If a defendant provided a breath sample, the DWI conviction rate is significantly higher. But that's primarily because of the way the law is written, and not because Breathalyzers are bulletproof. In Texas, if the defendant's BAC level was above the legal limit, the defendant could be guilty as a matter of law.
If officers have probable cause, they can demand that DWI suspects provide chemical breath or blood samples which determine their Blood Alcohol Content. If the BAC level is above the legal limit, which is usually .08, the defendant might be guilty as a matter of law. About 80 percent of DWI suspects provide chemical samples.
Whether or not the defendant provides a chemical sample, the Field Sobriety Tests are important in DWI cases.
Frequently, intoxication, or lack thereof, is the only issue in a DWI case. However, even if the defendant was drunk as a skunk, Parker County prosecutors might be unable to establish guilt beyond a reasonable doubt.
Months of intense court supervision is not for everyone. That's especially true if the defendant has issues accepting authority or has problems getting to certain places at certain times. For these and other reasons, an increasing number of DWI defendants choose a brief jail sentence over a lengthy period of probation.
Most states legalized DWI checkpoints in the 1990s. Generally, these checkpoints are legal, as long as they meet certain requirements. One such requirement is specific legal authorization from the state's legislature.
Drivers' license suspension is perhaps the worst collateral effect of a DWI. However, contrary to popular myth, arrest-related drivers' license suspension is neither automatic nor mandatory. That's assuming the defendant requests an Administrative License Revocation hearing. At the ALR hearing, the state must prove specific facts to impose license suspension.
The conviction rate in DWI chemical test cases is about twice as high as the conviction rate in non-test cases. Even still, only about 20 percent of DWI defendants refuse to provide a breath or blood sample.
During the early years of the DWI crackdown, Texas lawmakers amended Section 49.04 of the Texas Penal Code. Under these new amendments, people who have a BCA above the legal limit are intoxicated as a matter of law.
Researchers at the University of Texas at Dallas have developed a saliva test which determines the level of marijuana in a person's system.