The lights come on behind you. Your stomach drops. What you do in the next few minutes matters — not just for tonight, but potentially for months of court proceedings. This article explains exactly what happens at a Utah DUI traffic stop, what your rights are, and where people make mistakes that come back to hurt them later.
Why You Were Stopped
A police officer needs reasonable suspicion of a traffic violation or other criminal activity to pull you over. Common justifications for a DUI stop include weaving within a lane, crossing the centerline, failing to signal, speeding, expired registration, or a broken taillight. The stop itself does not require suspicion of drunk driving — many DUI arrests begin with a minor traffic infraction.
Once stopped, if the officer observes signs of impairment — bloodshot eyes, the smell of alcohol, slurred speech, an open container — the investigation shifts. What was a simple traffic stop becomes a DUI investigation.
What You Are Required to Do
Utah law requires you to pull over promptly and safely when an officer signals you to stop. You must provide your driver license, vehicle registration, and proof of insurance when asked. These are legal obligations. Refusing to comply with a lawful stop creates additional legal problems that have nothing to do with the underlying DUI investigation.
Beyond those requirements, your obligations are narrow. You do not have a legal obligation to answer questions about where you have been, what you have had to drink, or where you are going.
What You Are Not Required to Do
You have a Fifth Amendment right to remain silent. That right applies on the roadside just as it does anywhere else. You can politely decline to answer questions beyond providing your identifying documents. Something as simple as "I'd prefer not to answer questions without an attorney present" is legally sufficient and legally sound.
This is not about being rude or uncooperative. It is about understanding that roadside statements are almost always used against you, not for you. An officer asking "how much have you had to drink tonight?" is not trying to help you — the answer goes directly into a report and potentially into evidence at trial.
The Portable Breath Test (PBT) Is Different from the Post-Arrest Test
Officers often ask drivers to blow into a handheld breathalyzer at the roadside before any arrest is made. This is called a preliminary breath test or PBT. In Utah, you are generally not required to submit to a roadside PBT. Refusing it is typically not subject to the same automatic license suspension consequences that follow refusal of the post-arrest chemical test.
The post-arrest chemical test — taken at the station or hospital after a formal arrest — is a different matter entirely and carries serious consequences for refusal under Utah's implied consent law. That is covered separately.
What the Officer Is Looking For
From the moment you pull over, the officer is observing and documenting. The contact begins before your window is even down. Officers are trained to note the odor of alcohol or marijuana, your appearance (eyes, skin, clothing), your speech, and how you handle tasks like retrieving your license and registration. All of this goes into the report.
If the officer detects signs of impairment, they will typically ask you to step out of the vehicle. At that point, the investigation moves to its next phase: field sobriety tests.
Field Sobriety Tests: A Separate Decision
Roadside field sobriety tests — the walk-and-turn, one-leg-stand, and horizontal gaze nystagmus test — are not legally required in Utah. Unlike the post-arrest chemical test, there is no automatic license suspension for declining to perform them. They are voluntary, and the results are used exclusively as evidence against you.
Whether to perform them is a real decision with real consequences in either direction. That decision is covered in detail in the next article in this series.
The roadside is not the time to try to talk your way out of a DUI. Explaining that you only had two drinks, that you feel fine, or that you have a high tolerance does not help you. It gives the officer more material for the report and provides the prosecution with more to work with at trial. Stay polite, stay calm, and provide only what is legally required.
If You Are Arrested
If the officer places you under arrest for DUI, do not resist — physically or verbally. Invoke your right to counsel clearly: "I am invoking my right to an attorney." From that point, do not answer substantive questions until you have spoken with a lawyer. You will be transported to a police station or jail facility for booking, and a chemical test will be administered.
The ten-day clock on your driver license hearing also begins running from the date of arrest. That deadline is separate from your criminal case and is covered in detail later in this series.
What to Do After the Stop
Whether you were arrested or released, write down everything you remember as soon as possible — the reason the officer gave for stopping you, what questions were asked, what you said, what tests were requested, and what happened in what order. Memory fades and details matter. This information is valuable to your attorney.
If you were arrested, contact a DUI defense attorney immediately. The criminal case and the driver license proceeding run on separate tracks with separate deadlines, and both require prompt attention.
Arrested for DUI in Utah?
Jim Tily handles DUI defense in Salt Lake County and across Utah. Free consultations. Call now — deadlines start running from the day of your arrest.
(801) 641-0883 Send a MessageThis article is for general informational purposes only and does not constitute legal advice. Laws change and individual circumstances vary. Contact an attorney to discuss your specific situation.