Datamaster DMT Non-Radio Interference

Because every officer in Oakland County uses the Datamaster DMT in their drunk driving investigations, understanding the various issues that routinely come up with it is vital to a successful cross examination of the officer.  One such issue is when the machine indicates that it believes that there is "interference" in the breath test sample.  What this means is that the Datamaster DMT machine believes that the sample breath blown into the machine contains a substance other than alcohol.

There are all sorts of things that could interfere with the test.  Saliva, stomach contents, and many other things could find their way into the breath test machine.  When we see interference printed on the ticket, we believe it is a major red flag to the accuracy of the test.  The remedy we generally advocate to the jury is that the officer should have obtained a blood draw because there was something wrong with the machine.

Datamaster DMT Invalid Sample

As has been discussed throughout our help center, the Datamaster DMT breath test machine is capable of diagnosing issues as the happen during a breath test.  One thing that frequently happens is when the Datamaster DMT results page prints out "invalid sample."  According to the Datamaster DMT manual, the invalid sample warning happens when  the machine recognizes a negative-going slope or alcohol concentration during the delivery of the breath sample.  What this means in layman terms is that the breath sample passing through the machine is registering an abnormal result.  What this generally means is that there could be issues with mouth alcohol.  If this statement continues to register, the officer should test the suspect on a different Datamaster DMT machine.

Datamaster DMT Radio Interference

Although Oakland County officers will testify that the Datamaster DMT is an infallible device, the simple fact is that it has issues just like any other scientific machine.  One issue that comes up is with radio frequencies affecting the results of the breath test.  This is a common occurrence because most officers wear their radios on their belts while administering the alcohol great test.

The Datamaster can sometimes recognize this effect taking place, and it will in response print out on the ticket the term "radio interference". Radio interference refers to the detection of excessive radio frequency energy.  This is generally caused by transmissions from handheld radios or vehicle microphones being used near the Datamaster DMT.  

We have seen this effect in action and have talked off the record with officers who feel that the new Datamaster machines are much more sensitive to radio frequencies and have resulted in issues with the breath test.


Strange Datamaster DMT Results

One great argument in Oakland County operating while intoxicated cases is when the Datamaster DMT result has something strange printed out on the ticket.  For example, we have seen the term "interference detected" on multiple tests since the new machine came out.  In fact, drunk driving trial lawyer Jim Amberg recently obtained a not guilty in a .16 blood alcohol case because the officer didn't follow the rules when this result prints out on the ticket.

There are many different issues that can come up with the Datamaster DMT, such as the term "invalid sample," "ambient fail," and "radio interference."  These error messages should signal to the officer administering the test that something is wrong with the machine.  Yet it is incredible how often officers simply continue or are satisfied with the these error plagued tests.

Although officers seem to be ok when the check engine light of the Datamaster DMT comes on, we are not and more importantly, juries are not.  Knowing what to look for and what each of these error messages mean is an important part of successfully winning a drunk driving trial. 

Mouth Alcohol Affecting the Breath Test

A great defense that our drunk driving trial lawyers have used with great success in Oakland County is to argue that the defendant had alcohol in their mouth when they blew into the Datamaster DMT machine.  This argument is far from far-fetched as most of us have probably experienced the feeling that you have thrown-up into your mouth.  Not to be disgusting, but when that happens, you can taste the contents of your stomach.  When you consume alcohol and this happens, the reason why you can taste your last beer is because your last beer is actually coming back up into your mouth.  And when there is alcohol in your mouth, there's a good chance that the result of the breath test machine is not correct.

This phenomenon is so important that the Michigan State Police have taken numerous protective measures in the Administrative Rules in order to prevent this from happening.  The Administrative Rules require that officers actually sit there and watch the suspect for fifteen minutes prior to the administration of the breath test.  If the suspect regurgitates, sticks something in their mouth, or if the officer can smell alcohol, then they are required to clear the mouth and restart the observation period.  As the officers will testify at trial, the reason for this is that if alcohol enters the mouth, then the Datamaster DMT can be inaccurate.

