Derek Alexander Knapp v. Commissioner of Public Safety
a241440
Minn. Ct. App.May 19, 2025Background
- Respondent Derek Knapp’s driver's license was revoked following a DWI arrest in Minnesota in February 2023, after a breath alcohol concentration of 0.08 was detected using a DataMaster DMT-G (DMT) device.
- Knapp challenged his license revocation, arguing that the breath test results were inadmissible due to an inadequate pretest observation period.
- At the implied-consent hearing, the commissioner introduced evidence that a certified DMT operator administered the test and the device passed all diagnostic checks.
- The district court found the observation period was insufficient—due to limited officer observation—and rescinded the revocation based on concerns about reliability of the test results.
- The Commissioner of Public Safety appealed, arguing it had met the burden required for admissibility under established precedent, and no evidence was presented that any event (e.g., ingestion, regurgitation) invalidated the results.
Issues
| Issue | Plaintiff (Knapp) Argument | Defendant (Commissioner) Argument | Held |
|---|---|---|---|
| Whether the DMT test results were admissible | Improper observation undermined reliability; insufficient to admit | Prima facie case made by certified operator and diagnostics | Commissioner satisfied burden; results admissible |
| Whether reliability concerns required exclusion | Lax observation period itself is enough to render results unreliable | Any flaw in observation affects weight, not admissibility | Observation flaws don't void results without more evidence |
| Burden to show actual compromise of results | Plaintiff did not have to show specific ingestion or regurgitation | Burden shifts to plaintiff to show an event impacted results | Plaintiff offered no such evidence; revocation reinstated |
| Application of precedent regarding observation period | Complete observation period required for scientific reliability | Only test operator certification and diagnostics required | District court misapplied law; relied too heavily on observation period |
Key Cases Cited
- Vondrachek v. Comm’r of Pub. Safety, 906 N.W.2d 262 (Minn. App. 2017) (establishes prima facie standard for admissibility of DMT breath test: certified operator and passing diagnostics suffice)
- Kramer v. Comm’r of Pub. Safety, 706 N.W.2d 231 (Minn. App. 2005) (admissibility burden met by showing machine in working order and certified operator)
- Melin v. Comm’r of Pub. Safety, 384 N.W.2d 474 (Minn. App. 1986) (deficiency in observation period alone doesn’t invalidate test)
- Falaas v. Comm’r of Pub. Safety, 388 N.W.2d 40 (Minn. App. 1986) (drivers must provide more than speculation to challenge breath test results)
- State v. Wickern, 411 N.W.2d 597 (Minn. App. 1987) (observation period flaws only go to weight, not admissibility, of breath test results)