The hours after a Missouri DWI arrest are some of the most consequential of any criminal case. Decisions made before the suspect even leaves the booking station — whether to take the breath test, what to say to officers, whether to request the administrative hearing — can determine whether the case ends in a dismissal, a reduction, or a permanent record. This guide walks through what every Missouri DWI suspect needs to know in the days after arrest.
The two-track system: criminal case + administrative case
A Missouri DWI arrest triggers two separate proceedings that run on parallel tracks.
The criminal case is what most people think of: prosecutor, judge, court appearances, plea or trial. The criminal charge is "Driving While Intoxicated" under RSMo §577.010. A first offense is a Class B misdemeanor (up to six months in jail and $1,000 fine); subsequent offenses escalate to felony status with mandatory minimum sentences.
The administrative case is run by the Missouri Department of Revenue and decides whether your license gets suspended. The administrative track is independent of the criminal case — you can win the criminal case and still lose your license, or vice versa.
The administrative case has a critical 15-day deadline that most people miss. Failure to request the administrative hearing within 15 days of arrest results in automatic license suspension regardless of what happens in the criminal case.
The 15-day rule: the most important deadline in DWI defense
Missouri's implied-consent law (RSMo §302.505) requires the Department of Revenue to suspend the license of any driver who refused a chemical test or who tested above the legal limit. The driver has fifteen days from the date of arrest to request an administrative hearing to contest the suspension.
If you miss the fifteen-day window, your license is automatically suspended:
• 30 days suspension + 60 days restricted driving if you tested above 0.08% (over 0.04% for commercial drivers, 0.02% for under-21).
• One year revocation if you refused the chemical test.
The administrative hearing itself can be won on procedural grounds — defects in the stop, problems with the chemical test, errors in the arresting officer's paperwork, lack of probable cause for the arrest. Even when the criminal case proceeds, winning the administrative hearing keeps your license intact.
What you should and shouldn't say after a DWI stop
The decisions you make at the roadside affect the entire case.
Identify yourself and provide license, registration, and insurance. Required.
Decline to answer questions about drinking. "I'd prefer not to answer that, officer." You are not required to discuss whether you've been drinking, when, where, or how much.
Decline field sobriety tests. Field sobriety tests — walk-and-turn, one-leg stand, horizontal gaze nystagmus — are largely voluntary in Missouri and are routinely failed even by sober people. There is no penalty for declining.
Decide whether to take the breath test. This is the hardest decision and there is no universally right answer. Refusing produces an automatic one-year license revocation. Taking the test and blowing over 0.08% provides the prosecutor's strongest evidence in the criminal case but produces a much shorter administrative suspension. Many defense attorneys recommend taking the test for first-offense suspects with no prior record.
Do not perform a portable breath test (PBT) at the roadside. Different from the official chemical test at the station. The PBT is generally not admissible at trial in Missouri, but officers use it to establish probable cause for arrest. Decline.
Do not consent to vehicle searches. If officers want to search your car, they must have probable cause. "I do not consent to a search" is the right answer.
Request a lawyer at the station. Once at the station, ask for a lawyer before any questioning. Even one phone call to counsel before deciding whether to take the chemical test can change the outcome of the case.
Common DWI defenses
Missouri DWI cases produce more pretrial motions and more defense angles than nearly any other criminal charge category. Common defenses:
Defects in the stop. The officer must have reasonable suspicion of a traffic violation or impairment to pull you over. Pretextual stops, stops based on innocent driving behaviors, or stops without articulable cause can produce suppression of all subsequent evidence.
Defects in the arrest. Probable cause for the DWI arrest must come from observed driving, observation at the stop, and (sometimes) field sobriety performance. Weak probable cause is grounds to suppress.
Breathalyzer maintenance and calibration. Missouri requires specific breathalyzer maintenance schedules. Maintenance records, calibration certificates, and operator certifications are all subpoenable. Defects can suppress the breath result.
Chain of custody on blood draws. Blood-draw cases require strict chain-of-custody documentation. Breaks in the chain produce suppression.
Medical and physiological defenses. Diabetes, GERD, ketosis, and recent dental work can all produce false-high breath readings. Documented medical conditions are powerful defense evidence.
