cedar rapids / iowa city criminal defense

Law enforcement officers in Cedar Rapids, Iowa, and Linn County frequently arrest subjects for OWI before they consent to, or, refuse the Datamaster DMT breath test at May’s Island or the Marion Police Department. The reason for this is unclear. I recently cross-examined an NHTSA instructor about whether they would “unarrest” someone if they blew zeroes and he said no. So, the Datamaster DMT—even though it is the most accurate and reliable piece of evidence—becomes the least important to law enforcement in this jurisdiction. 

Why does law enforcement make an OWI arrest before they have the most valuable piece of evidence--the Datamaster DMT test? 

by David Cmelik

In Iowa, an officer may detain and require a motorist to choose between consenting to or refusing a Datamaster DMT breath test at the jail, sheriff, or police station. This is called “implied consent” because every licensed driver impliedly consents to a breath test if an officer has reasonable grounds to believe the motorist is intoxicated. The penalty is revocation for a longer period than if a Datamaster DMT test subject exceeds the statutorily presumptive level of intoxication in Iowa, which is .08 grams per 210 L breath or 100 mL blood.


What does this mean? Well, it means that the officer not only believes he or she has “reasonable grounds” to invoke implied consent by the time the SFST phase of OWI (DUI or DWI) detection is finished, but it also means that they believe they have probable cause to make the arrest before they even get a breath sample that is admissible before the jury.

That’s because the preliminary breath test, or, PBT, is not admissible in jury trial under Iowa law. But the Datamaster result is admissible.


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Source: NHTSA DWI Training Manual

In an Iowa prosecution for OWI (DUI), an officer may detain and require a motorist to choose between consenting to or refusing the Datmaster DMT breath test if the officer has reasonable grounds to believe the motorist is intoxicated.

Not infrequently, law enforcement officers tell test subjects that the PBT is a gauge to determine whether the impairment they are “seeing” is caused by alcohol or another substance. By the time they get to the PBT, they believe they have reasonable grounds to believe the test subject is intoxicated—and under the law before the officer requests a PBT they must have such reasonable grounds—but they just don’t know what is causing it, whether it is alcohol, drugs, or a combination of both. I find this law enforcement reasoning specious and conclusory. The Datamaster DMT test is the accepted, certified, and only breath test admissible in a jury trial. Why would an officer arrest somebody before they had all the evidence in their investigation?

If you or a loved one has been arrested for OWI (DUI) in the State of Iowa, please contact David A. Cmelik Law PLC at 319-389-1889 or www.daclawfirm.com for a free initial consultation today.


However, please understand that a blog is not legal advice and that no attorney-client relationship is established by sending unsolicited information to an attorney over the Internet.