California prohibits operating a vessel while under the influence, a charge usually called BUI. It is governed by Harbors and Navigation Code 655, not the Vehicle Code, but it works much like a DUI and is taken just as seriously on the water. I am Joel Brand, and here is how a BUI works and how I defend one.
What the law prohibits
Section 655 makes it unlawful to operate any vessel, water skis, an aquaplane, or a similar device while under the influence of alcohol or drugs, and it sets a 0.08 percent limit for recreational vessels operated by adults. Operators of commercial vessels and certain others face lower limits. The law reaches motorboats, sailboats under power, jet skis and other personal watercraft, and more. Just as on the road, the prosecution can proceed either on the impairment theory or on the per se limit, so a BUI mirrors the two-pronged structure of a Vehicle Code DUI.
What it carries
A first BUI is typically a misdemeanor with fines, possible jail, and a court-ordered boating safety or alcohol program. When a BUI causes injury, the exposure rises sharply, much like a DUI causing injury, and it can be charged as a felony with significant custody time depending on the harm. Unlike a DUI, a standard BUI does not by itself suspend your driver's license, though related conduct can. The penalties are serious enough that a BUI should never be treated as a minor boating ticket.
A BUI is not a driver's-license DUI
One important distinction is that a BUI runs through the criminal court but does not trigger the DMV administrative license process the way a vehicle DUI does. There is no automatic license suspension and no separate DMV hearing on the boating offense itself. That said, a BUI is still a criminal alcohol-related conviction that can show up on background checks and can matter if you later face a vehicle DUI, so the absence of a license suspension does not make it harmless.
Why erratic operation proves less on the water
BUI cases have their own weaknesses, starting with the operation itself. There are no lane lines on the water, so the usual driving cues that officers rely on simply do not apply. Wind, current, wakes from other boats, and choppy conditions explain a great deal of what an officer might call erratic operation. A boat that drifts, swings wide, or rocks is doing what boats do in moving water, and that ordinary behavior is a far weaker indicator of impairment than weaving across a marked highway lane.
Field sobriety tests fail on a boat
The standardized field sobriety tests were designed and validated for solid, level ground, and they fall apart on the water. A rocking deck, the lingering loss of balance that comes from hours on a boat, wet surfaces, and confined space make tests like the walk-and-turn and one-leg stand nearly meaningless. Many officers move the tests to the dock or shore, but even then the effects of sun, dehydration, and a day on the water can mimic impairment. These reliability problems give a defense real leverage over the field-test evidence. See field sobriety tests.
The stop and the testing
The chemical testing rules still have to be followed on the water just as on the road, including proper procedures for breath or blood collection and a valid chain of custody. The lawfulness of the stop is also a live issue. Marine patrol officers and game wardens have authority to conduct certain safety and equipment inspections, but using a routine inspection as a pretext to launch a full impairment investigation raises questions a defense can press. I examine the basis for the contact closely, because what is justified as a safety check is not automatically a license to investigate for alcohol.
How I defend a BUI
A BUI is defended on the operation, the testing, and the stop, just like a DUI, but with the water-specific facts working in the client's favor. I challenge the inference that ordinary boat handling shows impairment, attack the field testing as unreliable in a marine setting, scrutinize the chemical evidence and chain of custody, and test whether the contact and any detention were lawful. The recreational, social context of most boating cases also supports favorable resolutions where the evidence is thin. See also my top DUI defenses.
Conditions that mimic impairment on the water
A day on the water produces effects that look a lot like intoxication but are not. Prolonged sun exposure, dehydration, the constant motion of the boat, engine noise, glare off the water, and wind all leave a person flushed, unsteady, red-eyed, and slow to respond by the time an officer makes contact. This phenomenon is well recognized among boaters, and it can easily be mistaken for, or layered on top of, the effects of a drink or two. I make sure these innocent explanations are on the table, because an officer who attributes every sign to alcohol is ignoring the ordinary toll that boating itself takes on the body.
How a BUI can affect a future DUI
Although a BUI does not suspend your driver's license, it is still an alcohol-related conviction that can echo later. Depending on the circumstances and timing, a prior BUI can be treated as relevant if you later face a vehicle DUI, and it certainly appears on a criminal background check. That long tail is one more reason to take a BUI seriously and fight it rather than accepting a quick plea, since the conviction can reach beyond the immediate penalties into how a later case is charged and how employers and licensing boards view your record.
Charged with a BUI?
Every BUI turns on the operation, the conditions, and the testing, which is exactly what I review with you. Use the free case analysis on this page, or call me directly at (888) 271-6644. I answer my own phone, 24/7.
From the DUI blog: 9 surprising ways you can get a DUI in California.