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Reasons DWI Cases Are Dismissed



DWI, or driving while under the influence of alcohol or a drug, is a serious charge that can have long-range implications for anyone convicted of this offense. With many attorneys specializing in DWI defense, however, there are a variety of reasons why DWI cases end up being dismissed at or before trial.

Legality of the Stop

Although relatively rare, there are instances where law enforcement may have illegally stopped your vehicle or lacked probable cause to do so. Your vehicle can only be stopped for the following reasons:

  • Violation of a traffic law
  • Erratic or irregular driving
  • Equipment violation
  • DWI checkpoint
  • Fits description of a stolen vehicle or one involved in a crime

Random stops are illegal as are stops based on racial profiling or any other reason unrelated to breaking the law.

Probable Cause for a Breath Test

Another reason for dismissing a DWI is the lack of probable cause for the officer to request a breath test. If you were stopped for speeding and denied drinking any alcohol, you may be asked to perform certain balance or field sobriety tests if the officer suspects you were drinking. But you are not obligated to perform these tests, and few sober people can perform these accurately. If you refuse, the officer is left with few, if any other, factors to base the request that you take a breath test other than your driving conduct and your demeanor.

You can refuse to take a breath or chemical test, but you risk losing your license for at least one year. At a license suspension hearing that you must request, you have to argue and demonstrate the following:

  • Invalid stop
  • Lack of probable cause to request a breath or chemical test
  • The breath or chemical test results were invalid
  • You had a legitimate reason for refusing the breath or chemical test
  • Lack of probable cause that you were under the influence

Challenging the Breath or Chemical Test

Most reasons for getting a DWI dismissed are from successful challenges to the accuracy or validity of the breath or chemical test. A skilled DWI lawyer knows how an Intoxilyzer or breathalyzer operates and can contest the protocol used in administering the test as well as the mechanics of the machine itself. If the machine was improperly calibrated or the manufacturer refused to turn over its source code, a court could rule that the test results are inadmissible. A person’s medical condition could also affect the accuracy of any test results.

Similarly, blood and urine tests that look for certain drugs, including alcohol, must be shown to have followed a chain of evidence; samples must have been taken according to strict protocols.

Contest Your License Suspension

Anytime you are charged with a DWI, your driver’s license is subject to suspension in a proceeding separate from the criminal charges. If you fail to challenge your suspension at an administrative hearing, you will lose your driving privileges immediately even if you are later found not guilty or your case is dismissed at or before trial on your criminal charges.

If you are successful in the administrative proceeding to regain your license, there is a chance that the prosecutor in your criminal case may not pursue the criminal case against you and will dismiss your case.