Datamaster Michigan Challenge the Results at Trial - Machine Must be tested, calibrated and working properly or the results will be suppressed

In Michigan the Datamaster machine must be maintained and tested properly in order for it to work properly. The machine determines the fate of tens of thousands of people in Michigan each year, and the machine can’t be treated like your car.

Sticking with the car analogy, law enforcement must always rotate their tires, get scheduled oil changes and always be operating within the most stringent guidelines; essentially getting the maximum gas mileage and performance at all times. If there is a lapse in these guidelines then the test is not reliable, and should be suppressed.

In Michigan, the rules say a class II, IIIA, IIIB or IVB operator must verify every machine on weekly basis using a vapor solution provided by Michigan State Police or using a compressed alcohol gas device that delivers exactly .080 grams of alcohol per 210 liters of vapor. Based on this deliverance, the machine MUST record a result of .076 to .084. Recent case law has ruled that the weekly compliance rule will not automatically suppress the result, but rather it will factor into the weight of the evidence for a judge or jury to determine.

When I get a case, I order the Datamaster logs, and see how the machine was testing before and after my client’s test was performed. Courts have ruled that attack of the logs is permissible and the other test results are admissible as a factor for a judge or jury to consider.
Along with the weekly test, the Datamaster needs to be inspected and verified for accuracy and cleanliness every 120 days by a class IVB operator or a representative from the manufacturer.
If the rules were not followed, or the machine is providing a number outside of the range then it should be attacked. You have two swings at this issue; pre-trial motion requesting that the judge suppress the results, and/or at trial where you can challenge the weight of the results, but they’d be admitted for a judge or jury to hear.

These techniques may require an expert to educate a judge or jury on what weight if any should be attributed to the results. In addition to the overall weight, it may be possible to use the results to one’s advantage.

If I am working on a case where my client recorded a 0.08 or even 0.09 on the Datamaster, and after looking at the logs, the machine is “testing high” at 0.084, we know the machine is turning the 0.08 into a higher number, which helps me argue that it’s possible, if not likely that my client actually could have blown a 0.076, but was only elevated by the margin of error allowed by the machine.

Finally, another method I like to point out to a jury is the machine being tested with a 0.08 solution. That’s probably a good idea for a case where my client blew a 0.08, as the jury knows that number could actually be 0.076 or 0.084, but if my client allegedly blew a 0.18, the machine was not tested for accuracy for what my client actually blew. This is like hitting the popcorn button on your microwave for everything. Would you hit the popcorn button to reheat iced cold chicken? No, and that’s how we attack the test result.