Updated July 2026 · 8 min read
Operating with a PAC in Wisconsin means driving with a Prohibited Alcohol Concentration — the per-se, number-based charge under Wis. Stat. § 346.63(1)(b) (0.08 for most drivers, 0.02 for a 4th-or-subsequent offense or while under an interlock order). It is a separate legal theory from OWI, § 346.63(1)(a), which is about impairment. Prosecutors file both from one stop, but § 346.63(1)(c) lets you be convicted of only one. Mays Law Office defends OWI and PAC cases across Madison, Middleton, and Wisconsin.
If you were arrested for drunk driving in Dane County, you probably left the scene holding two citations for what felt like one event: an OWI and a PAC. That is not a mistake, and you were not charged twice by accident. Wisconsin law deliberately splits an impaired-driving arrest into two separate charges — and then, just as deliberately, allows the court to convict you of only one. Understanding how those two charges fit together is the starting point for any real defense. At Mays Law Office, we walk clients through exactly what each charge means, drawing on what the Wisconsin Statutes actually say rather than the out-of-state guides that get this wrong.
What “Operating With a PAC” Actually Means (and How It Differs From OWI)
“PAC” stands for Prohibited Alcohol Concentration, and it is codified at Wis. Stat. § 346.63(1)(b). It makes it illegal to operate a motor vehicle when “the person has a prohibited alcohol concentration.” This is the per se charge — the “per se” is Latin for “by itself,” meaning the number alone establishes the violation. If your chemical test comes back at or above the legal threshold and the test is believed, the PAC is essentially proven, whether or not you looked or drove impaired.
OWI — Operating While Intoxicated, at Wis. Stat. § 346.63(1)(a) — is a different animal. It targets driving “under the influence of an intoxicant… to a degree which renders him or her incapable of safely driving.” No specific number is required. An OWI can be proven on the officer’s observations alone — erratic driving, the odor of alcohol, slurred speech, or performance on field sobriety tests. In short:
- OWI (§ 346.63(1)(a)) is about impairment — how you drove and how you appeared.
- PAC (§ 346.63(1)(b)) is about the number — what the breath or blood test measured.
One quick note on vocabulary: many people call this a “DUI” or “DWI.” In Wisconsin, the statutory offense is OWI. “DUI,” “DWI,” and “drunk driving” are everyday terms with no separate legal status here — they all fall under § 346.63.
The PAC Thresholds Are Not the Same for Everyone
The concentration that counts as “prohibited” depends on your driving history and license class:
- 0.08 for a driver with two or fewer prior countable offenses — the standard limit.
- 0.02 for a driver with three or more prior offenses, or anyone currently subject to an ignition interlock device (IID) order.
- 0.04 for commercial drivers operating a commercial motor vehicle (§ 346.63(5)).
- Above 0.0 — “Absolute Sobriety” — for drivers under 21.
Wisconsin also has a related, zero-tolerance charge for a Restricted Controlled Substance (§ 346.63(1)(am)), which applies to any detectable amount of a substance like active THC, cocaine, or methamphetamine in the blood, regardless of actual impairment.
Why Prosecutors File Both Charges From One Stop
Charging both OWI and PAC is not overreach — it is evidentiary insurance. In any impaired-driving case, the state carries the burden of proof, and any single piece of evidence can be challenged or suppressed. By filing both charges, the prosecutor builds two independent paths to the same result, so the case does not collapse if one path fails.
That works because the two charges rest on completely different evidence:
- OWI is impairment-based. It relies on the officer’s subjective observations — driving pattern, appearance, statements, and field sobriety testing. It can be proven with no chemical test at all.
- PAC is number-based. It relies solely on whether the chemical test result met or exceeded the threshold. It is mathematical and objective.
The chemical evidence itself comes from Wisconsin’s implied-consent law, Wis. Stat. § 343.305. By driving on a Wisconsin highway, you are “deemed to have given consent” to a breath, blood, or urine test on a lawful request. (Refusing that test is a separate violation with its own license consequences — and a refusal does not, by itself, prevent an OWI conviction.)
Here is the practical payoff of dual charging: if a judge later suppresses a flawed blood test — destroying the PAC case — the prosecutor can still pursue a conviction on the OWI using the officer’s testimony. File one charge, and a single successful challenge can end the case. File both, and the state hedges its bet.
Do I Have to Pay Both Tickets?
This is one of the most common worries we hear, and the answer brings relief: no. You received two citations, each listing a fine, but you are not financially liable for both. Because Wisconsin law permits only a single conviction from one incident (more on that below), any guilty findings from the same stop merge into one conviction — you pay the fine and surcharges tied to that single conviction the court enters, not to both citations.
Which Charge Is Easier to Fight: Attacking the Test vs. Attacking the Observations
Because OWI and PAC rest on different evidence, they are defended in different ways. There is no universal “easier” charge — it depends entirely on where the weakness in your case lies. A defense attorney looks hard at both sides.
Fighting the PAC (attacking the number). A PAC case lives or dies on the chemical test, so the defense focuses on the science:
- The calibration, maintenance, and margin of error of the breath-testing instrument.
- The chain of custody and handling of a blood sample.
- The legality of the blood draw itself and whether a warrant was required.
