Just because someone is given a breath test or a blood test, does not mean the government has a slam-dunk case against them.

There are a number of challenges that can be made to invalidate these tests or to minimize the usefulness of these tests.

The police who administer the tests must comply with specific legal standards. The machines that are used in these tests must be accurate and trustworthy.

Some of the issues our DWI defense attorneys review when criminal charges are brought are:

What Did The Chemical Test Show?

Police officers use chemical tests to determine a driver’s blood alcohol content (BAC). Most tests examine the driver’s breath or blood.

Some tests examine the driver’s urine or saliva. In all states now, an adult driver whose BAC is .08% or more can be found guilty of Driving While Intoxicated (DWI). This means that if the test was lower than .08%, the chemical test cannot be used to prove guilt.

For commercial truck drivers, the BAC limit is .04. For drivers under 21 years of age, the standard is even lower. In most cases, if a person can defeat the BAC test, they can win their case.

Were The Necessary Warnings Given?

Officers typically have a duty to explain the consequences for failing to take a chemical test – such as an automatic suspension of a driver’s license.

If the officers failed to properly warn the driver, they may be able to challenge the results of the test.

Was The Test Properly Administered?

The test machines must be regularly inspected and properly calibrated. There are also specific requirements on how the tests should be administered.

There are often forensic chemists or experts who can challenge the accuracy of the test. Some of the things they review are:

  • What foods the client took before the test was administered.
  • Whether the client took any mediations that might have affected the results.
  • How long it was between the consumption of the food, medications, or any alcohol the client took and the time of the test. It takes time for the body to absorb alcohol which can affect the BAC results. The key question is what was your BAC when you were driving, not hours later.

It is also possible to challenge whether the person who gave the test had the authority to give the test and the chain of custody of the test.

The chain of custody requires showing what happened to the breath or blood test between the time the test was given and the time of the trial.

Call Scott M. Brown and Associates Today

If you or a loved one was charged with a DWI offense, an experienced Texas DWI lawyer can help.

Convictions can mean jail time, substantial fees and penalties, suspension of your driver’s license, and increased insurance premiums.

At Scott M. Brown and Associates, our lawyers have a reputation for strong advocacy. To learn more, please contact us for a 1-on-1 consultation at 979-849-8526 or contact us online.