Authored by Caleb Anthony
In one of my recent cases, the State did what it often does in a suspected drug-impaired driving case: it called in a Drug Recognition Evaluator (DRE) and then acted as if that alone should end the discussion.
My client was stopped and eventually accused of driving under the influence of drugs. But the stop itself was not based on bad driving. There was no erratic driving conduct before the stop. Once officers started interacting with him, though, they decided they were looking at impairment, and they called in a Drug Recognition Evaluator.
In Minnesota DWI cases involving drugs, officers often rely on a DRE to support claims of impairment. But when the DRE does not follow the required 12-step evaluation process, the reliability of that opinion becomes a serious legal issue. Courts often treat a DRE’s opinion as reliable evidence, even when the underlying evaluation is incomplete.
What Is a Drug Recognition Evaluator (DRE)?
A Drug Recognition Evaluator (DRE) is trained to conduct a systematic, multi-step investigation designed to determine whether a driver is impaired by drugs. The process is supposed to be thorough, standardized, and focused not just on confirming impairment, but on ruling out other explanations, including medical conditions and lawful prescription use.
The 12-Step DRE Protocol
A proper Drug Recognition Evaluator (DRE) assessment follows a standardized 12-step protocol designed to ensure a thorough and reliable evaluation. That process typically includes:
- Breath alcohol test
- Interview of the arresting officer
- Preliminary examination and first pulse
- Eye examinations (HGN, VGN, lack of convergence)
- Divided attention tests
- Vital signs (pulse, blood pressure, temperature)
- Dark room examinations
- Muscle tone assessment
- Examination for injection sites
- Subject statements and observations
- Opinion of impairment
- Toxicological sample
The DRE only performed two or three of these steps.
The reliability of a DRE’s opinion depends on whether they perform the entire process. This is an issue that comes up regularly in Minnesota DWI cases involving alleged drug impairment.
In my case, the DRE spent about ten minutes talking to my client. That was the “evaluation.” Anyone familiar with how these evaluations are supposed to work knows that is nowhere close to a real DRE. There are 12 steps in the protocol, and this was nowhere close to a full evaluation.
When a DRE Skips the Process
In practice, several recurring problems show up in DRE evaluations, especially in Minnesota DWI cases:
- Incomplete evaluations where only a few of the required steps are performed
- Rushed timelines that do not allow for a meaningful assessment
- Confirmation bias, where the DRE reinforces the arresting officer’s conclusion
- Failure to consider medical conditions that can mimic impairment
- Overreliance on subjective observations instead of objective data
These issues matter because the reliability of a DRE opinion depends entirely on the integrity of the process.
But when the case gets presented later, the State still wants the court to hear the phrase “DRE” and give the opinion all the weight that title is supposed to carry.
If an officer wants the authority that comes with being a DRE, then they should have to do the work that goes with it. The certification is supposed to mean the officer can conduct a full, careful, standardized evaluation. It is not supposed to mean the officer can spend ten minutes with someone, skip most of the process, and then offer an expert opinion dressed up as science.
The DRE did not really investigate. He did not slow down the case. He did not appear to seriously test competing explanations. He came in after the suspicion had already formed and, instead of rigorously working through the full process, essentially reinforced the conclusion the officers already wanted. That is not what a DRE is supposed to be doing.
This is something I am seeing with increasing frequency. More and more, I see what I would call the “not thorough DRE.” The officer arrives, displays their DRE credentials, conducts a less comprehensive evaluation, and then confidently states an opinion as if they had followed the complete protocol.
Why the DRE Process Matters
That matters because the value of DRE testimony is supposed to come from the process. If the process is not actually followed, then the conclusion should not get a free pass just because the officer has specialized training.
In my case, once I dug into the facts, the gap between the DRE’s confidence and the actual evidence became obvious.
The DRE in my case came in with the aura of expertise, but the actual work was thin. The actual science told a different story. That is exactly why courts should be skeptical when they hear the title “DRE” and assume the opinion must be reliable. The question should always be: what did the officer actually do?
Did the officer really perform the full evaluation?
Did the officer seriously rule out other explanations?
Did the officer take the time required by protocol?
Or did the officer just show up long enough to help strengthen an arrest that was already headed in one direction?
Medical Conditions vs. Alleged Drug Impairment
This issue has been on my mind even more because of a recent Minnesota case reported by MPR involving a man whose family alleges police ignored signs that he was suffering a stroke during a traffic stop. What stood out to me in that story was that a DRE responded there as well. That detail matters. When a DRE responds, people should expect them to handle the situation with greater care, discipline, and attention to any potential medical explanation. A DRE is supposed to help officers avoid exactly that kind of mistake, not make it more likely. Cases like this highlight a real risk in Minnesota DWI drug-impaired driving investigations, where medical conditions can be mistaken for drug impairment.
A rushed or incomplete DRE can help turn ordinary medical symptoms, prescription medication effects, anxiety, or neurological problems into evidence of supposed criminal impairment. And once that conclusion gets attached to the case, it can take on a life of its own unless someone forces the State to prove it.
How DRE Testimony Is Used in Minnesota Courts
In Minnesota DWI cases, DRE testimony is often presented as expert opinion to support allegations of drug impairment. Courts may admit that testimony, and juries often give it significant weight. But that weight depends on whether the evaluation was conducted properly. The value of a DRE opinion comes from the process, not the title, and when that process is incomplete, the foundation for the opinion becomes questionable.
Can a DRE Opinion Be Challenged in Minnesota?
Yes. A DRE opinion can and should be challenged when the required protocol is not followed. In Minnesota DWI cases, courts may admit DRE testimony, but its weight depends on whether the evaluation was properly conducted. When key steps are skipped, when alternative explanations are ignored, or when the evaluation is rushed, the reliability of that opinion becomes a central issue in the case.
How We Challenged the DRE
I did not let the State hide behind the acronym. I did not let the DRE label substitute for actual proof. I broke down what the officer actually did, how little of the protocol was actually followed, and how unjustified the confidence in the opinion really was. Then I put the State’s toxicologist on the stand and made sure the case was decided on the real evidence, not a show of expertise.
The Result
The result was the right one. We won the implied consent case, and I later convinced the prosecutor to dismiss the criminal case.
What Courts Should Demand from DRE Testimony
But what stays with me is the larger problem. If officers did the same half-finished evaluations during certification that they sometimes do on the street, I do not believe many of them would ever get certified. Rigorous standards apply during training. In actual cases, the rigor too often disappears, leaving only the conclusion.
If the State wants courts to rely on DRE testimony, then courts should insist on a real DRE. Not a shortcut. Not a ten-minute conversation. Not a few scattered observations. A real evaluation. That is especially true in Minnesota, where DRE testimony can carry significant weight in DWI prosecutions.
If you face a DWI charge involving a Drug Recognition Evaluator, focus on the officer’s actions, not just their claims, and determine if they adhered to the required protocol.
Is it possible to challenge a DRE opinion in Minnesota?
Yes. If the officer does not follow the required 12-step protocol, a good defense lawyer will attack the reliability of the DRE opinion.
What is the DRE 12-step process?
It is a standardized evaluation used to determine drug impairment, including physical tests, observations, and toxicology.
How long should a DRE evaluation take?
A proper DRE evaluation typically takes significantly longer than a brief roadside interaction, often over an hour, because it involves multiple steps and observations.
Is DRE testimony considered scientific evidence?
The State presents DRE testimony as expert opinion, but its reliability depends on whether they followed their standardized protocol. Despite this, the Minnesota Supreme Court has held that DRE testimony is not scientific evidence (State v. Klawitter).
