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  • David A. Cmelik Law PLC

Is portable breath test really voluntary?


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The PBT, or, preliminary breath screen, is typically the last sobriety test in the field during a Cedar Rapids or Iowa City OWI (DUI) criminal investigation.

While the Horizontal Gaze Nystagmus, Walk and Turn, and One Leg Stand tests are completely voluntary, the PBT is less so. Why is that? Well, officers will advise you that the PBT is your choice as well. But there’s a catch. If you refuse a PBT, the refusal itself may be admissible before the jury on the issue of your intoxication—even though a failing test result would not be. What? I’ll say that again: a preliminary breath test, or, PBT screen test result positive for any amount of alcohol is not admissible on the issue of your guilt before the jury.

The jury can never know your PBT test result as it is inadmissible for the purpose of proving your guilt. The reasons for this are complex but they relate back to when the Iowa Legislature and the Department of Public Safety approved portable breath testing devices decades ago. Calibration errors and the state of the art of technology made them unreliable and the law has treated them as such ever since.

Only alcohol breath tests from the Datamaster DMT devices in law enforcement centers in every Iowa county are considered evidentiary—meaning that your test result in the police station or jail using a device that sits on a desk can be used against you in court. But the PBT test you blow into out on the road cannot.

A PBT test refusal is a contested matter. Prosecutors will argue that a refusal speaks to your state of mind and desire to conceal intoxication and has nothing to do with the technology of the device or the legislative purpose of inadmissibility. Therefore, they will argue that a portable field test refusal should be admissible before the jury.

There's another rub to a PBT refusal that doesn't apply to the physical agility tests. If you refuse a PBT and the officer already believes that he or she has reasonable grounds to believe you are impaired, they will hands-down arrest you on refusal. Now, to be fair, by the time you get to a PBT, there is a good chance you will be arrested whether you provide a PBT over the presumptive limit of intoxication of .08 g ETOH/210 L breath or not.

Many times, officers will say that the PBT is a simply a tool they use to “see whether the impairment I’m seeing is due to alcohol or something else,” a foregone conclusion that you are impaired before the PBT or the more evidentiary DMT. In this way, they improperly turn the PBT into a reverse drug test and assume their conclusion before testing.

However, I’ve heard lore about the occasional test subject who “passed” the field sobriety testing and was allowed to drive away. This type of lore fuels compliance with the tests along with the officer’s typically false narrative that he or she wants to “make sure you’re safe to drive home.” That won’t ever happen if you refuse the PBT—even if it only rarely happens when you consent to a PBT and test below the presumptive level of intoxication in the State of Iowa, which is .08 g ETOH/210 L breath.

Also, make sure you understand that you can be arrested if the officer believes you are impaired regardless of what you test on the PBT and especially if you provide a positive test result for any amount of alcohol. Sometimes, they “gin” up a case against a motorist that they are impaired but from a combination with, or something other than, alcohol—thus their argument that they are ruling alcohol in or out as a source of impairment or partial impairment. The PBT, along with any so-called ARIDE (Advanced Roadside Impairment Driving Enforcement) or DRE (Drug Recognition Expertise) they attempt to summon in support of their investigation, will thus determine whether they request a urine sample at the stationhouse instead of, or in addition to, a Datamaster DMT breath evidentiary breath test.

So when should you refuse to provide a PBT? Well, because PBT refusal carries no administrative sanction to the privilege to operating a motor vehicle, a PBT refusal where you know that you are well over the presumptive level of intoxication is not wrong. It will guarantee your arrest but won’t hurt your privilege to operate a motor vehicle in the State of Iowa.

But understand that there is a harder decision to be made at the stationhouse or jail—where the evidentiary Datamaster DMT machine will be waiting along with the consequences to a driver’s license for test failure or refusal. While a PBT refusal carries no additional sanction to your privilege to operate a motor vehicle in the State of Iowa, this is not the case with the evidentiary Datamaster DMT back at the stationhouse—usually the second request to blow. A DMT test—the desk blow— refusal typically doubles the revocation of a privilege to operate a motor vehicle.

That’s a different question. For now, suffice it to say that by the time you are asked to blow into a portable screening device, or, PBT, it’s a difficult, personal choice for which there may be no good answer. Because you’re reading this now, instead of likely before you had to make that choice, chances are good the die is cast.

If you or a loved one have been arrested for Operating While Under the Influence (OWI) in Cedar Rapids, Iowa City, or other Iowa community or county, contact David A. Cmelik Law PLC for a free initial consultation. Remember that a blog is not legal advice and that sending unsolicited information to a lawyer over the Internet does not establish an attorney-client relationship.

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