The Different Types of DUI Testing That Law Enforcement May Use By Jason Trumpler, P.C. on April 13, 2014

The Different Types of DUI Testing That Law Enforcement May UseWhen you are pulled over and suspected of drunk driving, the law enforcement officer has a number of ways of assessing your sobriety. Each of these methods has their flaws, however, which is why a number of drunk driving charges are disputed. A DWI lawyer is crucial if you want successful legal outcomes following a drunk driving arrest.

Right now, our lawyers would like to take a few moments to consider the different methods of testing that are available to legal professional when attempting to assess a person's level of intoxication.

Field Sobriety Tests

Field sobriety tests refer to non-scientific physical tasks that drivers are asked to perform in order to assess the driver's coordination and motor skills. Conducted after the driver is pulled over, these actions include:

  • Standing on one leg
  • Walking a straight line
  • Touching the nose with arms out to the sides
  • Monitoring horizontal eye movements

Since these field tests are non-scientific, they can be flawed and failure of a test is no proof of intoxication. This is particularly true if the driver is nervous or stressed simply by the fact of being pulled over.

Blood Tests for Blood Alcohol Concentration (BAC)

Blood tests that assess intoxication involve analyzing the BAC of a driver's blood. The blood sample is taken at the station and assessed there.

While these blood tests are far more scientific than the field sobriety test, they can be quite flawed. Blood samples can be contaminated or tainted, and final measures of BAC may be off due to human error.

Urine Tests for Blood Alcohol Concentration (BAC)

Urine tests are similar to blood testing for BAC. In these cases, a urine sample is taken from the driver rather than a blood sample.

In addition to contamination and human error in the testing process, the time when the urine sample is provided will have an affect on BAC. If a person has not emptied his or her bladder in a while, the urine sample may contain excess alcohol that does not match the driver's actual lower BAC at the time of arrest.

Breath Tests for Blood Alcohol Concentration (BAC)

Breath tests are commonly used to assess the BAC of drivers, and the tests can be administered out in the field. This involves the use of a breathalyzer. The driver blows into a tube attached to the breathalyzer, which provides an estimate of the driver's BAC.

The readings of a breathalyzer test are not always an accurate assessment of BAC since the presence of other substances in the mouth can affect the overall quality of results. In addition, mechanical failures and improper calibration of the breathalyzer can affect the numbers.

How Our Legal Team Can Assess Flaws in Sobriety Testing

A DWI defense lawyer will carefully examine the circumstances of your arrest and sobriety testing, seeking out flaws that are related to human error and mechanical error. If improprieties are discovered, this may be grounds for throwing out your case. Similarly, the circumstances of the initial traffic stop may be worth questioning.

Learn More About Your Legal Options Following a DWI Conviction

If you or a loved one has been charged with drunk driving, it's important that you get the legal team at The Law Offices of Jason Trumpler on your side. To schedule a legal consultation, be sure to contact our Austin, Texas criminal defense lawyers today. We will answer all of your questions and concerns in great detail so that you can make well-informed choices with regard to your legal options.

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Jason Trumpler

The Law Offices of Jason Trumpler

Jason Trumpler has handled thousands of criminal cases over nearly 20 years. He is a current or past member of several national, state, and local legal associations, including:

  • American Bar Association
  • Austin Bar Association
  • Williamson County Bar Association
  • National College for DUI Defense®
  • Texas Criminal Defense Lawyers' Association
  • National Association of Criminal Defense Lawyers
  • Austin Criminal Defense Lawyers Association
  • DUI Defense Lawyers Association

Contact our firm online or call us at (512) 457-5200 for a free case review.

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