Challenging the Breath Test (Part III)

BAC DataMaster

I once attended a seminar where an attorney argued that there were many things which “mirrored” ethyl alcohol, thereby interfering with the ability of the breath testing machine to distinguish between “real” alcohol (ethyl) and “false” alcohol (acetone). The interfering substance, acetone, is a natrually occuring by-product of the human body and is common in diabetics, dieters and persons coming into contact with household paints.  What’s more there was some pretty solid science presented to support this argument. WOW!

Well, after studying the BAC DataMaster I am sorry to say that this method is very limited as a defense.  First, while acetone is plentiful, it’s property as an interferrant is blunted by a machine using two infrared “filters.”  The infra-red beam is shot through a breath sample.  The existence of acetone or alcohol creates a diminishment in the energy which is read by a solenoid and changed into volts.  The change in volts is then converted via the machines software into the BAC reading.

Alcohol has an IR signature, i.e. wavelengths in which the energy is absorbed.  Acetone, as an inteferrent is present at only one of these wavelengths.  The machines use two of these wavelengths and compare the results.  Thus is acetone is present the machine will note the difference and is supposed to reflect that fact.

For the limited number of defendants for whom this argument will work, it is a powerful defense.  For the majority however, it is an easily refutable and dangerous gambit.  The client would be better served by a frontal attack on the machine.

Attorney Charles M. Rowland is a certified operator of the BAC DataMaster and earned his certificate by attending 24 hours of training at National Patent Systems, Mansfield, Ohio.