Drunk driving trial lawyer Jim Amberg recently had a hung jury in the 48th District Court before Judge Baron where Jim's client blew a .12 on the Datamaster DMT.  However, in watching the video of the stop, Jim noticed that his client had complained about a cheese pizza he had ate prior to driving home from the bar.  After a tough trial with a very skilled prosecutor, Jim was able to convince multiple jurors that the cheese that was stuck in his client's throat caused the breath test machine to be off.  The jury then was unable to reach a verdict and the prosecutor eventually offered Jim's client a disorderly person.

Preliminary Breath Testing

In most drunk driving cases in Oakland County, officers will administer a preliminary breath test on the side of the road prior to arresting somebody suspected of drinking and driving.  This test is for the most part prohibited from being used at trial and its sole purpose in obtaining the test is so the officer can create probable cause to arrest.  

Many times we see that the preliminary breath test, or PBT, gives a different blood alcohol level than the subsequent Datamaster or blood test.  There are trials in which we have been successful in actually admitting the PBT to show the difference between the scores of the various tests.  This is especially helpful if the PBT is much lower than the subsequent alcohol test.

There are also times you can challenge the validity of the arrest if the PBT was not administered properly.  PBT administration is governed by the Administrative Rules and are promulgated by the State Police.  Rules such as the officer establishing that the suspect has not placed anything in their mouth, regurgitated, or smoked with the fifteen minutes prior to the taking of the test come into play when arguing that the officer lacked the probable cause to arrest.  

Uncertainty in Blood Testing

A major shift in how the Michigan State Lab reports alcohol blood test results has recently occurred due to the efforts of our fellow criminal defense colleagues in pressing the lab to testify about what the error rates are in blood testing.  No scientific test is perfect and there is always a margin of error.  In the context of a blood test, the Michigan State Lab now reports the uncertainty level of a blood draw.  What this boils down to is that the lab offers a number which represents how far off the test could be and still considered valid, along with a  percentage, which represents the lab's prediction for how many times out of a thousand that they would expect the result of the blood test to be in the range.

How this works when we deal with these situations is that the client will have a blood draw of a .09.  The Lab will then provide in their report a range of a .02.  Also, a confidence level of 99.7% is given.  What this means is that the forensic scientist from the lab is 99.7% sure that the blood alcohol level tested is somewhere between a .07 to a .11.  And the forensic scientist also believes that in three out of every thousand blood draws they've tested, the result they found is not within that range.  Given the fact that these blood testers have tested hundreds of thousands of blood samples, the amount of blood draws that are completely incorrect is stunning.

Drunk driving trial lawyer Jim Amberg likens these error rates to playing Russian roulette with somebody's freedom.  And that argument has resulted in favorable verdicts for his clients. 

How Blood Vials are Received at the Michigan State Lab

An important part of a successful blood test challenge in an Oakland County operating while intoxicated case is to dig deep into how the blood vials came into the possession of the blood tester who ultimately tests the blood in question.

The first issue is to look at what was going on with the weather at the time the blood kit containing the blood sample was sent in the mail.  A filled blood vial sitting in a hot mail truck for days is going to have an effect on the blood.  Same thing goes as we all know living in Michigan when the temperature goes low in the middle of winter.  Freezing something is going to effect it, an example of which is freezing food, it's never as good as when it's fresh.

The second issue is when the blood kit is actually received by the Michigan State lab.  There is a person who works at the lab that takes all of the kits apart and places the vials into a giant refrigerator that contains hundreds of vials of blood.  This person could see a blood tube with some issues and simply shake it up and nobody would ever know because the prosecutors of Oakland County never call that person as a witness.  Many times the representative of the State Lab doesn't even know who dealt with the blood sample.  This is a great challenge that we have been successful with at operating while intoxicated jury trials in the various courts of Oakland County.

