physical abnormalities that might have occurred during the 20 minutes prior to the test could alter the results and make them inaccurate.

It is best to not take any tests regarding your blood alcohol content before or during your Dallas DWI arrest, but if you do submit to a test like the Intoxilyzer 5000, the skills and knowledge of an experienced Dallas DWI defense attorney could be the difference between a conviction and a more favorable outcome.


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Excluding Intoxilyzer 5000 Evidence in Dallas Courts

In many DWI cases in the Dallas area involving Intoxilyzer 5000 evidence, the goal of your experienced DWI defense lawyer is to exclude the breath test results.  This is usually done through making one or more specific pretrial motions. If the motion to exclude the evidence is granted by the judge or court, in trial the prosecutor cannot mention either the breath test or its results to the jury. DWI tests may be excluded from evidence presented at trial if:

  • The driver submits to the breath test before an arrest
  • Police violated the driver’s right to obtain an independent blood, breath or urine test
  • Police failed to substantially comply with rules or procedure regarding the Intoxilyzer 5000

Possible violations of the Intoxilyzer 5000 rules include:

  • Giving unauthorized individuals access to the breath testing device
  • Using tap water instead of distilled
  • Failing to allow the 20-minute observation period before breath testing
  • Failing to recognize the aforementioned medical conditions
  • Refusing to reveal to attorneys the machine’s code or other information regarding software or hardware flaws. 

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Law Offices of Richard C. McConathy | DWI Defense Lawyer Serving Dallas-Fort Worth

If you need to fight a DWI anywhere in Dallas-Fort Worth, including Richardson, Addison, Garland, Irving, Grapevine, Grand Prairie, Denton, Plano, Frisco, McKinney, Arlington, Mesquite, Carrolton, or Lewisville, contact the DWI lawyers of Law Offices of Richard C. McConathy.

They will fight to protect your rights and work to earn a favorable outcome in your DWI case. Call (972) 233-5700 today to schedule your free consultation.


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*Free consultation applies only for active criminal cases seeking to retain the office

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