Published on 9/25/2025, 9:42:00 AM
What Does PBT Mean in a Maryland DUI Case?
A Preliminary Breath Test (PBT) is a roadside screening tool police use to help decide whether to arrest you for DUI. In Maryland, you may refuse a PBT without automatic license penalties. PBT results aren't admissible at trial to prove guilt, but officers can use them to establish probable cause. The separate, official test (at the station) has different rules and MVA consequences. Learn the difference below.
What Is a PBT?
A PBT is a handheld breath device used at the roadside to estimate your alcohol level during a DUI stop. It's a screening tool, not the certified evidentiary machine used after arrest. If you're comparing devices and consequences, start here: PBT vs. Breathalyzer.
- Police typically pair the PBT with field sobriety tests (walk-and-turn, one-leg stand, etc.).
- The PBT helps an officer decide whether there's probable cause to arrest.
Do You Have to Take a PBT in Maryland?
No. Maryland drivers may refuse a PBT without triggering the automatic license penalties that attach to refusing the official breath or blood test after arrest. That official test is part of the separate administrative (MVA) track. More on that below.
Key point: PBT refusal is not the same as refusing the official test. If you're deciding what to do at the roadside, read our quick comparison: PBT vs. Breathalyzer.
Are PBT Results Admissible in Court?
No In Maryland, PBT readings aren't admissible at trial to establish you were over the limit or impaired.
PBT vs. the Official Station Test
After arrest, you'll usually be asked to provide a sample on a certified evidentiary device (often called the �Breathalyzer� in casual speech). Refusing that test can trigger MVA consequences such as license suspension and ignition interlock options. Get the practical rundown in our guide: PBT vs. Breathalyzer and the BAC rules in DUI Per Se (.08+).
If you received a refusal or suspension notice, you may be able to contest or modify it at an administrative hearing. Learn the deadlines and options here: MVA Hearings.
Why Police Use PBTs
Officers use PBTs to triage roadside decisions. Typical inputs:
- Driving behavior and stop quality
- Field sobriety performance (see our walkthrough of common tests: Field Sobriety Testing)
- Admissions (for example, �I had two drinks�)
- Odor, speech, balance, eyes
- A quick PBT reading to corroborate impairment before arrest
Remember: the charge matters. Maryland distinguishes DUI vs. DWI, and the State can also proceed on a per se theory if your BAC is .08 or higher (DUI Per Se).
How PBTs Affect Defenses
Even though the PBT doesn't come into trial as proof of BAC, it can influence the probable cause analysis. Effective defenses focus on:
- Stop legality (why you were pulled over)
- Field test administration and environmental or medical factors
- Timeline between driving and testing (absorption or retrograde issues)
- Video vs. narrative inconsistencies
- Device differences: how the PBT and evidentiary test are treated under Maryland law
If a reduction is on the table, your lawyer may aim to move from DUI to DWI, or negotiate PBJ when appropriate. For a practical overview, skim our First-Time DUI FAQ.
FAQs
Q: What does PBT mean?
A: Preliminary Breath Test, a roadside screening tool used during DUI stops.
Q: Do I have to take a PBT in Maryland?
A: No. Refusing a PBT does not trigger automatic license penalties. That's different from refusing the official post-arrest test, which can have MVA consequences. See MVA Hearings.
Q: Can PBT results be used in court?
A: Not to prove guilt. They're generally used to support probable cause for arrest, not as trial evidence of BAC.
Q: What's the difference between a PBT and the Breathalyzer at the station?
A: The PBT is a screening device. The station test is a certified evidentiary test with very different legal consequences. Read PBT vs. Breathalyzer.
Q: If I blew on a PBT and still got arrested, is my case over?
A: No. Many cases turn on how the stop and tests were conducted. A focused defense can target the stop, field tests, and evidentiary testing, and sometimes support a reduction to DWI or PBJ. Compare charge levels here: DUI vs. DWI.
Arrested After a DUI Stop?
Don't go it alone. The Maryland DUI lawyers at FrizWoods challenge stops, testing, and procedures, and work toward reduction, PBJ, or trial.
Questions about your PBT, refusal, or MVA deadlines? Contact us for a free consultation.
Related resources
- DUI vs. DWI
- DUI Per Se � .08 BAC
- Field Sobriety Testing
- PBT vs. Breathalyzer
- MVA Hearings
- First-Time DUI FAQ
Unsure whether to fight the stop, the tests, or both? Contact us and we'll map a step-by-step plan.
