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  • Writer's pictureDavid A. Cmelik Law PLC

Multiple breathalyzer errors Jan '22


There have been 46 evidentiary Cedar Rapids DUI Datamaster DMT breath tests in 2022 so far. Of those 46 attempts, only 37 produced actual test results. Because the DMT breath test runs two tests on the same breath sample, the average of the first test was .139556 g ETOH/210 L breath and the average for the second test was .139194 g ETOH/210 L breath.


Interestingly, there were several errors in the operation of the three drunk driving breath machines assigned to Cedar Rapids. Two of those machines are assigned to the Linn County Correctional Center and one is assigned to the Marion Police Department.


On January 1, 2022, Datamaster DMT serial number 100225 threw a radio frequency interference, or, RFI code. This was 15 minutes after the same officer used 145806 and obtained a .000 g ETOH/210 L breath test result. An RFI error code indicates that there is significant radio interference around the machine. The Iowa Department of Public Safety Datamaster DMT breath test manual indicates that the operator should ensure that there are no wireless microphones or walkie-talkie radios placed near the machines to interfere with the operation of the machine.


On January 5, 2022, Datamaster DMT Serial Number 145806 threw an error code related to so-called “external calibration,” called a “standard out of range error.” With this code, the Iowa Department of Public Safety Datamaster DMT operator’s manual instructs that the machine draws a sample from a disposable dry ethanol tank. The machine expects a certain result with those dry ethanol tanks and if the machine actually tests at something lower or higher than the expected result by over .004 g ETOH/210 L breath or five perecent—whichever is greater, the machine will throw a “standard out of range” error.


The machine instructions indicate that the Department of Public Safety protocol is to restart the test. If the standard out of range error persists, the manual urges testing with a different Datmaster DMT machine.


On January 9, there were two “blank errors” within six minutes of one another with a single officer and again using the same machine on January 13 with the same officer.


According to the Iowa Department of Public Safety Datamaster DMT manual, similar to an “ambient air fail,” “blank errors” can result when there is a “strong presence of alcohol near the instrument.” The manual recommends that the operator properly ventilate the area and restart the test. If the error persists, the manual recommends that the operator start a new test with a different machine.


Four times during the month, officers obtained INCOMPLETE error codes using Datamaster DMT 145806. The DMT manual indicates that the DMT will not record results from an incomplete test. The graph that usually prints out with the test result receipt cannot be used to determine a test result.


There are protocols in place for officers to recover from these errors and it is important to review the discovery, including written reports, boilerplate forms, and recorded media to determine whether the officers followed those protocols.


If you are searching for an attorney to explore your best options in a Cedar Rapids drunk driving prosecution, or, DUI, case—called Operating While Intoxicated, or, OWI, in Iowa—contact us for a free initial consultation.



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