Forensic experts question reliability of breathalyzer used by Minnesota law enforcement agencies |

Forensic experts question reliability of breathalyzer used by Minnesota law enforcement agencies

Updated: July 14, 2019 10:34 PM

A 5 EYEWITNESS NEWS investigation has found testimony of forensic experts questioning the reliability of the breathalyzer used by more than 200 Minnesota law enforcement agencies.

KSTP also found court rulings issued by four judges in three different counties ordering the manufacturer of the DataMaster DMT Breathalyzer, Intoximeter, Inc., to give the breathalyzer software to defense attorneys for "further testing" to ensure it's reliable.

Defense attorney, Chuck Ramsay, told KSTP he's found the DataMaster DMT, on some occasions, will give what he called "false-positive" results and will sometimes round breath tests up rather than down as it is supposed to do.

"It can report a result higher than it actually is," said Ramsay.  "And, in more and more cases we are finding these results are not valid, reliable or accurate."

Ramsay said the false positives are created by the DataMaster when it fails to properly "kick out interceptors" which are supposed to be rejected by the machine which then leads to a reading of the driver's breath alcohol rather than blood alcohol level.

More from KSTP:

Lakeville police arrest 3 for DUI with children in vehicles within 12-hour time frame

Woman pleads guilty to DWI, endangering child

Troopers arrest more than 200 for DWIs over Fourth of July holiday

"So, it is designed to measure the amount of alcohol in the driver's blood, but it is not doing that," said Ramsay.  "In some cases, it is measuring the alcohol in their stomach from the driver's last drink which significantly changes the result."

Forensic Criminalist, Jan Semenoff, has testified in more than 150 DUI cases and reviewed Ramsay's findings.  He is not affiliated with Ramsay's law firm, but did agree with the research material Ramsay presented in court.

"What Mr. Ramsay has found would lead me to believe that people are being convicted on bad evidence," said Semenoff. "Not insufficient evidence, but bad evidence."

Semenoff told KSTP he agrees with the orders by judges in Hennepin, Scott and Ramsey Counties that the company Intoximeter should turn over the DataMaster's software for further testing to make sure it is working properly.

"If the test results are being inflated, or false positives are not being adequately identified, then you got a situation where the breath testing is being performed in a substandard manner and that's not reliable forensic testing in any way, shape, or form," said Semenoff.

Semenoff said the issue is very significant and needs resolution because, based on his review of the evidence, the DataMaster's questionable readings are leading to charges and DUI convictions which are suspect.

"Based on any of this evidence, people in Minnesota have been wrongly convicted," said Semenoff.

Intoximeter, based in St. Louis, Missouri, declined KSTP's request for an interview and a company employee said, "We do not participate in these kinds of things."

The BCA also declined to comment on camera, but did issue a statement supporting its decision to have a contract with Intoximeter for the use of the DataMaster DMT.

"The allegations Mr. Ramsay makes are False. The devices provide accurate results, and we welcome the opportunity to address any challenges in court. The BCA's internationally accredited calibration laboratory provides evidential breath test instruments to over 200 law enforcement agencies throughout the state. The results provided by those instruments are reliable and admissible."

The BCA stated that it has not turned over the breathalyzer's software because they, "do not possess the source code."

Connect with KSTP

Join the conversation on our social media platforms. Share your comments on our Facebook, Instagram, and Twitter pages.


Jay Kolls

Copyright 2019 - KSTP-TV, LLC A Hubbard Broadcasting Company

5 victims injured in Dinkytown shooting, Minneapolis police investigating

MDH reports 5 new COVID-19 deaths, 132 new cases

Police ID victim after body parts found in Minneapolis; public help sought

Minneapolis man beats the odds to compete in Grandma's Marathon for 42nd time

Woman found dead in Robbinsdale, 1 in custody