- Whether the sample was taken within the statutory window that gives it a presumption of validity.
Fighting the OWI (attacking the observations). An OWI case rests on the officer’s subjective read of the situation, so the defense probes that judgment:
- Alternative explanations for poor balance on field sobriety tests — injury, medical conditions, footwear, or road conditions.
- Whether fatigue, nerves, or something other than alcohol explained the driving.
- The reliability and completeness of the officer’s observations.
This is process work, not a promise. We cannot tell you a charge will be “beaten” or “dismissed” — no honest lawyer can. What we can do is examine whether the traffic stop, the field testing, and the chemical testing were lawful and reliable, and build your defense from there. Sometimes the numbers are vulnerable; sometimes the observations are. Knowing which is where an experienced OWI defense begins.
Why You Can Be Charged With Both but Convicted of Only One
Wisconsin anticipated the obvious fairness problem with charging one person twice for the same drive. The answer is written directly into the statute. Wis. Stat. § 346.63(1)(c) provides that a prosecutor may proceed on any combination of the OWI, PAC, and related charges “for acts arising out of the same incident or occurrence” — but if the person is found guilty of any combination of them, “there shall be a single conviction for purposes of sentencing.”
In plain terms: even if a jury believes both the officer’s testimony about impairment and the breath-test number, those guilty findings merge, and the court enters a judgment of conviction on only one charge. You pay one fine, serve one revocation, and carry one mark on your driving record. The charges are alternative theories of a single offense, not two offenses.
That single mark still matters, though. Under Wis. Stat. § 343.307, the state counts prior convictions, suspensions, and revocations to set the penalty tier for any future offense. And Wisconsin’s look-back rules are strict:
- A prior counts toward a second offense only if it happened within a 10-year window. If your first offense is 11 years old, a new charge is again treated as a first offense.
- From the third offense onward, the look-back is lifetime — every prior OWI you have ever had counts, even one from decades ago. That is how Wisconsin reaches its felony tiers.
So while a single conviction is the rule from any one arrest, that conviction becomes a permanent building block for whatever comes next.
First-Offense Realities in 2026: The Civil Forfeiture, the $535 Surcharge, and the Interlock Thresholds
Wisconsin is unusual in treating a standard first-offense OWI or PAC as a civil forfeiture — a non-criminal traffic matter — rather than a crime, as long as no aggravating factor is present (such as a passenger under 16 in the vehicle or an injury). Under Wis. Stat. § 346.65, that means a standard first offense carries no jail time, no right to a court-appointed public defender, and no criminal record. It is not “nothing,” but it is not a crime.
The costs, however, are real. For a 2026 standard first offense, expect:
- The civil forfeiture (base fine): “not less than $150 nor more than $300,” under § 346.65(2)(am)1.
- The Driver Improvement Surcharge: $535, imposed under Wis. Stat. § 346.655. This surcharge — larger than the base fine itself — is mandatory, and the court cannot waive it. (You may still see outdated guides quote the old $435 or $365 figure; the current, statute-set amount is $535.)
- The Safe-Ride-Program surcharge: an additional $75, applied on conviction alongside the driver-improvement surcharge.
- License revocation: a standard first-offense conviction triggers a revocation of roughly 6 to 9 months.
- AODA assessment: every OWI, including a first offense, requires a court-ordered Alcohol and Other Drug Abuse (AODA) assessment and driver-safety plan.
- Reinstatement fee: the DMV charges a reinstatement fee before standard driving privileges return.
When a First Offense Requires an Ignition Interlock
Not every first offense means an ignition interlock device (IID). Under Wis. Stat. § 343.301, an IID is mandatory on a first offense only if:
- Your alcohol concentration was 0.15 or higher at the time of the offense, or
- You improperly refused the implied-consent chemical test.
When an IID is ordered, the minimum restriction period is one year, it must be installed on each vehicle you own or operate, and you bear the installation and maintenance costs. For every second-or-subsequent offense, and for every chemical-test refusal, the IID is mandatory regardless of BAC.
An important 2026 note: the driving thresholds themselves are dropped once you are under an IID order or reach a fourth offense — the PAC limit falls from 0.08 to 0.02. A first offense may be civil, but it changes the rules that apply to you afterward.
Charged With an OWI or PAC in Dane County? Talk to Mays Law Office.
Getting two citations from one stop is frightening, and the online answers about what happens next are frequently wrong. The reassuring part is this: because OWI and PAC are alternative theories of one offense, the state’s case has two moving parts — and a careful defense examines both. Attorney Stephen E. Mays, a former Dane County prosecutor and a member of the National College for DUI Defense, brings that inside perspective to every OWI and PAC case the firm handles across Madison, Middleton, and Wisconsin.
If you are facing an OWI or PAC charge, we offer a free, confidential consultation to talk through the stop, the testing, and your options — no pressure and no guarantees, just an honest look at where your case stands. Learn more about how we defend these cases on our OWI / DUI defense page, and when you are ready, contact us and tell us how we can reach you.
This article provides general legal information and is not legal advice. Reading it does not create an attorney-client relationship. Laws change and every case turns on its specific facts. Consult a licensed Wisconsin attorney about your situation.