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What Is The Portable Breath Test? Why Is It Used?


A portable breath test (PBT) is an alcohol sensor that officers carry with them. They will ask a driver to blow into in and it will give a quick indication of whether or not the driver has ingested alcohol. There are certain standards that are required for a portable breath test. More than anything else, I see the portable breath tests being used as a way to get a driver to submit to other forms of testing so that they can ultimately get them to submit to the breathalyzer at the station. There are a lot of issues with the portable breath tests, particularly in regards to maintenance. There are also a lot of factors that need to be considered when an officer gives a portable breath test. A lawyer should be aware of these factors in order to effectively cross-examine someone about the use of a PBT.

What Is The Difference Between The PBT And The Evidential Breath Test At The Station?

The evidential breath test or breathalyzer at the station is more specifically tuned and is operated by someone who is certified to do so. It is a more precise way of testing a person’s blood alcohol content than is the PBT.

Is The PBT A Voluntary Or A Mandatory Requirement In Missouri?

If you refuse to submit to the PBT, then your license will be in jeopardy. This is especially true if you refuse to submit to the official breathalyzer at the station.

What Happens If Someone Refuses The PBT?

It’s subjective. If you refuse the PBT, the officer may say that you refused the field sobriety testing. As a result, he could write that you refused to comply and your license would be suspended. In order to have your license reinstated, you would have to go through an administrative hearing.

Are There Any Factors That Can Influence The Result Of The PBT?

There are multiple factors that can influence the result of the PBT, including how it was stored, when it was last calibrated and what the base level is. It is necessary to establish a base level before asking someone to blow into the machine. If a base level has not been established, then there’s no way to know what is really being measured or how to interpret the results. An officer also has to be certified in order to use the PBT. A lawyer should be aware of all of these factors when handling these cases.

Is The PBT Admissible In Court?

The PBT is admissible to establish an officer’s probable cause that the person had been drinking, but it is not admissible as evidence to show whether or not the person was actually intoxicated. The breathalyzer at the station is used establish whether or not someone was intoxicated.

Additional Information On PBT In Missouri

Most people think that the results of the PBT are conclusive, but they are not. I believe that the reliability of the PBT is purely subjective from the officer’s point of view. If a police officer stops you, he is instantly going to want to issue a ticket. But just because an officer charges you with DWI does not mean that you should not fight it. You have rights that need to be defended, and that’s what we do here at the Jimerson Law Firm. We establish that people have rights and that they are not going to be trampled on just because that’s what an officer wants to do.

For more information on Portable Breath Test In Missouri, a free initial consultation is your next best step. Get the information and legal answers you are seeking by calling (314) 786-3536 today.

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