State Alcohol Lab Refuses to Follow Quality Assurance Guidelines

Posted On October 16, 2023 Charles Ramsay

The state crime lab, the Bureau of Criminal Apprehension (BCA), is at it again, refusing to follow basic quality assurance standards in the blood alcohol lab.

According to the American Academy of Forensics Sciences STD 54, the BCA must include matrix-match blanks with each batch of blood alcohol.

AAFS STD 54 clearly states:

Each lot or batch of blank matrix sample shall be evaluated for the absence of the target analyte(s) or interferences prior to or concurrent with use. The evaluation shall be with the analytical technique employed for that specific method.

EXAMPLE: A negative ELISA screen of a whole blood sample is not sufficient to demonstrate that there are no interferences for a GC/MS method

Blanks ensure the blood/urine alcohol machine can detect the difference between no alcohol and positive alcohol samples. They also ensure that alcohol from a positive sample from one vial doesn’t carry over into the next alcohol-free sample.

But the BCA continues to flaunt quality guidance. Instead of using blanks made up of alcohol-free blood or urine, they use water. They do this because it is easier than using blood or urine.

But using matrix-matched blanks is the only way to tell if your entire process is indeed working correctly.


We’ve taken the BCA to task on a long list of their errors in court. We’ve pointed out that they continually refuse to follow quality recommendations of consensus documents like AAFS STD54.

Here are a few other problems we’ve found in the breath and blood alcohol labs:

When questioned in court, the BCA tries to shirk its duty to maintain high standards for the citizens of Minnesota.

Scientists often state that quality control standards like AAFS 54 are only “recommendations.” But national standards are there for a reason. They ensure that we can have confidence in results.


If the state has charged you with driving over the legal limit for alcohol, you need a law firm that understands the details of the science. At Ramsay Law, we take the science of alcohol testing seriously.

We’re the only law firm in the state with a lawyer board-certified in DWI law (recognized by the ABA, not the MSBA).

Call us to discuss your case. Contact Ramsay Law at 651-604-0000.

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Daniel Koewler