Should I take the breath test or blood test?


I never urge anyone to take the breath test because it has serious problems accurately determining the quantity of ethyl alcohol present in a breath sample.  The machine is useful in determining whether any alcohol is present, but deficiencies in the machine make test results unreliable.  Risking one's freedom, marriage, job, driver's license, auto insurance rate, and loads of money on a breath test which is inherently unreliable just doesn't make sense.

Breath tests in DWI cases are far more common than blood tests. Breath test machines are usually put in the jails for easy access by police, results are available in minutes, samples are analyzed in an environment completely controlled by police, and cheaper for the police than taking and preserving a blood specimen.  In breath test cases, Texas uses the Intoxilyzer 5000.

Blood tests require more steps and more time: a qualified person must draw the sample in sanitary conditions, the officer must label and package the sample for mailing, have it sent to the "crime" lab, the lab must analyze the sample and notify DPS of the results, and DPS must mail notice of suspension to the accused at his license address.

A hospital blood test has numerous problems, too. Blood tests are the exception in DWI cases, rather than the rule, so detail here will be sparse. Suffice to say that a hospital's emergency room blood test is designed to produce a "quick and dirty" result to give doctors an idea of what they are dealing with, not a result for the technical, precise, and demanding arena of the courtroom.

As you might suspect, breath test shortcuts don't favor the accused. One big difference is that a blood sample is saved and can be retested by the defense for accuracy, but the breath "sample" is literally blown out of a hole in the breath machine. Inexpensive technology is available to capture the sample for later, more accurate testing, but Texas has chosen a state-wide policy of allowing the sample to be "destroyed" in every case.

You might be interested to know a couple more things about the machine. It strictly assumes that your breath and blood have a direct ratio of 2100:1. Human beings' true ratios range from about 1000:1 to over 3000:1. The 2100:1 assumption helps some people and hurts others. Are you willing to take the risk that your result could be inaccurately skewed up by as much as 50%? The machine also assumes your breath temperature to be 34 degrees Celsius, which is about 93 degrees Fahrenheit. If your breath temperature is higher than that, your test result will be higher than your true level.

The manufacturer of the Intoxilyzer 5000 and DPS forbid anyone but law enforcement personnel to inspect and test the machine's accuracy. Truly scientific techniques and methods are generally subjected to open and critical examination and testing by the scientific community. Such a process ensures that the techniques and methods employed are reliable and accurate.  Defense lawyers and experts hired by the defense are resisted at every turn. It's no wonder that even the manufacturer of the machine doesn't warrant the Intoxilyzer 5000 as fit for any particular purpose.

Police often try to get people to take the tests to "prove" innocence. That attitude loses sight of the basic truth that you are innocent unless proven guilty. YOU ARE REQUIRED TO PROVE NOTHING about your innocence. The government has the entire responsibility of proving your guilt.

Be aware that refusing to take the test or failing the test can carry severe consequences. REFUSAL of a test can lead to a suspension of your driver's license (or your privilege to obtain a license, if you don't already have one) for 90 days to 1 year. Also, refusal to take a test is statutorily admissible at your trial to imply that you didn't take the test because you knew you would fail it. On the other hand, FAILING the test (getting a .08 or higher), can result in suspension of at least 60 days. You have a right to a hearing on whether your license should be suspended, and it must be requested as soon as possible.

Driving during a suspension period constitutes a crime commonly called DWLS (Driving While License Suspended). Penalties for DWLS are very similar to the penalties for DWI, including an additional license suspension.

The news isn't all bad. Should a jury or judge find you "not guilty" after a trial, your driving record can be cleared of the suspension, and your arrest can be removed from your criminal record.

Given the unreliability of breath testing and the way Texas has chosen to conduct its breath testing program, I will not advise someone to take a breath test.

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*All answers are for people 21 years or older, do not involve enhancements, are not exclusive, and are limited to Texas.

**This page is for informational purposes ONLY and must not be relied upon as legal advice because it is NOT a substitute for the advice of a qualified attorney, nor does it establish an attorney-client relationship.

Not certified by the Texas Board of Legal Specialization.

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