Another Victory for Source Code!!

Posted On October 30, 2023 Charles Ramsay

We racked up another source code victory! Two weeks ago, a judge out of Rock County granted us access to the state’s breath alcohol machine’s source code!! 

More judges are starting to see through the state’s source code charade. We’re not asking for the keys to Fort Knox; we’re simply asking to see the software code behind the machine that’s accusing our client of being guilty. 

Everything about the state’s breath alcohol machine, the DataMaster DMT (DMT), is controlled by software. And we want to examine the software to make sure it’s analyzing our client's breath properly. 

When someone blows into a breath alcohol machine, there are complicated calculations that take place. And we’ve found some discrepancies between what the state says is happening and what is actually happening in the code. 

In 2017, we found that breath samples were being accepted at lower flow rates than what the state told us. After gathering extensive discovery, we saw samples being accepted at flow rates of under 3 liters per minute. 

The state was embarrassed. They didn’t even know what the minimum flow rate was.

We need the make sure that the machine is doing what the state tells us it is doing. We want to verify critical functions like:

  • Minimum volume acceptance criteria
  • Interfering substances calculations - when does it flag?
  • Water vapor compensation
  • Barometric pressure compensation
  • Does it actually take the lowest number, or does it take an average?
  • Control tolerance check - is it using 3 or 4 digits to check the control tolerance?


The court agreed with us. It found that the state actually does have control over the source code, and they need to let us see it.

We dug into the original contract between MN and the breath test manufacturer, National Patent Analytical Systems (NPAS). We showed the judge that the original contract includes access to the source code. It requires compliance with any court order to disclose the code. Even beyond the contract term, those duties survive. 

The court concluded that the state has possession and control over the code, and we have a right to view it.


The state needs to stop fighting this dreary battle. We’ve been through this before. During the last source code battle, we found problems with the source code. Problems that required fixing.

The machine was accusing citizens who blew too hard into the instrument of not having blown at all!

Instead of trying to hide problems, the state should be eager to fix them.


If you’ve been a victim of the state’s guilty box, call Ramsay Law. We’re the only law firm in the state with a lawyer board-certified in DWI law (recognized by the ABA, not the MSBA).

We leave no stone unturned when looking at your case.

Call us at 651-604-0000.

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