Find Michigan DUI Lawyer | Problems with Breath Testing Equipment in Michigan

by baronedefensefirm on March 2, 2011


DataMaster - Michigan's Breath Testing Equipment

If you are arrested for drunk driving in Michigan then you will most likely be asked to submit to a breath test.  The purpose of this test is to determine the amount of alcohol in your body.  The name of the device used in Michigan is the DataMaster.  The majority of the DataMasters in use today were manufactured in either 1993 or 1995.

Like Michigan, Wisconsin’s breath testing equipment is aging.  There is an interesting and alarming recent case involving this aging equipment where it seems that a pair of breath tests was done on a person arrested for drunk driving using an EC-IR fuel cell.  The EC-IR produced results of .224 and .228.  These breath tests were 7 minutes apart and there was a simulator test between them.

The person arrested then asked for his own test and was given a blood draw.  The sample was sent to the Wisconsin State lab and came back a .014. Nobody believed it so they did a confirmatory test at another lab and it also came back a .014.  When it comes to determining bodily alcohol levels, blood testing is thought to be far more reliable than is breath testing.

Now one state lab is pitted against another and everybody just wants to get rid of the problem.  Intoximeter (the manufacturer of the EC-IR) is blaming the blood lab – not surprising – and is refusing to acknowledge that their breath testing device made a mistake.

Everyone involved in Wisconsin appears to be afraid to investigate the issue.  Here are some possible explanations for what happened:

Problem with EC-IR in Wisconsin case might include:

  1. Floating Decimal Point – The breath test results are .224 and .228 while state blood draw hour later is .014. If you just move the decimal point, then one hour earlier (when breath test occurred) the driver could actually have had a .0224 and .0228 breath alcohol reading. This result would comport with the possible parameters of alcohol metabolism.
  2. Problems with chamber temperature.
  3. Contamination.
  4. Software extrapolation (algorithm integration problem ).
  5. High calibration – check simulator solution or dry gas and regulators, true calibration problems.
  6. Software degradation – Software ages and get corrupted with time or self-imposed degradation. This does happen and might have occurred on this unit.
  7. Plunger problems and carryover contamination.

Michigan does not use the EC-IR in the investigation of drunk driving cases, but instead uses the DataMaster.  However, in the list above, the items of greatest concern is that involving the floating decimal problem and the software aging problem.  It is particularly this later issue that may cause problems in Michigan.


DMT Prototype - Set to go in Service in Michigan in Late 2009.

However, it is expected that sometime this year Michigan will replace the aging DataMaster units with a new and improved version called the DMT, an acronym which means “DataMaster Transportable.”  This new breath testing device is expected to be placed into service as soon as July 2009.  This at least will solve the aging software problem.

Currently there are about 260 “old” DataMasters in Michigan.  So far, the state has bought about 140 new DMTs.

In Michigan there are no known cases like the one in Wisconsin.  Many other types of anomalies have been observed, but these anomalies are not supported by a much lower blood test result.


This post was written by...

– who has written 204 posts on Michigan Drunk Driving Lawyers.

Patrick T. Barone is the author on two books on DUI defense including the well respected two volume treatise Defending Drinking Drivers (James Publishing), and The DUI Book – A Citizen’s Guide to Understanding DUI Litigation in America. He is also the author of a monthly DUI defense column for the Criminal Defense Newsletter, published by Michigan’s State Appellate Defender’s Office. Mr. Barone is an adjunct professor at the Thomas M. Cooley Law School where he teaches Drunk Driving Law and Practice. He is also on the faculty of the Criminal Defense Attorney’s of Michigan’s Trial Lawyer’s College where he provides trial skills training to Michigan’s criminal defense practitioners. Mr. Barone lectures nationally on various DUI defense topics, and he has appeared in newspapers, on television and on radio as a drunk driving defense expert. Mr. Barone has been certified as an instructor and practitioner of the Standardized Field Sobriety Tests and has also attended a 24-hour certification course at National Patent Analytical Corporation (the manufacturer of the DataMaster) and has thereby been deemed competent by the manufacturer to operate, perform essential diagnostic verifications and calibration checks on the DataMaster. Mr. Barone is a Sustaining Member of College for DUI Defense. Mr. Barone is the principal and founding member of The Barone Defense Firm, whose practice is limited exclusively to defending drinking drivers. The Firm is headquartered in Birmingham, Michigan.

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