Is Iowa DUI breath test mandatory?

Is an Iowa DUI breath test mandatory? In Iowa, the criminal drunk driving statute is Iowa Code § 321J.2, which is entitled Operating While Intoxicated and also references Operating While Under the Influence.

There are a number of ways that law enforcement can investigation and prosecutors can craft their indictment for this criminal offense. The most common is by proving that the defendant has a breath alcohol content (“BrAC”) over the presumptive level of intoxication using a Datamaster DMT evidentiary breath test machine located at any one of over 100 law enforcement agencies.

Part of how officers go about this is introductory screening. They want to know the timeline for a driver's activities before operation, including point of departure and destination. This is especially helpful if a motorist describes their activities as having been social drinking either at a friend's house, a bar, or restaurant. They will look for bar wristbands or hand stamps. The officer will ask about quantity of alcohol the driver has consumed. These questions usually result in a request for voluntary standardized field sobriety testing, including the Horizontal Gaze Nystagmus, Walk and Turn, and One Leg Stand tests. Officers will follow up these divided attention and physical agility tests with a portable, or, preliminary breath screen, called a PBT. It's important to note that the portable breath test is one of a battery of field tests. It does not affect a motorist's driver's license and it cannot be offered on the issue of intoxication before the jury.

After all of these field tests, if an officer believes the sum total observations demonstrate so-called "Reasonable Grounds" to conclude the driver has operated a motor vehicle under the influence, the officer may invoke implied consent and request further chemical testing using more reliable machines either at the station house or hospital.

The breath testing machines at law enforcement centers are annually certified by the Iowa Department of Public Safety to be accurate as to breath alcohol within .004 g ETOH/210 L breath or five percent, whichever is greater. As such, Iowa criminal law recognizes that a breath test timely requested, correctly advised, and properly administered is presumptive evidence of intoxication at jury trial.

This presumption obviates the need for the prosecution to prove the science of the black box that requires test subjects to blow into a tube and prints out a number. This number is the test subject’s breath, and, therefore, equivalent blood, alcohol level within two hours of operation.

So is the test voluntary? Upon reasonable ground that a motorist is operating a motor vehicle under the influence, an officer may invoke something called “implied consent,” a procedure located at Iowa Code § 321J.6. This procedure allows an officer to temporarily detain a DUI suspect and transport them to a law enforcement center for an implied consent advisory, telephone calls to inform that consent, and, ultimately, the more evidentiary Datamaster DMT test.

A subject who drives on Iowa’s highways, streets, and roads is said to have impliedly consented to this process in exchange for that privilege. He or she can withdraw that consent to waive a Constitutional requirement for a warranted search of their breath, blood, or urine. But in so doing, their privilege to operate a motor vehicle is doubly sanctioned than if they consent to a test and provide a sample over the presumptive level of intoxication.

So is the test voluntary? Yes and no. It feels coerced—and it is—by this grand bargain regarding the privilege to operate a motor vehicle. But law enforcement, prosecutors, and the courts have repeatedly stated that the exchange is legal.

Law enforcement can also take a different tack and just obtain a warrant for breath, blood, or urine. They need not waste time with the implied consent procedure. If they obtain a warrant, the test is mandatory.

If you have been arrested for an Iowa DUI—called Operating While Intoxicated or Operating While Under the Influence here—contact us for an initial consultation.