Hundreds of DWI cases have been affected by faulty breathalyzers

The Minnesota Bureau of Criminal Apprehension is asking law enforcement agencies statewide to verify the accuracy of their breathalyzers after discovering calibration errors that made hundreds of DWI breath tests inadmissible in court.

This issue first came to light in Aitkin County, where defense attorney Chuck Ramsey found that an officer failed to properly calibrate a DataMaster device despite documents claiming otherwise. This finding led to the dismissal of several DWI cases and the invalidation of 73 breath tests.

BCA later confirmed similar issues with devices in Winona, Chippewa, Hennepin and Olmsted counties, including more than 140 potentially affected cases in the latter two jurisdictions. The agency has suspended use of all 220 DataMaster tools across Minnesota until each tool is inspected and verified.

Going forward, BCA says only its employees will install and maintain the gas cylinders used to calibrate the devices, in an effort to prevent future errors.