Over the past several years, no issue in Minnesota DWI defense litigation has produced more consistent victories than the so-called “source code issue.”
Since 2017, Ramsay Law Firm has repeatedly challenged the State’s refusal to disclose the software operating Minnesota’s DataMaster DMT breath-testing instruments. While many courts have denied source-code discovery requests, courts outside Hennepin County have ordered the state to turn over the source code with surprising frequency. Based on our experience litigating these cases across Minnesota, we estimate that courts grant some form of relief on the DataMaster DMT source code issue roughly 15% of the time outside Hennepin County. In practical terms, that means either the State voluntarily dismisses the breath-test result or the court excludes it.
We believe that number may soon improve.
In a recent Hennepin County DWI case, the Court appears to have taken a serious interest in the DataMaster DMT source code issue and, more importantly, appears to understand it. That matters because source-code litigation often turns on whether courts appreciate two critically important points.
First, drivers charged with DWI are not required to prove something is wrong with the source code before obtaining discovery. If we could prove the source code was defective, we would not be requesting discovery; we would be demanding suppression.
Second, Minnesota’s original 2010 contract for these breath-test instruments appears to require the manufacturer to disclose the DataMaster DMT source code upon a court order, even after the contract expired.
Why DataMaster DMT Source Code Matters in Minnesota DWI Cases
More than a decade ago, Minnesota courts confronted a difficult reality during the Intoxilyzer 5000EN litigation: breath-testing software can contain significant errors that routine calibration and quality-control procedures fail to detect.
Ramsay Law Firm helped lead that litigation.
Today, Minnesota courts once again face the same issue, this time involving the State’s current breath-testing instrument, the DataMaster DMT.
Our firm recently moved to compel disclosure of the DataMaster DMT source code in a pending criminal case. Several other DWI defense firms have since joined the effort. The State responded by filing affidavits from Bureau of Criminal Apprehension (“BCA”) employees asserting that source-code review is unnecessary because:
- the DataMaster DMT has been validated,
- the calibration laboratory holds accreditation,
- and the BCA performs various quality-control procedures.
Minnesota heard many of these same assurances during the earlier Intoxilyzer source-code litigation.
And yet, source code review still uncovered substantial software problems.
Most importantly, calibration checks did not reveal those errors. Source-code review did.
Minnesota Intoxilyzer Litigation Revealed Problems Calibration Did Not Find
Many lawyers and judges remember the Intoxilyzer 5000EN litigation. Some have forgotten why Minnesota courts ordered source-code disclosure in the first place.
The issue never centered on whether the BCA acted in good faith.
The issue centered on whether calibration procedures and internal validation studies adequately substitute for independent review of the software that operates the breath-test instrument.
They do not.
During the earlier Minnesota Intoxilyzer litigation, source-code review reportedly uncovered numerous software issues, including problems affecting how the instrument classified breath samples as acceptable or deficient. In some instances, the instrument reportedly classified drivers as having provided deficient samples, effectively “refusals,” even though their alcohol concentration fell below the legal limit.
Those discoveries mattered for a simple reason: ordinary operational testing did not uncover them.
That history matters today because the State once again asks courts to rely primarily on agency assurances instead of permitting limited expert review of the DataMaster DMT source code.
Accreditation Does Not Replace DataMaster DMT Source-Code Review
One of the BCA affidavits also overstates the significance of accreditation.
The affidavit states that the BCA Calibration Laboratory holds accreditation through ANAB and suggests that the accreditation process reviews the “breath testing program.”
That description goes too far.
ANAB reviews calibration laboratory procedures and methods. It does not independently audit the entire Minnesota breath-testing program, nor does it certify that the DataMaster DMT source code is free of defects.
Calibration review and source-code review address entirely different issues.
A breath-test machine can satisfy calibration standards while still containing software logic problems affecting:
- sample classification,
- error handling,
- consistency checks,
- or reporting functions.
Those are software questions, not calibration questions.
The BCA’s New Affidavits Ignore What Minnesota Courts Already Learned
Another affidavit asserts that source-code review without concurrent mechanical testing cannot determine whether the instrument functions as intended.
Minnesota courts already know that assertion is incorrect.
Prior source-code litigation in Minnesota and other jurisdictions uncovered software problems that routine calibration checks and operational testing failed to detect. Courts discovered those problems only after experts reviewed the source code itself.
Again, the issue is not whether every breath-testing instrument contains defects.
The issue is whether courts should permit independent verification of software-driven forensic evidence before the State uses a DataMaster DMT breath-test result in a criminal DWI prosecution.
The answer should be yes!
The Minnesota Supreme Court Strengthened DWI Discovery Rights in State v. Manska
Last year, the Minnesota Supreme Court issued an important decision in State v. Manska.
The Court reaffirmed that Minnesota Rule of Criminal Procedure 9.01 imposes a lenient discovery standard. A defendant needs only to show that the requested information “may relate” to guilt or innocence.
That standard matters enormously in DataMaster DMT source-code litigation.
Prosecutors frequently argue that defendants must first identify a known software defect before obtaining source-code discovery. But discovery does not work that way. A defendant ordinarily cannot identify hidden software problems without access to the software itself.
