Portable Breath Tests (PBTs) are simple hand held contraptions that certain law enforcement agencies carry and use to determine if a suspect has consumed alcohol. The PBT uses fuel cell technology to convert detected alcohol into an alleged level alcohol in the suspect’s blood stream.
When we’re talking about DWI, it is important to know that in Texas, results of PBT devices are not admissible in a court of law. PBTs are NOT EVIDENTIARY breath tests. The only evidentiary breath test in Texas is the Intoxylizer 5000 that is provided by suspects AFTER they have already been arrested for DWI, in the event they agree to provide a sample. PBTs have not been approved as reliable by the Department of Public Safety, the state legislature, or the state courts. A police officer that uses a PBT can only testify as to whether the PBT showed the presence of alcohol and can only consider the result when determining whether probable cause to arrest a suspect for DWI exists.
In terms of Driving Under the Influence by a Minor (DUI), the PBT becomes the most useful for law enforcement. As you may know, it is illegal for anyone under the age of 21 to consume any alcohol in Texas. It is also illegal for minors to consume any alcohol and then drive. If law enforcement believes an underage suspect is drinking, the PBT would give the officer evidence that he could bring into court showing the presence of alcohol on the minor’s breath.
Like the Intoxylizer, I believe it to be sound legal advice to never blow into a PBT. Refusal of a PBT may lead to an arrest for something, but the refusal itself is not a criminal offense and there are no drivers’ license consequences for refusing to take a PBT. In the Austin area, very few law enforcement agencies even carry the PBT, only DPS (ironically) uses them consistently in this area.