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Breath/Blood Testing in Drunken Driving Cases

Driving while intoxicated or under the influence of alcohol can lead to serious criminal charges. You can even face charges for driving with other intoxicants, such as drugs, in your system.

If you are pulled over, law enforcement officials usually give you a series of tests to determine if you are impaired while operating a vehicle. They can perform field tests or breath tests during the traffic stop to understand your blood alcohol level. Any chemical testing on blood or urine needs to be completed at a station.

Common Drunk Driver Tests for Police Departments

Most state drunk driving laws permit a Breathalyzer or a blood test to be performed to measure the blood alcohol concentration (BAC) level of a suspected drunk driver.

Breath Testing

The Breathalyzer is performed when the suspected drunk driver blows into a mechanical machine. The resulting reading will measure the amount of blood alcohol content found in the person’s breath or lungs.

Field Testing

An officer might ask you to perform tasks, such as following a light with your eyes, to see any influence of drugs or alcohol. If you can’t follow simple directions, walk a straight line, follow along with your eyes, or think straight, it can show driver impairment. These various methods are known as field sobriety tests (FST).

Blood or Urine Testing

Blood or urine samples can be tested at the police station. A blood sample may be drawn when:

  • The police can’t obtain a Breathalyzer reading
  • An independent test, such as a blood sample, is performed at the request of the suspect (depending upon the state’s law)

However, there are usually statutory guidelines that will govern the circumstances in which a blood sample can be withdrawn.

Example Drunk Driving Case for Independent Testing

The person — called the defendant — was pulled over by a police officer for suspicion of drunk driving. A breath test was administered and resulted in a reading of 0.16%. This is twice the legal limit in this jurisdiction.

Under a state law in which the drunk driving arrest occurred, law enforcement officers must advise the defendant they may also undergo independent testing.

The arresting officer advised the defendant of their legal right to an independent test, including a blood sample. The defendant believed the results of a Breathalyzer are unreliable and requested an independent blood sample.

Independent Testing: Talk To Your Attorney First

There are other circumstances where a drunk driving suspect may request an independent blood sample. Likewise, many state laws also permit blood samples to be taken without the defendant’s express consent.

If you encounter a drunk driving situation, you should advise the law enforcement officer that you wish to consult with a drunk driving defense attorney before submission. Many state laws will permit you to consult with a lawyer before submission, but only within a short time after an arrest.

Implied Consent Law for Drivers

All states have enacted an implied consent law. This means the law requires you to submit to a chemical test to measure your blood alcohol concentration (BAC) level. This is only required if the police stop your vehicle because they have a reasonable belief that you are driving drunk.

These laws are called implied consent laws because driving is a privilege and not a right from the government’s perspective. If you do anything wrong, you can lose your driving privilege in the eyes of the law.

What Constitutes a Refusal of a Chemical Test?

You and other drivers agree to submit to a chemical test at law enforcement’s request as a condition to the implied consent privilege. An officer can request this at any time during driving while intoxicated investigations.

If you refused to take a breathalyzer or provide a sample of your blood, most states would revoke or suspend your driving privileges by the Department of Motor Vehicle (DMV).

Drunk Driving Investigations: Know Your Rights

Criminal defense attorneys may find law enforcement officers:

  • Failed to properly inform a suspected drunk driver about their rights
  • Misunderstood or do not possess sufficient knowledge of their state’s implied consent laws and their effects of the defendant’s decision of whether or not to submit to a test

An example is a defendant stopped for driving while intoxicated by a state trooper. They are not sure if they are under the legal limit at this moment. The trooper informs the defendant that their license would be suspended for six months if they fail to submit to the Breathalyzer.

However, it requires a mandatory one-year license suspension under state law when the suspect refuses to submit to a drunk driving test. Not knowing their alcohol content level makes them worried about breath testing devices. Because the defendant believes their licenses will only be suspended by the DMV for six months, they refuse to take the test.

“I Refuse To Take the Test”

If the words “I refuse to take the test” are said, it is affirmative that a refusal has occurred. However, a refusal is not always so clear-cut. It is best to consult with an attorney if you have been charged with a drug impairment or drunk driving-related offense or refused to submit to a test.

If you or a loved one has recently been arrested and refused to submit to a Breathalyzer or blood test, consult with a qualified drunk driving attorney today. They can discuss your legal rights and what available legal defenses can be employed to challenge your case.

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