A PBT stands for Preliminary Breath Test in DWI cases. Some people call it a portable breath test. Minnesota statutes refer to it as a preliminary screening test. However you slice it, it means the same thing. It is a handheld device that cops use as part of their field sobriety testing in DWIs. In Minnesota, the officer must have sufficient cause to use a PBT during field sobriety testing. Meaning, they cannot just jump to it right away without any just cause.
In State v. Juncewski, the Minnesota Supreme Court reasoned that reasonable articulable suspicion of a DWI is needed to request a PBT. PBTs are the only field sobriety tests where the legislature states a specific standard for invoking the test. The legislature seemed to recognize that requesting a PBT is more intrusive than other field sobriety tests, such as the one-leg-stand test, the walk-and-turn test, and the horizontal gaze nystagmus (HGN) test. Often, officers will ask someone to take a PBT after they put the driver through the other field sobriety tests. Thus, building reasonable articulable suspicion to get to the PBT.
Importantly, the PBT is not a test that prosecutors can use to charge someone with a DWI in court. That is the evidentiary test taken at the police station or local jail in breath test cases. Evidentiary urine tests are rarely requested in DWI cases anymore, but when they are, they can take those at the police department. For evidentiary blood test cases, those are sometimes administered at a hospital. In urine and blood test cases, officers will seek a warrant first.
In breath test cases, after an officer asks someone to take a PBT, depending on the results of the test, the cop will arrest the driver on suspicion of DWI. The officer will then ask the driver to take a second breath test at the police department or local jail. Drivers can often be confused about the second request for a breath test and not understand why they are being asked to take another one. The crucial point is that the test at the station is the evidentiary test. That is the one that prosecutors can use to charge someone with testing .08 or more.
Results from a PBT are only admissible in court in limited circumstances. One circumstance is in DWI Refusal cases. In those matters, the prosecutor can submit evidence of the PBT result to build probable cause for the arrest of DWI and the request to take an evidentiary test. In pre-trial litigation, the prosecution may also use the results of the PBT if your attorney challenges probable cause for arrest. But, if you end up in a criminal trial by judge or jury, then your defense lawyer should be making sure that the results of the PBT are not admitted as evidence in a DWI trial for testing .08 or more. A main issue is that PBTs are not scientifically reliable tests. While officers may have them calibrated and up to speed on servicing, the science behind them are not good enough to support charges in court for testing at or above the legal limit.
PBTs are also often used in minor consumption cases, underage drink and drive matters, and juvenile court proceedings. The tests can also be used in some civil actions and license reinstatement matters. In underage drink and drive cases, the prosecution will argue that any positive result on a PBT violates the law. The penalties can include a license suspension for thirty days on a first-time offense and one hundred and eighty days for a second offense.