We Warned Them in June. They Ignored Us. Now 39 More Cases Are Toast.
The BCA did nothing. Now 39 more people face overturned convictions
Yesterday brought more troubling news out of Winona County: 39 DWI cases are being dismissed and convictions vacated because law enforcement used the wrong type of dry gas cylinder in their breath alcohol analyzer for over three months.
If this sounds familiar, it’s because Chuck Ramsay and I literally wrote about this exact error in our peer-reviewed article, Errors in toxicology testing and the need for full discovery, published in Forensic Science International: Synergy, back in June 2025.
The Same Error, Different Counties
Here’s what happened in Winona County: Between June 14 and September 20, 2025, an officer repeatedly used a dry gas cylinder designed for PBT (Preliminary Breath Test) devices in a DMT (DataMaster) breath alcohol analyzer.
Why does this matter?
These cylinders aren’t interchangeable. PBT cylinders are specifically formulated for fuel cell technology, while the DMT analyzer uses infrared spectroscopy.
Using the wrong cylinder type means the calibration check becomes meaningless. You can’t verify accuracy when you’re using the wrong reference standard.
We Warned About This Months Ago
In Section 3.3 of our article published in Forensic Science International: Synergy, Chuck and I documented this exact scenario from a 2023 Minnesota case:
“In 2023, a Minnesota breath alcohol test operator ran a series of evidential breath alcohol tests on the DataMaster DMT, an infrared analyzer, using a type of dry gas reference material intended for use in fuel cell breath alcohol analyzers. Due to the unique characteristics of fuel cell devices, special reference materials are produced with assigned values different from those intended for infrared devices. The use of inappropriate reference material raised questions about the veracity of the test results.”
We categorized this as a “traceability error”; one of eleven types of toxicology errors we identified in our review of forensic toxicology mistakes.
The Pattern That Concerns Us Most
Now, months after our article’s publication, we’re seeing this error pop up in multiple Minnesota counties:
Aitkin County: 73 cases affected (May 2024-May 2025) - discovered by Chuck and I while working on a case
Winona County: 45 cases from the first incident, now 39 more from this latest discovery
Chippewa County: 13 cases affected
Each time, it’s the same fundamental mistake: lack of quality control over the state's reference material.
What Did the BCA Do After We Published This?
Here’s the question that needs to be answered: What did the Minnesota Bureau of Criminal Apprehension do when we published documented evidence of this systematic vulnerability back in June?
Based on the continued emergence of these cases, the answer appears to be: not enough.
Sheriff Ron Ganrude says his department is now “reviewing its policies and making adjustments to make sure cases like these do not happen again.”
They’re limiting access to PBT cylinders to one staff member and DMT cylinder changes to two staff members.
But why did it take another 39 compromised cases before these “adjustments” were made? And why does it fall on the Sheriff’s shoulders? The state crime lab needs to implement better quality controls.
The Real Issue: Reactive vs. Proactive Quality Assurance
This isn’t just about one county or one officer making a mistake. This is about a systemic failure in how forensic laboratories respond to documented vulnerabilities.
When researchers publish peer-reviewed evidence of a specific type of error affecting multiple jurisdictions, laboratories should:
Immediately audit all similar equipment statewide for the same vulnerability
Review all procedures that could lead to the error
Implement preventive measures before more cases are affected
Publicly disclose findings and corrective actions
Instead, what we’re seeing is a reactive approach: wait until defense attorneys discover the problem in individual cases, then address it county by county.
What We Called For in Our Article
Chuck Ramsay and I identified this pattern across all types of toxicology errors.
Here’s what we recommended:
1. Transparency through online discovery portals
Laboratories should provide online access to all validation studies, standard operating procedures, maintenance records, and quality assurance documentation. When systematic errors are discovered, affected cases should be immediately identified and disclosed.
2. Mandatory retention and disclosure of digital data
All calibration records and quality assurance data should be preserved and made available online. This would have allowed immediate identification of all instruments where the wrong cylinder types were used.
3. Independent laboratory accreditation with rigorous oversight
Current accreditation processes aren’t catching these fundamental errors. We need a more robust external review by independent experts.
4. Regular third-party audits
Many of the errors we documented persisted for years before detection. Independent audits could have caught the cylinder issue before it affected hundreds of cases.
The Winona County Response
To their credit, the Winona County Attorney’s Office is doing the right thing now: dismissing pending cases and working with defense attorneys to vacate convictions. Sheriff Ganrude is acknowledging the mistake publicly.
But prevention is always better than cleanup.
Looking Forward (or Backward?)
The most concerning question: How many other Minnesota counties might be experiencing this same error right now?
Without a comprehensive statewide audit of all DMT cylinder installations and Control Change procedures, we have no way to know.
And based on the pattern we’ve seen, the next discovery will likely come not from internal quality controls, but from a defense attorney and their expert reviewing case files months from now.
Chuck and I documented this vulnerability in June, documenting cases that date back to 2023. Multiple counties have now been affected. How many more cases need to be compromised before the BCA implements systematic preventive measures?
The pattern we identified in our research continues: Errors in toxicology testing are almost always discovered by external reviewers, like defense attorneys, whistleblowers, and independent experts.
Until the fundamental dynamic changes, we’ll keep seeing the same preventable errors affecting people’s lives, liberty, and criminal records.
We continue to monitor developments across Minnesota counties. If you have questions about breath testing procedures or cylinder documentation in your case, feel free to reach out. Send your test records to aaron@aaronolson.expert.
Read our full article: Olson, A. and Ramsay, C. (2025). “Errors in toxicology testing and the need for full discovery.” Forensic Science International: Synergy, 11, 100629. [https://doi.org/10.1016/j.fsisyn.2025.100629]
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