Portable/Preliminary Breath Test. Let’s be clear. The portable breath test (“PBT”) is different from the chemical blood draw or chemical breath test done back at the police station. The chemical test is described and outlined in Utah Code 41-6a-520.
You don’t have to take the PBT. You can refuse to take the PBT without consequence as of 04/2023.
Chemical Testing. You can refuse the chemical blood or breath test also, but you can be charged with an independent crime for refusing it and you lose your license for 18 months upon the first offense. The new criminal code for refusing a chemical breath test is found at 41-6a-520(7). Utah is an implied consent state. Meaning that when you receive your driver’s license, you agree to conduct a chemical test when asked to by a police officer. See Utah Code 41-6a-520.
A portable or preliminary breath test in Utah is a field testing breathalyzer that the officer asks you to use while on-scene. It is not very accurate and not admissible in court.
The PBT is one of many tool law enforcement officers use to determine if they have probable cause to arrest you for a DUI. The PBT in addition to field sobriety testing, smell and your actions are all tools police use to form probable cause to arrest you for a DUI. See this article on what probable cause is.
Refusing the PBT is up to you, but a positive PBT on the roadside is just yet another nail against you as the officer formulates probable cause to arrest you.
No. The roadside portable beath test results are not admissible in court, outside of stating it was taken and a positive result was incurred.
PBT can be used in a courtroom to see if any party in the courtroom has alcohol on their breath. PBTs that were used on roadside and registered low can be used at sentencing advocacy purposes to show the judge your low BAC potential. PBTs can be used at suppression hearings when a court is asked to see if the police officer had probable cause to arrest you or not. PBT are also discussed sometimes at the 10 day driver’s license hearing.
Most people don’t know they can refuse to the PBT and field sobriety testing. It is not a crime to refuse these probable cause tools that police officers rely upon in arresting you for a DUI.
Prior to 07/01/2020 it was not an independent crime to refuse the chemical blood/breath test. It may suspend your driver’s license administratively for 18 months, but it was not a crime to refuse it. 
Since 2020 41-6a-520(7) makes it a crime to refuse the chemical testing. The criminal sentencing for refusing a chemical test are exactly the same as a DUI conviction under Utah Code 41-6a-505. Basically the new law makes the penalties associated with refusing a chemical test the same as a DUI, so you can’t get out of the DUI by refusing.
