Drunk Driving Defense – Beating The BAC Datamaster Machine in Michigan

Beating the BAC Machine

The typical drunk driving stop has the following scenario: Police officer has the driver perform a field sobriety test and a preliminary breath test (PBT). If the officer claims that the driver failed then there likely will be an arrest and a transport back to the station where a breath sample will be taken for analysis by the BAC Datamaster machine. However, there are strict regulations regarding the administration of the Datamaster testing. If these rules are not followed the alcohol testing result should be inadmissible in court.

1 – BAC Database Machine Calibration

The machine must be properly calibrated weekly. A Datamaster log is kept by the police. Upon inspection, it is occasionally found to be returning results beyond the tolerance allowed. Therefore, such results should not be admissible in court. Since the initial PBT result is not admissible, the only evidence would then be the officer’s oral description of the driver’s alleged intoxication. Most prosecutors would not want to proceed with such week evidence of intoxication.

2 – Police Observation for 15 Minutes Before BAC Administration

The police officer administering the Datamaster test must observe you continuously for 15 minutes. The reason for the rule is to insure that the driver has not put anything in their mouth nor possibly have regurgitated anything – which could possibly distort the results. Frequently the arresting officer is in a rush and will administer the test as soon as the driver arrives at the police station. Matching up time from the “dashcam” and “booking” video will help determine if the requiredminimum observation time has been met.

3 – Challenging Old or Unreliable BAC Database Machines

The final legal challenge to the admission of Datamaster results would be the reliability of the Datamaster machine itself. The technology employed is decades old and makes assumptions and uses techniques that may not be valid in every situation. Additionally, the state wants to purchase the cheapest machines that they can – often with some security features stripped out to lower costs. Experts can be hired to successfully attack the validity of the Datamaster machine.