Preliminary Breath Tests (PBTs)

This blog is a continuation of the drunk driving series from last week’s post.  This week, we will discuss Preliminary Breath Tests (PBTs).
Again, in the state of Michigan, a person must not operate a vehicle if he or she “has an alcohol content of 0.08 grams or more per 100 milliliters of blood, per 210 liters of breath, or per 67 milliliters of urine” or if he or she is under the influence of alcohol.  To be under the influence of alcohol means that because of drinking alcohol, the individual’s ability to operate a motor vehicle in a normal manner was substantially lessened.
If an officer reasonably believes a person’s ability to operate a vehicle was affected by the consumption of alcohol, the person must submit to a PBT upon request.  PBTs are taken on the side of the road.  Typically, they are done after field sobriety tests were administered.  (See previous blog post on Field Sobriety Test)   PBTs, like field sobriety tests, are used by officers to help establish probable cause that someone was driving under the influence.
If an individual refuses to take a PBT, there are consequences.  Refusal to submit to a PBT may result in a civil infraction, which comes with a fine. However, there are no consequences to an individual’s driver’s license for refusing to submit to a PBT, such as points, restrictions on driving privileges, or driver responsibility fees.  This is different from the chemical test.  Should an individual refuse a chemical test there are consequences regarding the license, I will submit a blog on this also.
PBTs are not admissible into trial in the government’s case in chief.  There are three limited situations in which the PBT results are admissible:

  1. May be admitted to help the court to decide whether an arrest was valid;
  2. The defendant can offer the results as evidence of his blood alcohol content (BAC) to rebut testimony that came out on cross of a defense witness that the defendant’s BAC was higher at the time of the charged offense than when a chemical test was administered; or
  3. The prosecutor may introduce the results to rebut testimony that came out on cross of a prosecution’s witness that is offered to prove the defendant’s BAC was lower at the time of the charged offense than when the chemical test was later administered.

If you or someone you know has been charged with a drinking and driving offense, feel free to contact our office.


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