As our recent briefing explains:
If a digital audit trail may relate to reliability under Manska, then the software operating the scientific instrument itself necessarily relates to reliability as well.
Minnesota’s DataMaster DMT Contract Also Matters
The State argues that the DataMaster DMT and its software fall under current agreements with Intoximeters, Inc.
But the instrument and software at issue in our case appear to predate those agreements.
According to the contractual record:
- Minnesota purchased the instrument under a 2010 contract with National Patent Analytical Systems (“NPAS”),
- and the software version at issue was supplied in 2012.
That timing matters.
The original NPAS agreement did not merely create temporary rights that disappeared when the contract expired. The contract expressly granted Minnesota “a perpetual, irrevocable, non-exclusive license” relating to the software and intellectual property associated with the DataMaster DMT.
More importantly, the contract expressly stated:
“The terms and conditions of paragraphs … T … shall survive the cancellation or expiration of this Contract.”
Paragraph T, in turn, contemplated judicial disclosure of source code pursuant to court order and provided:
“Vendor shall provide the requested information in response to a court order…”
That language matters because the State frequently argues that the original NPAS contract expired years ago and that only the newer Intoximeters agreements control access to the DataMaster DMT source code. But contracts routinely contain obligations that survive expiration, especially when the parties expressly say they do.
In other words, DataMaster DMT source-code litigation may not turn solely on the State’s newer Intoximeters contracts.
Minnesota Courts Have Already Ordered DataMaster DMT Source-Code Disclosure
This litigation does not present a new or unprecedented request.
Minnesota courts have already ordered disclosure of DataMaster DMT source code despite similar arguments involving confidentiality, security, and administrative safeguards.
Most notably, then-Judge (now Justice!) Sarah Hennesy ordered disclosure of the DataMaster DMT source code in an implied-consent proceeding. That fact matters because implied-consent proceedings generally impose a higher discovery burden than criminal DWI prosecutions.
Minnesota courts have therefore already recognized an important principle: meaningful adversarial review may require access to the software operating the breath-testing instrument itself.
Why DataMaster DMT Source Code Matters for Minnesota DWI Defense
Modern breath-testing instruments no longer operate as simple mechanical devices.
They function as software-driven forensic systems, making thousands of calculations and decisions during a single testing sequence. The software determines:
- what qualifies as an acceptable breath sample,
- when error conditions trigger,
- how consistency checks operate,
- and how the instrument generates the final reported breath-test result.
The State uses those DataMaster DMT breath-test results in criminal DWI prosecutions carrying serious consequences.
Courts do not permit independent source-code review because they assume forensic instruments are unreliable. Courts permit independent review because scientific reliability depends on transparency, adversarial scrutiny, and verification.
Minnesota courts recognized that principle during the Intoxilyzer litigation.
They should recognize it again now. An experienced Minnesota DWI lawyer can evaluate whether the DataMaster DMT source-code issue may affect your case.
Frequently Asked Questions About DataMaster DMT Source Code in Minnesota DWI Cases
What is DataMaster DMT source code?
The DataMaster DMT source code is the software that controls Minnesota’s breath-testing instrument. It helps determine how the machine collects breath samples, evaluates testing conditions, checks consistency, identifies errors, and reports a final breath-test result.
Why does source code matter in a Minnesota DWI case?
Source code matters because the State often relies on the DataMaster DMT breath-test result as key evidence in a DWI prosecution. If the software contains errors affecting sample classification, error messages, consistency checks, or result reporting, those issues may affect the reliability of the breath-test evidence.
Does a driver have to prove the source code is defective before requesting it?
No. Under Minnesota discovery law, a defendant does not need to prove that the source code is defective before seeking discovery. The Minnesota Supreme Court has reaffirmed that a defendant needs only to show that the requested information “may relate” to guilt or innocence.
Does calibration prove the DataMaster DMT software is reliable?
No. Calibration and source-code review answer different questions. Calibration may show whether an instrument measures a known standard within accepted limits. It does not prove that the software controlling the instrument is free from logic errors, classification problems, or reporting defects.
Have Minnesota courts ordered DataMaster DMT source-code disclosure before?
Yes. Minnesota courts have previously ordered disclosure of DataMaster DMT source code under protective conditions. Those orders recognize that meaningful adversarial review may require access to the software operating the breath-testing instrument.
Can source-code issues affect a Minnesota DWI breath-test result?
Potentially, yes. Source-code issues can affect how a breath-testing instrument processes samples, evaluates safeguards, triggers error messages, and reports results. Whether that matters in a particular case depends on the facts, the instrument, the test record, and the court’s discovery rulings.
Facing a Minnesota DWI Breath-Test Case?
If you are charged with DWI in Minnesota and your case involves a DataMaster DMT breath test, the source-code issue may matter. Breath-test evidence often appears simple on paper, but the software that produces the results can raise complex questions about reliability, discovery, and admissibility.
Ramsay Law Firm has spent years challenging unreliable breath-test evidence and litigating DataMaster DMT source-code issues across Minnesota.