Rising-blood-alcohol defense. The breath test occurs at the station, sometimes 30–60 minutes after the stop. If your BAC was below 0.08% at the time of driving but rose above by test time, the test result doesn't prove driving while intoxicated.
Penalties and license consequences
Missouri DWI penalties escalate with prior offenses:
• First offense: Class B misdemeanor, up to 6 months jail, up to $1,000 fine, 30-day license suspension, 60-day restricted privilege.
• Second offense (within five years): Class A misdemeanor, mandatory 10 days jail, 1-year license revocation, ignition interlock required.
• Third offense: Class E felony (Persistent Offender), mandatory 30 days jail, 10-year license denial.
• Fourth offense or DWI causing serious injury or death: Class D or higher felony, multi-year mandatory minimums.
The license consequences continue beyond the criminal sentence. Missouri's Abuse-and-Lose statute (RSMo §577.500) and the points system extend the practical impact of even a first conviction.
Why the call costs you nothing
Most DWI cases at our firm are handled on a flat-fee basis, quoted in writing before any work begins. The first consultation is free. There is no charge if we evaluate your case and decline to take it.
The most expensive mistake in Missouri DWI defense is delay. The fifteen-day administrative hearing deadline runs from the date of arrest, not the date charges are filed. Discovery deadlines run quickly. Surveillance video at the stop or station gets overwritten. Calling within days of arrest meaningfully improves outcomes.
The bottom line
A Missouri DWI arrest triggers two separate cases — criminal and administrative. The fifteen-day administrative deadline is the most-missed and most-consequential timing rule. Decline field sobriety tests, decline vehicle searches, decline to discuss drinking, and request counsel at the station. The defenses are real — defects in the stop, problems with the breathalyzer, chain-of-custody breaks, medical conditions — but they require timely investigation. Call before the criminal arraignment if you possibly can.
Frequently asked questions
How long do I have to act on a Missouri DWI license suspension?
Fifteen days from the date of arrest to request an administrative hearing with the Missouri Department of Revenue under RSMo §302.505. Miss this window and your license is automatically suspended (30 days for over-the-limit cases, one year for chemical-test refusals) regardless of how the criminal case plays out.
Should I take the breath test after a DWI stop in Missouri?
There's no universally right answer. Refusing produces an automatic one-year license revocation. Taking the test and blowing over 0.08% provides the prosecutor's strongest evidence but produces a shorter suspension. Many defense attorneys recommend taking the test for first-offense suspects with no prior record. Some recommend refusing for repeat offenders. Get counsel involved if at all possible before deciding.
Can a Missouri DWI be reduced or dismissed?
Frequently, depending on the facts. Issues with the stop, the field sobriety procedures, the breathalyzer maintenance records, or the chain of custody on a blood draw can all create grounds for suppression or reduction. The earlier the defense investigation begins, the more options remain available.
What's the difference between DWI and DUI in Missouri?
Missouri uses 'DWI' (Driving While Intoxicated) as the primary statutory term. Some states use 'DUI' (Driving Under the Influence). For practical purposes they refer to the same offense — operating a motor vehicle while impaired by alcohol or drugs.
Will a Missouri DWI stay on my record forever?
DWI convictions on the Missouri driving record are permanent (the points portion clears in three years, but the conviction remains). On the criminal record, RSMo §577.054 allows expungement of a first-offense alcohol-related driving conviction after ten years if you've remained conviction-free. Repeat offenses generally cannot be expunged.
Do I need a lawyer for a first-time Missouri DWI?
Yes — even for a first offense. The administrative hearing alone is technical enough that pro-se applicants rarely succeed. The criminal case carries a permanent record, employment consequences, insurance impacts, and immigration consequences (for non-citizens). The cost of a flat-fee DWI defense is far less than the lifetime cost of a conviction.
This article is general legal information for Missouri residents. It is not legal advice. Missouri law changes regularly — statutes are amended, case law evolves, and the application of any rule depends on the specific facts of each case. Do not act, or refrain from acting, based on this article without consulting a qualified Missouri attorney about your particular situation. Reading this article does not create an attorney-client relationship. For advice on your specific case, contact David Naumann & Associates at (314) 831-9350. The initial consultation is free. See the full Legal Disclaimer for complete terms.