Alcohol is Created Naturally in the Vial Defense

One of the greatest defenses Amberg & Amberg attorney Jim Amberg has ever argued in the context of fighting the validity of a blood draw is to challenge what the effect on a blood test is when the various anticoagulants and preservatives are not present in the vial or when they are not properly mixed.  On one occassion, Jim recalls conducting an Oakland County jury trial in the Clarkston court where the arresting officer was adamant that nothing was in the vials, "he made sure of it."  Not knowing what had been testified to, the forensic scientist from the State Lab then testified that if the powders were not present, then alcohol could be created naturally through the process of blood decaying.  The jury was out five minutes and came back with a not guilty verdict on a high blood alcohol content superdrunk driving case.

The science behind this argument is that if the various powders are not present in the vacuum seal tubes provided in the Michigan State Lab kit which all Michigan officers use, then when alcohol decomposes in the tube, alcohol is a byproduct of that decomposition process.  This effect can happen even if the powders are in the vial if the person drawing the blood doesn't properly mix the vial once the blood is placed in the tube.

If the forensic scientist from the lab testifies that the tubes always have the powders, Jim is quick to point out that the lab doesn't test for the presence of these powders, even though they have the capability to do so.  Additionally, the State scientists have no knowledge of where the tubes come from or whether they are even manufactured in the United States.  Would you trust a Chinese blood vial when it's your freedom on the line?

Challenging the Blood Test

Nothing intimidates so called drunk driving lawyers more than a blood test result.  For reasons we don't understand, lawyers will see a blood alcohol result over the legal limit resulting from a blood draw, and simply tell their clients that they have no chance.  Quite to the contrary, we have won many trials simply by successfully challenging the validity of the test.

The first issues that we are extremely familiar with is how the blood draw was performed, who performed the draw, what was their experience, and where did the draw take place.  Any issues with that must be scrutinized in front of the jury.  The next issue is where did the blood drawer get the needle, was it sanitized in alcohol?  We find that most blood drawers have no idea what the needles they used were sterilized in.

Another attack on the blood draw is to determine whether the Oakland County officer checked to see the expiration date of the blood test kit.  All of the blood test kits used in Michigan and in Oakland County have an expiration date for a very specific reason, which is that the vacuum sealed tubes and their contents, much like a gallon of milk, lose their quality after a period of time.  As Amberg & Amberg attorney Jim Amberg always asks the jury at closing arguments: "would you drink a gallon of milk that was sitting in your fridge for six months?"

A powerful attack aimed at the self-named Michigan State forensic scientists is always in play in blood draw cases which is what happens when the vacuum seal tubes do not contain anticoagulant and preservative powders that should be present.  The forensic scientist must testify that if the powders are not present, then alcohol can be created naturally in the vial!

There are many more case specific challenges to the blood draw that we have used with great success before Oakland County juries.  The one thing we never do is tell our clients that the blood test cannot be beat!

The Datamaster DMT

The Datamaster DMT is the newest breath test machine that in the past year has been adopted by all of the various police departments in Oakland County.  The Datamaster DMT is the machine used when a suspect is brought back to test to see what their blood alcohol level is.  These results are admissible in Oakland County courts that handle drunk driving cases.

The Datamaster DMT is the replacement machine for the long-used original Datamaster machine.  In about 2009, the Datamaster DMT machine was presented to the various Oakland County police departments as the predecessor to the original Datamaster machine.  After a lengthy time, our attorneys started to see the newer DMT machines being used in Oakland County around the beginning of 2014.  Now, every drunk driving case we handle in Oakland County which deals with a breath test is performed on the DMT machine.


There are numerous differences between the original machine and the DMT.  The most noticable difference between the machines is that the DMT interface is much more "high tech" and gives officers and operators many more options to choose from when administering the test.  Another major difference is in how the DMT tests itself for errors.  The original Datamaster machine required an operator to run an independent sample of a .08 alcohol solution through the machine.  The DMT instead contains its own internal gas tank with a sample that is in theory a .08.  The human element is taken out of it, which should cause concerns to anybody whose freedom is on the line.