Utah DUI Breath Test & Blood Test Information

The two primary ways to measure the amount of alcohol in someone’s blood are breath testing and blood testing. Utah police officers use two methods of breath testing—portable breath tests (PBTs) and Breathalyzer® or Intoxilyzer machines. Typically, during a DUI investigation, after asking you to perform field sobriety tests, the officer will ask you to take a portable breath test. This test will show whether there is any alcohol in your breath and give the officer a general indication of the amount. If you are arrested for DUI, you will be asked to take a more accurate breath test, called a Breathalyzer or an Intoxilyzer. If an officer cannot test your breath for some reason, or you refuse to take the test, an officer may perform a blood test, either with your consent, or by getting a warrant.

Portable Breath Tests (PBT)

The Portable Breath Test (PBT) is a small handheld device which can give a police officer a general idea of how much alcohol someone has consumed. However, because portable breath tests are not 100% accurate, and they are designed to give an unverified reading of someone’s blood alcohol content (BAC), the specific results of a portable breath test are not admissible in court. A police officer can testify, however, about whether the result is positive or negative. Because a court cannot rely on a portable breath test to show whether someone is over the legal limit, a portable breath test alone is not enough to prove someone is driving under the influence. An officer must also obtain a breathalyzer test or blood test.

Breathalyzer® / Intoxilyzer Machines

If you fail the field sobriety tests (FSTs) and the portable breath test (PBT) shows positive for alcohol, you will probably be arrested for DUI. Once you are arrested, the police officer will usually take you back to the police station to take a breathalyzer/Intoxilyzer test to get a more accurate reading of your blood alcohol content.

A breathalyzer is a machine that is used to measure a person’s blood alcohol content (BAC) by measuring the amount of alcohol vapor contained in that person’s lungs. There are multiple types of “Breathalyzer” machines. The breath testing machines used by Utah police are called the Intoxilyzer 5000 and the Intoxilyzer 8000. These machines use spectrometer (light-based) instruments to measure alcohol vapor in lungs, then the machines estimate how much alcohol must be in the blood to produce that much vapor.

Because Intoxilyzer machines do not test the blood directly, and must use calculations based on averages, they are not completely accurate for many people. If you weigh less than average of if you blew into the machine for longer than average, then the Intoxilyzer will probably show a higher amount of alcohol than is actually in your blood. Intoxilyzer machines may also give incorrect readings for people who have diabetes, acid reflux, or other medical conditions. Other things, like alcohol residue in the mouth or radio waves may also interfere with the readings. Or, if the machine itself is not calibrated correctly, its readings may not be accurate.

A dedicated criminal defense attorney can examine the facts of your case and determine whether there are problems with your breathalyzer results.

Utah Blood Testing

A blood test is the most accurate type of DUI test used by Utah law enforcement. Usually, an officer will not administer a blood test unless someone is unable or unwilling to take a Breathalyzer test. When an officer does a blood test for alcohol, a police technician will take a certain amount of blood, mark and seal it in a vial, and send it to the lab to be tested. Blood tests can take several weeks to several months to be processed. Although no science is 100% accurate, the courts view most blood test results as extremely reliable.

Utah law requires police to follow several procedures in order to assure that DUI blood tests are not tainted. If the police do not follow the correct procedures for drawing the blood, marking the blood, transporting the blood, and testing the blood, then the government may be prohibited from using those results in court.

DUI Lawyers at Intermountain Legal

Intermountain Legal has experienced DUI attorneys who have handled thousands of DUI cases in Salt Lake City and all of Northern Utah. When we take a case, our attorneys immediately gather the evidence against you to determine the strength of your case. If you have a strong defense, we have the DUI trial experience to win your case at trial. Our firm has a former prosecutor who trained directly with police officers on how to perform Utah field sobriety tests. From this experience, he learned the most common mistakes made by police officers in the field and how to expose those mistakes in trial.

If the case is solid against you, we will negotiate to minimize the consequences and find the best solution for you. Because we have experience on the other side, we know what judges and prosecutors are looking for, and we will help you make the best decisions every step of the way.

Contact Our Utah Criminal Defense Attorneys

To contact our DUI lawyers for a free consultation, call 801-990-4200 or fill out our quick contact form.

Additional Information on Breath and Blood Tests:

Why Breath Tests of Blood-Alcohol Don’t Work by Michael P. Hlastala, Ph.D.