Breath Testing Machines


The breath testing equipment used by law enforcement has certain parameters within which it operates.  In certain circumstances these machines direct the operator to take specific steps in order to facilitate a valid reading.  The DataMaster cdm, for example will generate a breath strip with “codes” on it if a test is not completed.

Frequently,  when a person is deemed a “refusal” by  law enforcement, the officer does not bother to retain the breath strip printout and simply notes in the police report that the individual did not blow hard enough or was attempting to “fool “the machine.  A close review of the instrument usage log can provide valuable information to defend a refusal allegation both in court and at the Admin Per Se hearing with the DMV.

If an individual blows into a DataMaster and the machine generates a code “V” the operator is instructed on the printout that the last air sample was “invalid” and to “wait 15 minutes” until attempting a new test.  The instrument usage log will contain the time of the first test, the code and the time of the subsequent test.  If there is not a 15 minute period between the two tests it can be successfully argued that the officer, not the person attempting to complete the test, is responsible for the failure to complete the test.

A breath testing instrument, as prosecutors and hearing officers like to refer to it, is simply a machine.  If the operator of the machine does not follow the manufacturer’s directions and uses the machine outside the parameters for which it was designed, it is not the fault of the individual attempting to complete the test if the machine does not generate rate a result.

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