You are pulled over, the roadside tests go badly, and the breath machine reads 0.00%. You figure, “That settles that.” When suddenly, an officer you have never met takes your pulse three times, studies your pupils in a darkened room, checks your arms for needle marks, and decides drugs impair you.
Jurors can find that kind of methodical, step-by-step conclusion persuasive, but what they rarely hear, unless someone shows them, is how many of those steps come down to a judgment call. That is why it is critical to seek and take legal advice from a DWI defense lawyer.
Yes. A Drug Recognition Expert can be wrong. A DRE evaluation follows a standardized protocol, but the officer’s ultimate conclusion still depends in part on observations, interpretation, test administration, statements, medical information, and other evidence. In New Mexico, the State must ultimately prove that a drug affected the person to the degree that the person was incapable of safely driving. Not merely that the substance is present in the blood.
NMSA § 66-8-102
In This Article
Marc Grano explains what a DRE is, how the 12-step evaluation works, where errors or assumptions can enter the process, and how the defense can test the DRE’s conclusions in court. Grano Law Offices, P.C. wrote this post to provide general legal information to those arrested for a drug-related DWI about their options.
Table of Contents
What Is a Drug Recognition Expert (DRE)?
A Drug Recognition Expert (DRE) is a police officer certified through the Drug Evaluation and Classification (DEC) Program. The Los Angeles Police Department developed it in the early 1970s. Today, it is managed by the International Association of Chiefs of Police (IACP) with support from the National Highway Traffic Safety Administration (NHTSA).
Their job is to decide whether a driver is impaired by something other than alcohol and, if so, what kind of drug is responsible using a 12-step DRE protocol.
A DRE is rarely the officer who makes the stop. If the breath result does not account for the suspected impairment, that officer can request the presence of a DRE. In practice, that can mean a wait at the roadside or station while an evaluator is found, which pushes the eventual blood draw further from the time of driving.
How the 12-Step DRE Protocol Works
The 12-step DRE protocol seeks to determine drug impairment in a standardized manner for every DWI suspect. The steps follow a fixed order, including:
- Submit to a breath alcohol test
- Interview the responding officer
- Launch a preliminary examination and check first pulse
- Perform an eye examination
- Carry out divided attention psychophysical tests
- Take vital signs and second pulse
- Administer a dark room examination
- Conduct a muscle tone test
- Look for injection sites on your body and take the third pulse
- Make a note of your statements and other observations
- Provide a DRE analysis and opinion
- Finalize the toxicological examination
When the evaluation ends, the DRE writes up the findings, names the suspected drug category or categories, and sends the sample off for testing. In New Mexico, DWI blood samples are analyzed by the Department of Health’s Scientific Laboratory Division. Prosecutors then present the DRE’s opinion alongside the lab report, hoping jurors see the two as confirming each other’s findings.
Flaws in the 12-Step DRE Evaluation: Why Observation Is Not Proof
New Mexico courts permit properly founded DRE testimony. But admissible evidence is not necessarily accurate evidence, and a DRE’s conclusion remains subject to cross-examination like any other expert opinion. The problem is that the protocols depend on human judgment made under imperfect conditions. Small errors, assumptions, or misinterpretations can accumulate through the evaluation and ultimately affect the reliability of the officer’s final opinion.
Here is where things can go wrong with the 12-step DRE protocol listed above:
- Flaws in Steps 1 and 2. A low breath result is what triggers the call, so the DRE walks in already knowing the arresting officer suspects drugs. The DRE then hears the officer’s account of your alleged behavior before they even start examining you. That sequence creates a potential confirmation-bias issue: before conducting the evaluation, the DRE already knows that another officer suspects drug impairment. A careful defense therefore compares the DRE’s observations against the actual video, reports, medical history, toxicology, and other objective evidence.
- Flaws in Step 3. The preliminary exam is partly meant to catch injuries or conditions that have nothing to do with drugs. However, diabetes, concussions, inner-ear problems, neurological disorders, and exhaustion can all mimic impairment, which a DRE cannot define.
- Flaws in Steps 4 and 5. Eye examinations and divided-attention tests can provide useful information, but the meaning of an observed “clue” is not self-proving. The defense should examine whether each test was properly administered, whether the officer accurately recorded what occurred, whether medical or physical conditions affected performance, and whether the observations actually support the drug category identified by the DRE. T
- Flaws in Steps 6 through 9. Pulse and blood pressure climb with fear, and being arrested is frightening. Pupil size is estimated with a measuring device called a pupilometer, muscle tone is assessed by feel, and a mark on the arm might be from a recent blood donation or IV, not from drug use.
- Flaws in Steps 10 through 12. A remark like “I smoked marijuana last weekend” can end up treated as evidence of marijuana DUI impairment. The opinion is formed before toxicology comes back, and toxicology shows that a substance was present, not that it impaired you.
These counterarguments matter because of the requirements New Mexico courts impose on prosecutors to obtain a conviction. Under NMSA § 66-8-102(B), the State must prove you were under the influence of a drug to a degree that made you incapable of safely driving. Unlike the 0.08 alcohol limit, the statute sets no per se drug level, so a positive blood test alone does not meet that standard.
That distinction matters. A laboratory can identify a substance in a blood sample. But under New Mexico law, the ultimate question is whether the State can prove that the drug affected the driver to the degree that the person was incapable of safely driving. Those are not necessarily the same question.
It is critical to hire a DWI defense attorney to help you investigate, determine, and challenge the charges against you.
Follow These Six Steps to Protect Your Legal Rights
Your actions after a drug DWI arrest can affect the outcome of your case. It is critical to understand that evidence degrades, and memories fade, and even missing a single deadline can negatively impact your case.
Follow the six steps below to protect your legal rights generally and the future of your case:
- Do not make self-incriminating statements. Remain polite and ask for a lawyer before answering any questions regarding substances, medications, or timing.
- Write down your timeline now. Note how much you slept, what you ate, every medication you take, any medical conditions, and when you last used anything.
- Gather prescriptions and medical records that could explain your vital signs, eye findings, or balance.
- Check your paperwork for a notice of revocation. If you were served with one, NMSA § 66-8-112 gives you only 10 days to request an MVD hearing that protects your right to drive.
- Keep the arrest off social media, including texts or posts that joke about it.
- Contact a Drug DUI Attorney such as Marc Grano of Grano Law Offices, P.C.
None of these steps are complicated, but each one preserves something your defense may need later. The MVD deadline deserves special attention because it runs on its own clock, separate from the criminal case. A short conversation with an attorney early on helps make sure nothing slips through the cracks.
Our Drug DWI Lawyer Will Defend Your Charges
Marc A. Grano has worked these cases from both sides, first as a New Mexico state prosecutor and U.S. Army JAG officer, and now as a defense attorney with more than 25 years in New Mexico courts. He has completed NHTSA’s ARIDE course, the NHTSA/IACP Standardized Field Sobriety Testing Instructor Development Course, the National College for DUI Defense’s Serious Science course in blood drug analysis, and serves as NCDD’s New Mexico State Delegate.
He knows the protocol your DRE was supposed to follow, and where they tend to get it wrong.
Get Your Free Case Strategy Session with Marc
Do you want a straight read on what the State has to prove, what can be challenged, and what a realistic path forward looks like? Consider scheduling a Free Case Strategy Session with our drug DWI defense attorney at Grano Law Offices, P.C. by calling (505) 426-8711 or messaging us below. We’re available 24/7/365 by phone or video.
