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What's the Difference Between a Blood Test and a Breathalyzer?


Understanding How Blood Alcohol Level Is Tested

When being pulled over for suspicion of driving while under the influence of alcohol or drugs, the police in the State of Nevada have several different options for testing whether someone is intoxicated or under the influence.

These methods can range from a field sobriety test to blood alcohol content testing through breath or blood testing.

Blood Testing

Of the ways to test blood alcohol content, blood testing is the most invasive way that the police can use to obtain proof that the driver was operating the vehicle while under the influence of alcohol or drugs.

It is important that the individual who is suspected of driving under the influence be aware that the police are not immediately guaranteed the right to test that person’s blood alcohol concentration via a blood test. If someone has never been convicted of a DUI previously, he or she should first be given the choice to take a breath test.

If this is the person’s second or third DUI arrest in seven years, a blood test is not optional. If the police want a blood test, the person must submit to the blood test under Nevada’s implied consent law.

Blood can only be drawn by a doctor, a licensed physician’s assistant, a registered nurse, EMT, or phlebotomist. The person has the right to request that the blood test be taken at a location of his or her choosing. However, the individual making this request is then responsible for any additional costs of the test.

If the person refuses to submit to a blood test in a DUI investigation, the law does allow the police officer to use as much force as is necessary to get that blood sample, which includes three blood samples within a five-hour time period after the arrest.

Blood Test Evidence in a DUI Trial

Like other DUI tests, certain procedures must be followed during the blood draw to ensure that the evidence is allowed during the trial. By having the evidence questioned, the accused may be able to get the charges dropped or at least reduced successfully.

The blood test results can be challenged if one of the following occurs:

  • the person was harmed during the test

  • the equipment was broken

  • the test was taken too long after the arrest

  • it was not done by a qualified medical professional

  • the blood test results were not stored properly

  • the blood was contaminated after the fact

A defense attorney can assist in helping to prepare the proper defense in the event the blood test results are at all in question.

Breath Test

As opposed to an actual blood test, a breath test via a “breathalyzer” is used to test the alcohol content of a person’s blood but through his or her breath.

Officers in the State of Nevada use the Intoxilyzer 500EN to perform breathalyzer tests.

This method of testing is not as invasive as blood testing, although the results are not as strong as an actual blood test.

If the person pulled over refuses to submit to a breath test, he or she may then be brought in for a physical blood draw.

When it comes to disputing the results of a breath test, the results are also considered much less reliable. If any question exists as to whether the results are valid, a DUI defense attorney can assist in preparing the proper defense to fight these results.

The following could allow a breathalyzer test to be disputed:

  • if it is found that the internal settings of the breathalyzer machine were not proper

  • if the measurements of the machine were not properly set up before the device was used

  • if the breathalyzer needed repairs or had been repaired recently

  • whether the machine was or was not in good working order

  • if any glitches or malfunctions appeared in the test results

  • human error

Since a breathalyzer requires a police officer to administer it, human error will almost always come into question. If it is found that the person who administered the test did not have the correct training or his or her credentials were not up-to-date, the results could also be disputed.

Contact Us Today!

If you have been arrested for a DUI while visiting Nevada and believe the blood alcohol content test results in your case should be in question, it is important you contact the Hill Firm today. We can meet with you to discuss your rights and all potential legal consequences from your arrest. Contact us today at (702) 848-5000.

Dan Hill