Breath, Blood & Urine Tests

Houston DWI Attorneys: Challenging DWI Tests

When you are suspected to be driving while intoxicated (DWI) by alcohol consumption, a law enforcement officer may ask you to submit to a breath, blood, or urine test. The officer may also have you complete field sobriety tests, which are physical tests designed to show physical awareness and agility that is supposed to indicate sobriety or intoxication. Though you can refuse to take a breath, blood, or urine test when requested by an officer, this will result in an automatic license suspension. This suspension is up to twice the length of the suspension you would face if you had been convicted of DWI.

Understanding more about DWI tests and what to do if you are pulled over by a law enforcement officer can help you make the right choices in the face of DWI charges. In addition to reviewing the information here, please feel free to contact a Houston DWI lawyer at our firm at any time to discuss your unique situation, questions, and concerns.

The three different types of chemical tests that are commonly used after a DWI arrest are:

  • Breath Tests – Using an Intoxilyzer, a breath test involves blowing into a device that measures the alcohol in your breath to determine your blood alcohol concentration.
  • Blood Tests – This test is conducted using a blood sample, which is analyzed for the presence and concentration of alcohol. This often considered the most accurate test.
  • Urine Tests – Usually only performed for DWI cases involving suspected drug use, this test involves taking and analyzing a sample of a driver’s urine.

Problems with the Breathalyzer

The most commonly performed BAC test is the breath test, also known as the “breathalyzer.” In this test, an officer has the suspect take a deep breath and blow into a device that will read the amount of alcohol in the person’s breath. This device is delicate, however, and must be properly calibrated before each use in order to produce a valid reading. The way a person breathes into the device can also affect the integrity of the reading, such whether or not they blew into the device for a long enough period of time for a reading to be taken. A person’s health may even affect their reading, such as if they have a medical condition such as acid reflux, or even if they have a simple fever. The margin of error can be surprisingly large at times due to these necessary procedures.

I failed a breath test. Can a Houston DWI lawyer help?

The tests described above can be the evidence that puts you in jail for DWI. They, can all be administered or evaluated improperly, however, resulting in an incorrect charge. There are countless instances in which these tests were dismissed due to flaws and errors in everything from device maintenance to test evaluation. We know how to fight for your rights – let us help you with your DWI. You don’t have to face harsh penalties, jail time, fines, probation and other consequences related to a DWI charge.
If you have been charged with DWI, it is in your best interests to speak immediately with a lawyer who has experience successfully handling such cases in Texas. Contact a Houston DWI attorney at The Martinez Law Firm today to see how we can help you.