When a subject is questioned regarding an OWI, he is often offered a preliminary breath test (PBT) by the officer. Based in part on the results of this test, the officer will make his decision to whether charge the subject with OWI.
As mentioned in other posts, the PBT cannot be used at trial for evidence of intoxication. But what about when the results are favorable, and what happens when the information comes into trial “on accident?”
The basis for excluding the PBT from trial is based on statute. Iowa Code ยง321J.5 provides in part,
“The results of this preliminary screening test may be used for the purpose of deciding whether an arrest should be made or whether to request a chemical test authorized in this chapter, but shall not be used in any court action except to provide that a chemical test was properly requested pursuant to this chapter.”
To gain further understanding of the specifics of this law we must look to the caselaw. State v. Massick, 511 N.W.2d 384, 388 (Iowa 1994) solidifies the fact that the results are not admissible. State v. Deshaw, 404 N.W.2d 156, 158 (Iowa 1987) holds that it is reversible error for the officer to testify to the results while on the stand. However, evidence that a defendant submitted to the test is admissible, so long as no reference is made to the results, as outlined in Gavlock v. Coleman, 493 N.W.2d 94, 96 (Iowa App. 1992).
Now, what happens when the defendant agrees to give up his right to keep this information out of trial, and instead wishes to enter the evidence to prove his innocence? Well, the caselaw proves that the results cannot be used for any purpose. In State v. Iowa Dist. Court for Johnson County, 630 N.W.2d 838 (Iowa 2001), Iowa City’s hometown court was overruled when the judge considered the results of the PBT when granting a deferred judgment. The Iowa Supreme Court stated, “It is apparent here that the district court was partialy persuaded by the lower PBT to grant a deferred judgment…clearly this decision is contrary to section 321J.5.”
Therefore, do not rely on the results of the PBT to haunt you or save you in court. Its only purpose is to help the officer determine if an arrest needs to be made.